Fun w/ Numbers - Supercharger vs. V8
04-01-2009, 07:33 PM
#23
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Join Date: Aug 2006
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Your numbers are wrong. I edited my post. I was pushing 16lbs of boost, 75 shot, on a fully built block, though I had stock rods. It didn't hold together.
Not to mention unless you have an engine dyno, crank numbers don't mean squat. Thats why no one uses them except for car salesmen. The math is never accurate once you start modding a car.
Not to mention unless you have an engine dyno, crank numbers don't mean squat. Thats why no one uses them except for car salesmen. The math is never accurate once you start modding a car.
the 500 hp Turbo car is Fazm's car.
the 465 hp car is a blue full exhaust vortech car with cams and heads that I've seen in person.
Also the math is accurate the Mustang has very consistently across all it's applications shown that it has a 15% drivetrain loss with very little variation. This has been proven by engine builders and magazines simultaneously, with setups ranging from Saleen, to prototype shop cars with hundreds of mods to stock cars (v6 gt500 and v8 were tested).
The 1200 hp v6 involves an engine swap which is better with a v6 due to the lower price.
Last edited by Legion5; 04-01-2009 at 07:42 PM.
04-01-2009, 07:51 PM
#25
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Join Date: Jul 2005
Posts: 5,172
I don't know what to say other than I'm not wrong.
the 500 hp Turbo car is Fazm's car.
the 465 hp car is a blue full exhaust vortech car with cams and heads that I've seen in person.
Also the math is accurate the Mustang has very consistently across all it's applications shown that it has a 15% drivetrain loss with very little variation. This has been proven by engine builders and magazines simultaneously, with setups ranging from Saleen, to prototype shop cars with hundreds of mods to stock cars (v6 gt500 and v8 were tested).
The 1200 hp v6 involves an engine swap which is better with a v6 due to the lower price.
the 500 hp Turbo car is Fazm's car.
the 465 hp car is a blue full exhaust vortech car with cams and heads that I've seen in person.
Also the math is accurate the Mustang has very consistently across all it's applications shown that it has a 15% drivetrain loss with very little variation. This has been proven by engine builders and magazines simultaneously, with setups ranging from Saleen, to prototype shop cars with hundreds of mods to stock cars (v6 gt500 and v8 were tested).
The 1200 hp v6 involves an engine swap which is better with a v6 due to the lower price.
My concern here is you post crank numbers which muddy the waters for people buying kits, and looking at dyno sheets advertised at rwhp.
04-01-2009, 07:52 PM
#26
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Join Date: Jul 2005
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Again, I'm not debating crank numbers because they don't apply to our hobby. Who builds a car with crank numbers, no one. Again, like I said before, your crank HP posts don't help people using these cars in real racing applications. No performance shop uses crank numbers, they use ETs and dynos that are SAE corrected at the rear wheels.
04-01-2009, 08:02 PM
#27
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Join Date: Feb 2006
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legion some of us know each other very well and even talk personally. Your numbers are off and misleading to the OP. So lets not start a bench racing/dyno # he said/she said debate.
@ OP what are your goals for your car and your budget? From real world info gathered from the owners themselves and actually watching most of the aforementioned cars run here is some basic info. The s197 is a great chassis and both motors are very nice. Now the 4.0 block itself is supposed to be good to around 500 rwhp (matching the venerable stock 5.0 block). So that is the ceiling for 4.0 performance which is much higher than most would ever go. Now on stock block we have seen centuris crack high 11s on higher boost (don't quote but I think 12-14 psi), X charger in the hands of a good racer will hit lower 13s with supporting mods and 2.8 pulley (that number maybe slightly off as well), the PH turbo will hit low 12s maybe crack a 11.9x on 11 psi. The PH turbo with a 75 sot has craked 10s and blocks. Lots of cool options.
The 3v stock motor should be good to around 475-500 rwhp. The stock pistons and rods are not boost friendly. With stock internals they can handle ALOT of power (those levels are also debated). A full bolt on GT stock motor have hiy high 11s but the norm is low 12s. Cammed, LT cars are hitting upper 11s maybe a mid 11. FI 3vs are all over depending on driver and the setup. Good luck on your purchase. If you are looking for a fun street car either engine is more than enough. If you are looking for 500 rwhp or more I say go 3 valve.
@ OP what are your goals for your car and your budget? From real world info gathered from the owners themselves and actually watching most of the aforementioned cars run here is some basic info. The s197 is a great chassis and both motors are very nice. Now the 4.0 block itself is supposed to be good to around 500 rwhp (matching the venerable stock 5.0 block). So that is the ceiling for 4.0 performance which is much higher than most would ever go. Now on stock block we have seen centuris crack high 11s on higher boost (don't quote but I think 12-14 psi), X charger in the hands of a good racer will hit lower 13s with supporting mods and 2.8 pulley (that number maybe slightly off as well), the PH turbo will hit low 12s maybe crack a 11.9x on 11 psi. The PH turbo with a 75 sot has craked 10s and blocks. Lots of cool options.
The 3v stock motor should be good to around 475-500 rwhp. The stock pistons and rods are not boost friendly. With stock internals they can handle ALOT of power (those levels are also debated). A full bolt on GT stock motor have hiy high 11s but the norm is low 12s. Cammed, LT cars are hitting upper 11s maybe a mid 11. FI 3vs are all over depending on driver and the setup. Good luck on your purchase. If you are looking for a fun street car either engine is more than enough. If you are looking for 500 rwhp or more I say go 3 valve.
Last edited by firestang70; 04-01-2009 at 08:05 PM.
04-01-2009, 08:23 PM
#29
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Join Date: Aug 2006
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A lot of tuners commonly believe that dyno conversion is inaccurate, which it is but the mustang is understood by some tuners and seems a big exception to the rule. I've only talked to two top tuners and read two magazine articles which all said the same thing based on testing, but are you sure that the top tuners aren't just using general dyno information instead of actual numbers? very few people outside engine builders use crank dynos which is what we run in top level SCCA racing exclusivly.
Racing is part of the reason I'm familiar with crank numbers and the other is that everyone who buys Saleen stuff seems to use them too. "435 hp kit" "475 hp kit" "500 hp JDM kit" "better than the 500 hp GT500" etc.
Numbers like 11s 12s 10s are as confusing as crank numbers because they are chassis and driver dependent, but I would say that crank numbers are less useful in the v6 because nobody needs to compare them to stock kits from popular manufacturers because v6s have their largest following in homebrew style mods that all mash together. That's the main reason, comparing manufacturer numbers, people with GT's even need to use them, it's an important reason but you don't see it here.
Anyways I can definitely say that you are wayy off in your numbers for the v8 (ironically i bet there is a paralell here). The v8 will blow in about 20%-30% of cars according to two top tuners at 500 crank hp without any bolt ons. While it can hit 475 RWHP that's a best case scenario longshot. 500 RWHP will blow a 3v engine consistently.
Racing is part of the reason I'm familiar with crank numbers and the other is that everyone who buys Saleen stuff seems to use them too. "435 hp kit" "475 hp kit" "500 hp JDM kit" "better than the 500 hp GT500" etc.
Numbers like 11s 12s 10s are as confusing as crank numbers because they are chassis and driver dependent, but I would say that crank numbers are less useful in the v6 because nobody needs to compare them to stock kits from popular manufacturers because v6s have their largest following in homebrew style mods that all mash together. That's the main reason, comparing manufacturer numbers, people with GT's even need to use them, it's an important reason but you don't see it here.
Anyways I can definitely say that you are wayy off in your numbers for the v8 (ironically i bet there is a paralell here). The v8 will blow in about 20%-30% of cars according to two top tuners at 500 crank hp without any bolt ons. While it can hit 475 RWHP that's a best case scenario longshot. 500 RWHP will blow a 3v engine consistently.
Last edited by Legion5; 04-01-2009 at 10:39 PM.
04-01-2009, 08:24 PM
#30
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Join Date: Jul 2005
Posts: 5,172
I'll give a perfect example why the crank calculation is not applicable. A car dynos at 500 rwhp on a DJ. The same car dynos at 560 on a properly loaded and calibrated Mustang Dyno at 560. So, which one do you apply the 15% to (assuming its a auto), or 20% (assuming its a manual).
Not to mention that auto transmissions see different drive train loss depending on the type of trans, converter and other components. Some people say for S197's, 12% should be applied to manuals and 19% should be applied to automatics. There are other factors that come into play, gearing, rotating mass...even wheel/tire size.
Even rwhp dyno numbers are not 100%. All of this is guestimates. Here is a very good recent thread on the new E-Force blower dyno results, that goes into the ins and outs of dyno numbers:
http://s197forum.com/forum/showthrea...t=14279&page=2
Not to mention that auto transmissions see different drive train loss depending on the type of trans, converter and other components. Some people say for S197's, 12% should be applied to manuals and 19% should be applied to automatics. There are other factors that come into play, gearing, rotating mass...even wheel/tire size.
Even rwhp dyno numbers are not 100%. All of this is guestimates. Here is a very good recent thread on the new E-Force blower dyno results, that goes into the ins and outs of dyno numbers:
http://s197forum.com/forum/showthrea...t=14279&page=2