Thursday, 29 November 2012

Volumetric Efficiency 101

Volumetric Efficiency 101
by Brian Barnhill

Source :

This can actually be a quite tricky subject, mostly due to confusion and differing opinions among many people. Volumetric efficiency (VE) is typically defined as "the actual amount of air being pumped by the engine as compared to its theoretical maximum."
Basically, VE is a measure of how "full" the cylinders are.

As most of us will know from basic science, gas will expand to fill its container. Seemingly, that would suggest that the cylinder is always full. And, in the pure volumetric sense, that is correct. A 0.5 Liter cylinder will always have 0.5 liters of air in it. The measure we are looking for here is air density. A cylinder with 500 mols/liter of air in it is said to me "more full" than one with 400 mols/liter.
Now, where is this air density measured?

This is one of the points of disagreement. The point at which air density is measured is crucial. Many will claim that you must take the measurement at a standard, such atmospheric density. This, however, can cause many issues with VE measurements. Forced induction cars will have skewed VE values due to the simple fact that they are forcing more air into the manifold. With more air available to the engine, it will receive a larger/more dense amount. This is not a pure measurement of the efficiency of the engine,

To correct for these factors, air density available at the intake manifold should be used. This will correctly measure the VE based on the amount of air available to the engine. As a simple example: Take a 4 cylinder, 2.0 Liter engine (assume even flow to each cylinder) each cylinder will be 0.5 liters. If the intake manifold has a density of 100 mols/liter (this gives 25 mols/cyl), at 100% VE, the cylinder will have 25 mols/Liter. This comes from the equation:
VE = Densitycylinder/Densitymanifold * 100%

Lets look at this another way. Say the cylinder in a single cylinder engine has 186 mols/Liter. Now, the density of at the manifold is measured at 213 mols/Liter. The calculation of VE gives: VE = 286/213 * 100% or 87.32%
It is upon this principle that variable valve timing and similar technologies rely.

They will change the flow aspects of the engine to best match the particular RPM range. An engine is typically only maximized for a particular rpm range. By allowing the change in parameters, this can be overcome. This can easily be seen when looking at DYNO charts for any Vtec equipped engine (the S2000 is a good example). In these charts there will be a "double peak." The horsepower will begin to fall off at one point, and then climb again. This rpm point will correspond to the "Vtec" point.

Volumetric Efficiency plays a large role in how your engine operates. By understanding this parameter one can begin to grasp the details required to properly tune any engine.

4G63 Camshaft Specifications

CAM ADV Duration Duration @ 1mm Peak Lift (mm) Centerline
Intake OEM EVO 248 200 9.8
Exhaust OEM EVO 248 200 9.32
lIntake Brian Crower 272 206 10.54
Exhaust Brian Crower 272 206 9.86
Intake Brian Crower 276 216 11.07
Exhaust Brian Crower 276 216 11.07
Intake Brian Crower 280 213 10.3
Exhaust Brian Crower 280 216 10.36
Intake Brian Crower 288 222 11.83
Exhaust Brian Crower 288 220 12.14
Intake Buddy Club Spec 1 264 10.8 108
lExhaust Buddy Club Spec 1 272 10.2 107
Intake Buddy Club Spec 2 272 10.8 108
Exhaust Buddy Club Spec 2 264 10.2 107
Intake Eitidd‘. Club Spec 3 280 10.3 116
Exhaust Buddy Club Spec 3 230 10.2 116
Intake Buddy Club Spec 4 290 11.5 110
Exhaust Buddy Club Spec 4 290 11.5 110
Intake Comp 264 248 10.3 104
Exhaust Comp 264 248 10.2 112
Intake Comp 272 256 10.8 104
Exhaust Comp 272 257 10.2 112
Intake Comp 280 264 11 104
Exhaust Comp 280 265 10.4 112
Intake Cosworth M2 272 11
Exhaust Cosworth M2 272 11
Intake Costworth M3 280 11.6
Exhaust Costworth M3 272 11
Intake FP 4R 267 221 11.1 108
Exhaust FP 4R 275 228 10.9 113
Intake FP 5R 279 233 12.1 110
Exhaust FP 5R 285 238 11.8 114
Intake GSC S1 268 216 11 107
Exhaust GSC S1 268 220 10.5 113
Intake GSC S2 274 230 11.2 107
Exhaust GSC S2 274 230 11 113
Intake GSC S3 280 238 11.7 109
Exhaust GSC S3 280 235 11.7 115
Intake Greddy 260 10.8 110
Exhaust Greddy 260 10.3 112
Intake HKS Step 1 264 10.8 110
Exhaust HKS Step 1 264 10.2 110
Intake HKS Step 1 272 10.8 110
Exhaust HKS Step 1 272 10.2 110
Intake HKS Step 1 280 10.8 110
Exhaust HKS Step 1 280 10.2 110
Intake HKS Step 2 274 11
Exhaust HKS Step 2 278 11
Intake JUN 264 264 10.5 110
Exhaust JUN 264 264 10.5 115
Intake JUN 272 272 235 10.8 110
Exhaust JUN 272 272 235 10.8 115
Intake Kelford TX258 258 208 10.5 107
Exhaust Kelford TX258 264 220 10.5 111
Intake Kelford TX264 264 216 11 107
Exhaust KeIford TX264 260 216 10.35 113
Intake kelford TX272 272 226 11 107
Exhaust Kelford TX272 272 226 11 113
Intake Kelford TX280 280 233 113 107
Exhaust Kelford TX280 276 230 11 115
Intake Kelford TX288 288 242 12 105
Exhaust Kelford TX288 280 238 11.5 117
Intake Kelford TX276HL 276 234 123 106
Exhaust Kelford TX276HL 272 230 12 115
Intake Kelford TX284HL 284 242 12.5 106
Exhaust Kelford TX284HL 280 238 12 116
Intake kelford TX294HL 294 250 12.5 106
Exhaust Kelford TX294HL 292 244 12 117
Intake Piper Drag Race 290 11.99 106
Exhaust Piper Drag Race 290 11.99 106
Intake Piper Race 274 11.99 106
Exhaust Piper Race 274 11.99 106
Intake Piper Race 274 11.51 106
Exhaust Piper Race 274 11.51 106
Intake Piper Race 270 11.51 106
Exhaust Piper Race 270 11.51 106
Intake Piper Fast Road 272 10.8 108
Exhaust Piper Fast Road 256 10.16 107
Intake Piper Fast Road 264 11 108
Exhaust Piper Fast Road 260 10.1 107
Intake Piper Ultimate Road 265 11.51 108
Exhaust Piper Ultimate Road 265 10.8 107
Intake Piper Rally 265 11.51 108
Exhaust Piper Rally 265 11.51 107
Intake Piper Group A 265 11.51 106
Exhaust Piper Group A 267 9.61 108
Intake Revolver 262 222 11.4 109
Exhaust Revolver 264 223 11.5 111
Intake Skunk2 Tuner Series 264 10.8
Exhaust Skunk2 Tuner Series 272 10.2
Intake Tomei PON 260 10.7
Exhaust Tomei PON 260 10.2
Intake Tomei PON Type R 270 10.7
Exhaust Tomei PON Type R. 270 10.2
Intake Tomei PRO 270 11.5 110
Exhaust Tomei PRO 270 11.5 115
Intake Tomei PRO Solid 230 11.5
Exhaust Tomei PRO Solid 230 11.5
Intake Tomei Pro Solid 290 11.5
Exhaust Tomei Pro Solid 290 11.5

Tuesday, 27 November 2012

Forged Pistons , Ring end gap & Piston clearance by Arias

Minimum Ring End Gaps And Clearance

Ring Application Minimum End Gap Per Inch Of Bore
Premium Top Rings Blown Fuel, Alky, Gas 0.008

Injected Fuel 0.007

Blown Fuel, Alky, Gas 0.0075

Blown Gas, Street 0.0065

Nitrous Less 250hp 0.0065

Heavy Nitrous 250hp+ 0.0075

Na Alky, Gas 0.0055

N.a Gas, Street 0.005

Cast Iron Second Rings Blown Fuel, Alky, Gas 0.006

Na Alky, Fuel 0.005

Na Gas 0.004

Third Groove Oil Control Rings Upper And Lower Rails .015"  min.

Recommended Piston Clearances

Minimum Piston To Valve Normally Aspirated Int. 090"   Exh. .110"

Blown Int. .125"  Exh. .175"

Minimum Piston To Head Steel Rods .040"-.050"

Source :

Monday, 26 November 2012

Mitsubishi Spark Plug list




Eng. size

Dates of release

Plug type
3000 GT6G73.0 97-PFR6J-11-1,1
3000 GT6G72 MPI TC3.0 95-PFR6J-11-1,1
3000 GT6G72/T DOHC3.009.92-PFR6J-11-1,1
Carisma4G92 SOHC1.6 97-BKR6E-11141,1
Carisma4G93 SOHC1.8 97-BKR6E-11141,1
Carisma GDI4G93 GDI1.809.97-PZFR6B-0,8
Carisma 1600 DAO4G921.609.95-BKR6E-11141,1
Carisma 1800 DAO4G931.809.95-BKR6E-11141,1
Carisma 1800 DAO4G931.809.95-BKR6E-11141,1
Champ 13004G131.3 94-BP5ES 80,8
Champ 15004G151.5 94-BPR5ES-11-1,1
Colt 12004G111.2 - 84BPR5ES 60,8
Colt 1200 C104G161.2 85- 88BPR6ES 20,8
Colt 13004G11.3 97-BPR5ES-11-1,1
Colt 13004G131.3 95-BPR5ES-11-1,1
Colt 13004G131.3 89-BPR6ES 20,8
Colt 13004G131.303.96-BUR6EA-11-1,1
Colt 13004G13 / MPI1.3 92-BPR5ES-11-1,1
Colt 13004G13 / MPI Cat.1.3 93- 94BPR6ES-11131,1
Colt 14001.4 - 87BPR6ES 20,8
Colt 15004G151.5 94-BP5ES 80,8
Colt 15004G151.5BPR6ES 20,8
Colt 15004G15 Cat.1.5BPR6ES-11131,1
Colt 16004G9 MVV1.6 97-BKR5E-11-1,1
Colt 16004G9(not MVV Magermix)1.6 97-BKR6E-11141,1
Colt 16004G921.603.96-BKR6E-11141,1
Colt 16004G921.6 92- 93BKR6E-11141,1
Colt 16004G92 MPI1.6 94- 95BKR6E-11141,1
Colt 16004G92 MPI MVV1.6 95- 96BKR5E-11-1,1
Colt 16001.6BPR6ES 20,8
Colt 1600 16V4G921.612.91-BPR6ES 20,8
Colt 1600 Turbo1.6 86- 88BPR6ES 20,8
Colt 1600 Turbo1.6 (85)BPR7ES190,8
Colt 18004G671.8BPR7ES190,8
Colt 18004G67 Cat.1.8BPR7ES190,8
Colt 1800 GTI 16V4G93 MPI1.8 94-BKR6E-11141,1
Cordia4G321.6 -84/86-BPR5ES 60,8
Cordia4G321.6 (85)BPR6ES 20,8
Cordia Turbo4G321.6 - 84BPR6ES 20,8
Cordia Turbo4G62 / G62B1.8 85-BR7ES-0,8
Diamante 30006G72 MPI DOHC3.0 94-BK6E-0,8
Diamante 30006G72 MPI SOHC3.0 94-BPR6ES-11131,1
Eclipse4G62.0 97-BPR6ES-11131,1
Eclipse 20094G63 MPI DOHC2.0 91-10.95BPR7ES190,8
Eclipse 2009 D304G632.011.95-BUR7EA-11-1,1
Expo 1800 LRV4G93 MPI1.8 94-BKR5E-11-1,1
Expo 2400 / LRV4G64 MPI SOHC2.4 94-BKR5E-11-1,1
Galant4G62.0 97-BKR6E-11141,1
Galant V66A132.5 97-PFR6G-11-1,1
Galant V6 24V6G73 MPI2.5 95-PFR6J-11-1,1
Galant 12001.2 - 84BPR6ES 20,8
Galant 14001.4 - 84BPR5ES 60,8
Galant 16004G321.6BPR6ES 20,8
Galant 18004G371.8BPR6ES 20,8
Galant 18004G37 Cat.1.8 - 91BPR6ES-11131,1
Galant 18004G37 Cat.1.8 92-BPR7ES-11-1,1
Galant 18004G931.8 94-BK6E-0,8
Galant 18004G93 MPI1.8 94-BKR6E-11141,1
Galant 2009 Cat.2.0 92-BPR7ES-11-1,1
Galant 20094G632.0 93-BK6E-0,8
Galant 20094G632.0 96-BKR6E-11141,1
Galant 20094G632.0BPR6ES 20,8
Galant 20094G632.0 92-BPR7ES-11-1,1
Galant 20094G63 Cat.2.0BPR6ES-11131,1
Galant 20094G63 MPI2.0 94-BKR6E-11141,1
Galant 20094G63D2.0 92-BPR6ES 20,8
Galant 2009 V66A12 MPI 24V2.0 93-PFR6J-11-1,1
Galant 24004G64 MPI DOHC2.4 94-BPR6ES-11131,1
Galant 24004G64 MPI SOHC2.4 94-BKR6E-11141,1
Galant 2500 V6 24V2.5 93-PFR6J-11-1,1
Galant Dynamic4G632.0 91-BPR6ES 20,8
L2004G321.6 92-BPR5ES 60,8
L2004G32 Cat.1.6BPR6ES 20,8
L2004G542.6 - 92BPR6ES-11131,1
L2004G54/B2.6 93-BPR6ES-11131,1
L2004G632.0 92-BPR6ES 20,8
L2004G632.0 - 92BPR7ES190,8
L2004G64 MPI2.4 94-BPR6ES-11131,1
L200G54B2.6 95-BUR6EA-11-1,1
L3004G321.6BPR5ES 60,8
L3004G331.4 94-BP6ES 40,8
L3004G632.0BPR5ES 60,8
L3004G632.0 92-BPR6ES 20,8
L3004G63 Cat.2.0 92-BPR6ES 20,8
L3004G63 FBC2.0 95-BKR5E-11-1,1
L3004G63 MPI2.0 95-BKR5E-11-1,1
L3004G64 Cat.2.4 92-PGR6A-11-1,1
L4004G63 MPI2.0 95-BKR5E-11-1,1
L4004G64 MPI2.4 95-BKR5E-11-1,1
Lancer 12004G111.2 - 84BPR5ES 60,8
Lancer 12004G161.2 85-BPR6ES 20,8
Lancer 13004G11.3 97-BPR5ES-11-1,1
Lancer 13004G131.310.92-BP5ES 80,8
Lancer 13004G131.3 89- 92BPR6ES 20,8
Lancer 13004G131.303.96-BUR6EA-11-1,1
Lancer 13004G131.303.96-BUR6EA-11-1,1
Lancer 13004G13 Cat.1.3 -09.92BPR6ES 20,8
Lancer 13004G13 MPI1.310.92-BPR5ES-11-1,1
Lancer 14004G121.4 - 84BPR5ES 60,8
Lancer 15004G151.5 93-BP5ES 80,8
Lancer 15004G151.5 85- 92BPR6ES 20,8
Lancer 15004G15 Cat.1.5 86- 92BPR6ES-11131,1
Lancer 15004G91 MPI1.5 94-BK6E-11-1,1
Lancer 16004G61 DOHC1.6 90-09.92BPR6ES 20,8
Lancer 16004G9 MVV1.6 97-BKR5E-11-1,1
Lancer 16004G9(not MVV Magermix)1.6 97-BKR6E-11141,1
Lancer 16004G92 MPI1.610.92-BKR6E-11141,1
Lancer 16004G92 MVV1.6 94-BKR5E-11-1,1
Lancer 16001.6 - 84BPR5ES 60,8
Lancer 1600 Turbo4G32T1.6 86- 88BPR6ES 20,8
Lancer 1600 Turbo4G32T1.6 (85)BPR7ES190,8
Lancer 1600 Twin Carb.1.6BPR6ES 20,8
Lancer 18004G37 Cat.1.8BPR6ES-11131,1
Lancer 18004G671.8BPR7ES190,8
Lancer 1800 16V4G93 MPI1.8 93-BK6E-0,8
Mirage4G15 MPI1.5 94-BPR5ES-11-1,1
Mirage4G93 MPI1.8 94-BKR5E-11-1,1
Montero V6 30006G723.0 91-BPR5ES-11-1,1
Pajero4G642.4 97-BPR6ES-11131,1
Pajero6G72 12Ventiler3.0 97-BPR5ES-11-1,1
Pajero6G72 24Ventiler3.0 97-PFR6J-11-1,1
Pajero6G743.5 97-PFR5J-11-1,1
Pajero 24004G642.403.91-BPR6ES-11131,1
Pajero 26004G542.6BPR5ES 60,8
Pajero 26004G54 Cat.2.6BPR5ES-11-1,1
Pajero 26002.6 92-BP6ES-11-1,1
Pajero 3000 V66G723.0 89-BPR5ES-11-1,1
Pajero 3500 V66G74 DOHC3.504.94-PFR6J-11-1,1
Sapporo 12001.2BPR6ES 20,8
Sapporo 14001.4BPR5ES 60,8
Sapporo 16001.6BPR5ES 60,8
Sapporo 1600 Twin Carb.1.6BPR6ES 20,8
Sapporo 20092.0BPR6ES 20,8
Sapporo 24004G642.4BPR7ES-11-1,1
Sapporo GSR2.003.81-11.84BPR7ES190,8
Sapporo Turbo2.003.81-11.84BR7ES-0,8
Sigma V66G72 DOHC 24V3.0 91- 93PFR6J-11-1,1
Sigma V66G72 SOHC3.0 91- 93BPR6ES-11131,1
Sigma 30006G72 MPI V63.0 94-BPR6ES-11131,1
Sigma 30006G72 MPI V6-24V3.0 94-PFR6J-11-1,1
Space Gear4G63 MPI2.004.95-BKR5E-11-1,1
Space Gear4G64 MPI2.404.95-BKR5E-11-1,1
Space Gear4G692.0 97-BKR5E-11-1,1
Space Runner4G931.8 97-BKR6E-11141,1
Space Runner 18004G931.8 94-BK6E-0,8
Space Runner 18004G931.809.91- 92BKR6E-11141,1
Space Runner 18004G93 MPI1.8 94-BKR6E-11141,1
Space Wagon4G632.0 97-BKR5E-11-1,1
Space Wagon 86- 88BPR6ES 20,8
Space Wagon (85)BPR7ES190,8
Space Wagon 18004G371.8 89-BPR6ES 20,8
Space Wagon 18004G931.8 94-BK6E-0,8
Space Wagon 18004G931.809.91- 93BKR6E-11141,1
Space Wagon 18004G93 MPI1.8 94-BKR6E-11141,1
Space Wagon 20094G63 Cat.2.0 89-BPR7ES-11-1,1
Space Wagon 20094G63 MPI Cat.2.0 93-BKR6E-11141,1
Space Wagon 2009 4WD2.0 89-BPR7ES190,8
Starion 20092.0BPR7ES190,8
Starion 2600 TurboG54B Cat.2.6 89-BPR6ES-11131,1
Starion Turbo2.0BR7ES-0,8
Tredia1.6 -84/86-BPR5ES 60,8
Tredia1.6 (85)BPR6ES 20,8
Tredia Turbo1.6 - 84BPR6ES 20,8
Tredia Turbo1.8 85-BR7ES-0,8

Cable Plug Information


This is to help all those looking to upgrade their ignition wires and are not sure what brand they would like to buy.

The following is the resistance measured in ohms/ft by each major ignition wire distributer.

(low = good, high = bad)

MSD Ignition 8.5mm Super Conductor (40-50 ohms/ft)
Accel Thundersport (150 ohms/ft)
Taylor 8mm Spiro Pro (350 ohm/ft)
Aurora ignition wire set (400 ohms/ft)
Vitek Performance Cables (their web site does not mention resistance, but John Monnin measured them at about 800 ohms/ft; the label under Vitek's braiding says "Magstar Gold 8mm High Performance S-4 Stainless Steel Mag Wire" - thanks John!; Magstar wires are manufactured by Wiretec)
Wiretec Magstar Gold (800 ohms/ft as measured by John Monnin)
NGK Resistor Spark Plug Wire Set (2600 ohms/ft)
Mitsubishi factory wire sets (3000++ ohms/ft)
Car Quest brand wire sets (3000++ ohms/ft - Thanks to Bret for measuring these wires.)
Magnecor KV85 (6000++ ohms/ft)

VR4 vs Evo Layout

VR4 and Evo has different layouts, different intake manifolds. The Coil plugs of the VR4 are longer as the coils sits down below compared to the evo.

Credits of pictures to VTEC_THIS from dsmtuners.

4G63 Spark Plugs Info

The Spark Plug FAQ: or "What spark plugs should I use in my DSM?"

Every few weeks, sometimes even every few days, there comes a thread where a new owner of a DSM asks what the best spark plugs are for his or her car. More rare, but still seen every once in a while is the question posed where the owner is having problems with the car stumbling, hesitating, losing power, and otherwise not running quite right. In some cases, it is due to not running the correct spark plug or plug type. In this FAQ, I'll try to depict a few different types of spark plug and the pro's and con's of each. There's a fairly definite answer to the question you may have: "What spark plug should I use in my DSM," but we'll get to that later.

Source :

First, a few pictures of some various spark plugs you may be currently using, have used in the past, or have considered using. Note: The following applies mostly to turbo DSM's and may not reflect usage in a non-turbo application.

#1. The NGK BPR6ES. This is what the majority of DSM'ers who don't have too many mods or are running fairly low boost will tend to use.

#2. This is the NGK BPR6EKN. This is what you'll most likely be offered if you walk into an auto parts store or dealership and ask for plugs for your turbo DSM, because this is the plug called for in the Owner's Manual and the shop manual. It was the standard factory plug for turbo DSMs. Notice the dual electrode. It's fairly pointless, since the spark will only jump to one of them, but these are an option for our cars, although not the best option. Unless part of your shop's income is generated by selling spark plugs, of course.

#3. This is a Bosch Super plug for the DSM 4g63t. It's a copper plug, fairly similar to the NGK, more or less. You may be offered this plug when you go to an auto parts store.

#4. This is a Bosch Platinum plug. This is another option you may be given when you go to your local auto parts store. It has been the experience of nearly ever DSM'er that you should avoid platinum plugs at all costs in turbocharged applications. The salesperson will most likely tell you that platinum plugs last a long time, or maybe they're on sale. It doesn't matter. They simply are not the best, nor worth the cost, for our cars.

A note about the pic: Do you notice anything missing that was visible in the previous pictures? That's right. The center electrode is amazingly small, nearly invisible. Below are two internal diagrams of the Bosch plugs (copper and platinum) from the exterior of their respective boxes.

#5. Here is a Bosch Platinum +4. It has four electrodes and a small platinum center electrode.

I don't have any pictures of any iridium plugs because they're special order where I work, and we didn't have any in stock. This isn't suprising because of their cost. For the price of a single iridium plug, you could have an entire set of standard copper plugs with money left over for a gapping tool and a frosty beverage.

One of the most frequently asked questions that crops up often here on DSMtuners is: "What kind of spark plug should I use in my (turbo) DSM?"
Use NGKs. They are the best for our cars. For some unknown reason, our cars just 'prefer' them.


An important feature of spark plugs that often goes unnoticed, or is often misunderstood, is what is known as the "heat range" of a spark plug. The spark plug must dissipate heat. Different heat ranges of spark plugs dissipate heat at different rates, which allows people to use different plugs for different applications. The plugs do not create heat, but instead remove it. The heat is transferred through the metal shell of the plug, to the head, where it is removed by the oil and water passages in the head. The way it does so is best shown by this diagram from NGK's website:

Different companies sometimes use different methods for determining the heat ranges of their plugs. NGK, for example, uses lower numbers for hotter plugs and higher numbers for colder plugs; i.e. BPR6ES plugs are hotter than BPR7ES plugs. Using too cold of a plug in your car will lead to fouling, but using too hot of a plug may lead to a hot-spot developing on the plug surface, which may result in pre-ignition/detonation. The ideal situation is to use the coldest plug possible without fouling.

Here's a comparison of three spark plugs made by NGK. At first glance, you may not notice a difference. Upon closer inspection, you may find that the shape and thickness of the white insulator around the center electrode thickens as the plug's heat range goes colder. In addition, the insulator is in contact with more of the outer shell where the threads of the plug are as the plug's range goes colder. On the left is a BPR5ES, in the middle is a BPR7ES, and on the right is a BPR9ES.

The more contact the insulator has with the outer shell, the more heat can be transferred out of the plug and into the head. Heat doesn't travel through air as well, so in a plug with less contact with the outer shell, the core of the plug stays hotter.

Another frequently asked question seen here (now that you know you need NGKs) is: "What heat range of NGK do I need for my (turbo) DSM?"
There are no set rules, but there are guidelines:
-For stock to near-stock cars, BPR6ES.
-For mildly modified to - heavily modified or high-boost, use BPR7ES.
-For heavily modified, high boost applications, use BPR8ES.
If plug fouling occurs, go one step hotter and monitor performance and results.

Stock car, T25/14b, 12-15 psi, upgraded intake/exhaust: 6ES
16g, 20 psi, water/meth injection : 7ES-8ES
GT35R, nitrous, the works: 8ES-9ES-10ES


Copper, Platinum, Iridium. (What's next, Adamantium?) What's the right one for you? As mentioned earlier, the vast majority of DSM'ers will swear by standard NGK copper plugs. Platinum is not as good a conductor as copper, but it's harder so it lasts longer. Iridium is also very hard, but it's also very rare, which makes it expensive. The consensus regarding iridium plugs is that while they work, they're not worth the price when standard $2/each copper plugs work more or less the same. Even though platinum plugs are closer in price to copper plugs, it's been my experience along with many other members, that running platinum plugs caused fouling, stumbling, hesitation, a loss of power, a decrease in gas mileage, and poor idle. Switching to standard NGK copper plugs solved the problems immediately.

Here's the answer to one of those common questions: "My car stumbles/hesitates/has no power/idles oddly/has lost gas mileage/does not perform well..."
If you are running platinum spark plugs and notice that your car isn't running right.... take them out and put in NGK BPR6ES spark plugs and see if your situation improves.


Another common question is in regards to the proper gap of a spark plug. This refers to the space between the center electrode and the side electrode. The average auto-parts store computer will usually suggest a gap for each spark plug that they have in their computers. However, in most cases, the best gap to use is the one specified by the manufacturer of your car. In the case of turbo DSM's, many people choose to gap their plugs to .028". DSM'ers have had good experiences with slightly larger gaps (.030-.032") as well as with smaller gaps (.026"). The computer where I work suggests a gap of .032" for the spark plugs for our cars.

Spark plugs do not come from the factory pre-gapped. You may open a spark plug up and find that it meets your gap needs, but this does not mean that the next identical spark plug will have the exact same gap. To be sure, manually gap each spark plug you install. There are several tools to help you measure a spark plug's gap. Here are three of the most common: a gapping disc ($.99), a blade measurer ($3) and a wire-gapper ($3). What you use is your preference. Many people say that the ramp-style gappers are not as accurate. They'll work in a pinch, but the wire and blade gapping tools are preferred.

Here's an answer to another commonly asked question: "What should I gap my spark plugs to?"
Gap your plugs to .028"

My good friend Anthony (DSMunknown) has brought to my attention that there has been some discussion in past years regarding the gap of spark plugs opening up over time, possibly due to long projected tip or high exhaust gas temperatures. If you race or dyno your car regularly, checking your spark plug gaps on a regular basis (once ever 5 dyno pulls or once every 3-5 1/4 mile runs, or so) and monitoring whether they are opening up or not. If they are, you'll need to replace or re-gap more often than drivers who daily-drive their cars. More info on this will be forthcoming as research is conducted and reported.

To sum up: In general the BEST spark plug for our cars is the NGK BPR6ES gapped to .028", varying heat range depending on modifications.

For more information:
NGK Spark Plug Information
Decoding NGK Spark Plug part numbers.
Reading spark plugs
An in-depth look at spark plugs.
A VERY in-depth look at plug, brought to you by our cousins, the Stealth/3kGT.
A conglomeration of threads discussing different experiences with spark plugs.

Friday, 23 November 2012

Ferrea Performance Valves by Onedirt

We often do not change our valves keeping in our minds that our OEM valves is all we need. To extract the maximum horsepower of the head, valves places an important role. Most common valves comes from Ferrea and Supertech. Below is an article by Andrew Wolf from

Source :

High performance engines deserve a set of high performance valves, and because we’re in the business of squeezing the most performance possible out of any engine combination, valves are very much an important aspect to focus upon. And why not? There’s plenty of horsepower to be made from a good set of valves and a proper valve job. Everything from the material selection, the valve and stem sizes, and the back cuts play a significant role in mating valves to your engine that not only meet the needs of your specific application, but make the most of it with great flow that leads to increased horsepower and efficiency.
In this guide to performance valves, we’ll take a look at variables like valve and stem sizing, materials, backcuts, and the technology that exists behind racing valves with one of the historic names in the industry, Ferrea Racing Components. Founded in the late 1960′s in Argentina by Dan Urrutia and Horacio Ferrea, the valvetrain manufacturer has remained at the forefront of cutting edge valve technology for more than 40 years. Today, the business remains with the Ferrea and Urrutia families, and we sat down with Director of Marketing and the third generation figure behind the renowned business, Zeke Urrutia, to gain some insight on valve technology and proper valve selection from the perspective of an industry leader.

Selecting The Proper Valve Material
When discussing the material for your valve selection, it generally comes down to a choice between several variations of stainless steel, which are most common in performance street and light duty racing applications for their durability and price, various forms of alloys, and the high-end, lightweight, titanium valves that are typically found in racing engines that receive regular maintenance.
“One of the primary decisions to take into account when selecting a valve is to determine the material for the specific application, be it stainless steel – which there are basically seven to eight different stainless materials – and then the other option, which would be titanium,” said Urrutia. “In some applications, you can get involved in using titanium, but in others, such as streets cars that are driven regularly, gas-driven cars, and anything that has very high temperatures, then steel is preferred.”

A pair of Ferrea's Small Block Chevrolet stainless steel valves. Ferrea manufactures valves from several materials and blends for different purposes and budgets, including titanium, stainless steel, and various types of alloys.
Titanium – When Nothing Less Will Do
Titanium valves are the material of choice in professional drag racing, oval track, road racing, and other venues where winning often outweighs the cost, due to their light weight and strength along with the allowance for more radical cam profiles and added power potential. With a price tag that is often two to three times that of the highest-quality stainless steel valves on the market, they aren’t for the faint of heart, nor the weekend warrior trying to race on the cheap.
“With titanium, there is only a certain market that we and our competitors dabble with, and that’s the high end,” says Urrutia. “There is titanium that we manufacture for the OEM’s though; primarily for the ‘Big Three.’ Titanium really involves a whole different process for these OEM-built engines. An example would be the popular GM LS line of engines, and specifically the Corvette LS7, which usually falls into a certain criteria where those are very low mileage cars. The cycle life of titanium valves is very marginal – you don’t get much time out of them. And if you do, you’re getting involved with some pretty exotic coatings and maybe put another 20-30 percent more life on them, but it’s marginal for what it’s worth.”
As such, the use of titanium is mostly limited to serious, cost-is-no-option racing teams that typically change out the valvetrain components on a regular basis. Urrutia explains that NHRA Pro Stock teams, for example, will often swap out the valves at least every other race and replace them and other drag racing applications might see between three and fives races before the valves are swapped out. While the valves still have a limited amount of life in them after that short time of use, for these teams it’s more of a security thing to keep their engines alive and in contention. Truth be told, not even the manufacturers can give an approximate timetable of just how long a titanium valve will last and when to replace them.

This view shows the difference in the faces of a set of LS1 valves (at left) and Small Block Chevrolet valves.
Stainless Steel Valves
When looking at the category of stainless steel valves, the primary advantage is the ability to not only withstand higher levels of heat and the strain that accompanies that heat, but also includes the tensile strength that the valve can handle as well. The materials or blends that are included in stainless, such as alloys comprised of nickel, chromium, and other materials will allow for a specific temperature on the valves, as well as a certain tensile strength. Both of these factors favor applications like large cubic inch naturally aspirated engines, or with the use of power adders including superchargers, turbochargers, and nitrous oxide. As such, the selection of the blends of the stainless material becomes important to getting the most from your engine.
“Stainless steel is a material as an identity for longevity. It holds itself very well, has properties that last very, very long, and you can get into very high temperature environments; especially on the exhaust side,” says Urrutia. “Stainless has become somewhat of an identity for guys that are building an engine, running it maybe at weekly circle track or drag race events, and depending on the build, can get very long durations out of them.”
Ferrea offers three different primary product lines of stainless steel and alloy valves: the Competition Plus Series, the 6000 Series, and the 5000 Series. Urrutia points out that within the Competition Plus line, there are four to five different stainless materials to choose from. “It mainly entails the exhaust valve side, because what really perturbs any valve is the heat and spring pressure. Those are really the two main factors that you have a big area of weakness on an exhaust valve. Bang for the buck, it’s an area where most engine builders venture first, and then see if there’s a possibility for titanium if their pockets are that deep.”
The 5000 Series is more performance oriented toward street rods, muscle cars, and similar applications that are often cruised on the weekends or driven for extended periods of time. The 6000 Series represents the middle ground between the other two lines, which is aimed at the cost-conscious bracket racer or weekly oval and dirt track racer with engines that often utilize high spring pressure, big roller camshafts, and large compression ratios that lack the use of power adders. Both of these lines are available only in stainless steel, and once you evolve to the Competition Plus series, there are four to five variations of stainless steel that utilize exotic alloys.
Ferrea utilizes three to four differing blends of stainless steel that make up a particular valve. The differences between the differing blends is primarily the heat range to which they can withstand.
The first among those is what’s known as an EV8, which Urrutia describes as being incredibly strong with great memory and because of it’s wide use in all forms of manufacturing, is a common blend in foundries around the world and quite popular for valves – especially on the intake side. EV8 is comprised of chromium and nickel and Ferrea adds tungsten to the mix to make it suitable as an exhaust valve, as well. Also on the intake side is IN751 – an inconel -
From there you get into some more exotic materials and alloys involving exhaust valves. These include VB54, a high-heat stainless steel blend with a high nickel base that’s used exclusively for exhaust valves for combinations composed of forced induction and nitrous oxide. Also on the exhaust side is Nickelvac N80 that sports nickel and tungsten for handling even higher temperatures – upwards of 1,850 degrees fahrenheit. And finally, you have what Urrutia calls the ultimate of their stainless steel exhaust valve blends; Nickelvac 800. These are used in large diesel engines, Top Fuel Dragsters and Funny Cars, and turbocharged road racing vehicles where the most extreme of valvetrain environments and heat exist.

The bowl-shaped heads on a set of Ford intake and exhaust stainless steel valves.
Inconel and Sodium-Filled Valves
A blend that Ferrea uses on both the intake and exhaust side is IN751, which is an inconel material. Used in an engine that sees high heat on the intake side, this material will hold its memory and integrity quite well and is rather flexible. The term “memory” refers to the valve’s ability to shift and move in different positions under extreme loads without encountering fatigue issues.
“Inconel in this day and age is used a lo in our industry; almost as much as titanium. Inconel was brought on by the avionics industry and has made it’s way to the racing, as may things do. Inconel is categorized under our Super Alloys, but we actually create our own blends to that make it handle high temperatures that much better. so instead of handling in the neighborhood of 1,800 degrees, we’re looking at about 2,400 degrees.
Ferrea also manufactures sodium-filled valves, albeit on their OEM side where these valves are primarily limited to. Sodium bases used in these valves are only tested to around 1,600 degrees, which most racing and high performance engines exceed. The liquid sodium travels up and down the stem of the valve, and at the boiling point, the liquid turns to gas. You then essentially have a valve with a hollow neck and excessively high temperatures, the chance of failure is very high.
However, the benefit of the sodium-filled valve comes in the form of added longevity due to the cooling properties of the sodium, and in street cars where temperatures are kept in check and hundreds of thousands of miles are expected, these are key.

The valve starts as a solid rod, heated on one end and then compressed to form the valve's face.
Hollow Stem Valves
“Something that we’ve enhanced in the last four to five years is the hollow-stem stainless valve, which we’ve been continuing to move in the direction of lighter and lighter valvetrain mass as a whole,” explains Urrutia.
The components related to the valve such as retainers, lifters, the camshaft, and the valvetrain as a whole as a mass adapt to the lighter valve – such as titanium or the lighter hollow stem stainless – much better harmonically. And thus component-wise, from a harmonics standpoint, the result is an engine that is far more stable. In that same regard, the power band becomes much smoother.
Says Urrutia “if you look at the durations of the power bands, whether it’s on a dyno or a spintron, the windows are shortened up a lot closer because you’re getting to that point that much faster with the lighter valves. If you take just the valve spring for example combined with a titanium or light stainless valve, the spring would see a lot more life because the mass driving the spring is the valve and it’s that much lighter. Thus, the spring doesn’t have to work itself as hard.”

Ferrea's Competition Plus Series Valves are a hollow stem design and have a reputation as the industry's most reliable extreme duty valve.
Ferrea equates their hollow stem valves at about 22% lighter than a standard stainless steel valve, and while not as light and therefore not as easy on the correlating valvetrain components as the expensive titanium, the advantages are certainly present. At present, Ferrea produces only stainless steel valves in the hollow stem variety, but Urrutia indicates that he and his team are working to develop them in titanium, as well.
Lock Styles
An element of a valve design that is commonly overlooked and rarely discussed are locks the varying styles of locks. The locks hold the retainer in place and come in various designs including standard, radius, square, and double locking mechanisms. The locks are two-piece and while a very small component itself, represents a rather important role in the overall picture of a valvetrain as it holds the valve in place. The valve designs are specifically designed based on the style of lock being used.
“We got into radius grooves nine to ten years ago and what amazes us is that they haven’t become all that popular, but they are much, much better than a square groove. Anything that is round and has round edges is always stronger on a material base, and thus you can prolong the life of the part longer than one that is square,” explains Urrutia.

Above are the varying styles of locks found on (from L to R) Ford, Big Block Chevrolet, hollow stem LS1 Small Block Chevrolet, and Small Block Chevrolet valves.
Ferrea finds there to be about 30% more life in a radius lock compared alongside a square lock.
“Our square lock has been enhanced the last several years to where if you look at it, it’s not a true square lock. It has small radius corner edges on the top and bottom.
So What Are The Differences?
The information above can be best summed up by saying that the specific use of the various materials that valves are manufactured from is a game of tradeoffs. For the high-end racing applications where the ultimate in performance is key and maintenance is consistently performed, titanium valves are preferable. These come at a twofold cost, however. Due to their naturally shorter lifespan, you’re looking at not only the high one-time cost of a set, but the repeated cost of replacing them on a regular basis as needed. For those that can get away with the slightly lesser performing steel and alloy valves, the costs are significantly reduces and longevity is considerably longer; perhaps anywhere from one to three seasons of continual use.
“Selecting materials really comes down to the three main categories. The first is the application, the second being the fuel that you intend to use in the engine, and three is the duration of that application, or the longevity that the valvetrain is expected or desired to live,” explains Urrutia.
Properly Sizing The Valves And Stems

Ferrea valves (from L to R) Ford, Big Block Chevrolet, hollow stem LS1 Small Block Chevrolet, and Small Block Chevrolet valves feature varying stem lengths depending upon cylinder head make and design.
There are two main factors that need to be kept in mind when discussing sizing of both the intake and exhaust valves for a specific engine. Cylinder head manufacturers typically design an industry standard size for valves, which entails the OEM engines with a standard size for small blocks, big blocks, and smaller sport compact engines. All of that obviously involves it being just that: a standard. On the second point, according to Urrutia, “You open yourself up to a pretty sizable window, where the sizes can vary drastically for each typical cylinder head, depending on how far and between someone is willing to go with the port work on the head and flow enhancements.”
Urrutia continued, “A standard intake valve for a small block Chevrolet is 2.020-inches and the exhaust is 1.600. But, you can get in there and open up that area on the intake – for example to 2.050, 2.080. 2.100, 2.125 and even as large as 2.200. You open yourself up to where you can expand that much more in sizing depending upon how much you’re going to modify that head and whether it’s being placed on a mild race engine, full out race engine, or something completely hot rod performance-oriented.”
Valve Stems – Size Does Matter
Likewise, valve stem sizes are dictated by what is being looked at in todays world as a standard of 11/32-inch. Stem sizes, however, are becoming much smaller today due to the materials and processed used in their design, allowing manufacturers to not only produce valves with stems that are not only smaller, but lighter in that same regard.
“I would say that the two main sizes that have become very, very popular in this day and age would be 11/32 being one, and 5/16 being another, explained Urrutia. “Those are really two of the pivot points that still drive our market. And then you obviously get into some smaller ones, found in some foreign engines. Some of the LS engines have also gone to 8mm, which is just a tad bit larger in size than a 5/16, so it’s relatively close in the range that they’ve really looked at and determined for use in OEM engines. If you look back ten to fifteen years ago, everything was pretty much still 11/32 somewhat, and 3/8 was still very popular back then. Today, 3/8 is starting to become a little less popular and common.”
Ferrea’s 6000 Series Competition Valves are designed for excellent reliability in engines with high spring pressures and roller cams.
The stem of the valve has to be in proportion to the head size of the valve, meaning that if the stem is a specific size, the head can only be designed to a certain size as well. For example, a valve with an 11/32 and a 2.800 or larger head diameter would incur issues of what is known as deflection, in which abnormal areas of the valve experience more flex than usual with smaller head diameters relative to the proportionate size of the stem. Essentially, the size of both coincides with one another. And it’s these two elements of the design of a valve that play a large role in the lasting survival or failure of the valve over a period of time.
Some manufacturers on the market offer valves that are longer than stock, and others offer valves with undercut stems that leads to increased flow. One point important to note is that nearly all factory replacement and aftermarket valves have a .001-inch taper down the length of the valve – narrower at the base of the head – to accommodate expansion created by the heat that that would otherwise cause galling, or wear due to friction between the metals.

Machining the backside of the valve, known as back cutting, is one element that can most improve the overall flow of air and therefore create added horsepower.
Valve Backcutting
The one aspect of a valve that plays the biggest role in improved flow and horsepower is the backside of the valve, which can be modified – to an extent, obviously – through a process known as backcutting. This extra machining of the valve correspondent to the angles around the valve seat makes for a smoother transition and increased airflow. Many of the high performance and high-end racing valves on the market already incorporate back cuts into their design, and other valves, such as OEM replacements, can benefit from the process. In doing so, you prevent flow separation from the valve as air flows over them. Flow separation causes turbulence and therefore less-than-stellar flow.
Back cuts are very relative to port design,” explained Urrutia. “Both the port design and the back cut coincide with one another. Multiple angles on the port, particularly on the seat, typically enhance and improve back cuts on valves. In this industry, some do a three-angle, and some do as much as a five-angle valve job on the initial seat on the port. That would typically determine at that point what angle to adjust on the valve itself for a back cut. Back cuts can be as minimum as half a degree or can be as large as one-degree difference.” This can be very critical when you get into multiple seat angles that are done on the cylinder head port, and falls into mostly the higher-end racing engines that are looked upon in very fine detail and gaining as little as one or two horsepower can be a monumental achievement.

A view of the backside of a set of Big Block Chevrolet intake and exhaust valves from Ferrea.
Additional Considerations For Optimal Valve Performance
Finding performance in valves typically comes from a couple of different factors. The first, as with virtually any internal component, is weight. For example, hollow stem valves, which have been on the market for several years now, have proven to offer a great deal of increased performance due to their lighter weight. The second factor comes in the form of multiple enhancements, such as undercut stems and altered profiles that correspond to the particular port design of the cylinder head. In addition to automotive valves and valvetrain components, Ferrea produces or has played a role in the design of poppet valves for natural gas engines, tank valves, the aviation industry, oil pump engines, unmanned vehicle for the miliatry, and virtually any other type of internal combustion engine that uses valves.
Custom Valve Ordering
In addition to their wide and varying selection of valves, Ferrea can produce a custom set of valves for your application and per your specifications, so long as the desired valve conforms to the parameters of the blanks valves off the shelf. “We can custom make just about any valve, on any stem size relative to what we have available,” says Urrutia. “Today, we can make valves with 4mm stems up to 3/8-inch, and we can usually get them done within a two week span. We also do short production runs on any valve that we have readily available as a blank form.”