Kevin can post or not, that's his perogotive. But to answer your question about whether other tuners (Doug L., Jason H., Sean Roe, John H.) post, YES, they do. Primarily on .org, John H. on the Alley. Do they give away trade secrets. Probably not. Do they answer 99% of the questions thrown at them - Yes, from what I've seen.
Personally, I just like to hear answers from a technical perspective. Sometimes these answers can help with my application, albiet different. I actually have no interest in a centrifugal type blower, as I personally feel it turns the Viper into more of a 'straight line car', and much less of a 'road race car'. I've found they are challenging to control (ie - wheelspin) on the straights, let alone powering out of a corning. The Centrifugal Viper I test drove was 750 RWHP. Don't get me wrong, it was fun, sounded great, and scared small children and animals. But trying to power out of corners became a heart stopping experience.
Kevin can post or not, that's his perogotive. But to answer your question about whether other tuners (Doug L., Jason H., Sean Roe, John H.) post, YES, they do. Primarily on .org, John H. on the Alley. Do they give away trade secrets. Probably not. Do they answer 99% of the questions thrown at them - Yes, from what I've seen.
Personally, I just like to hear answers from a technical perspective. Sometimes these answers can help with my application, albiet different. I actually have no interest in a centrifugal type blower, as I personally feel it turns the Viper into more of a 'straight line car', and much less of a 'road race car'. I've found they are challenging to control (ie - wheelspin) on the straights, let alone powering out of a corning. The Centrifugal Viper I test drove was 750 RWHP. Don't get me wrong, it was fun, sounded great, and scared small children and animals. But trying to power out of corners became a heart stopping experience.
Not doing any road racing anytime soon. LOL I told Kevin to come on if he wanted. I am not his mother so don't blame me if he chooses not to.
Paolo, what kind of hp increase is normally seen per pound of boost. I know Treynor has put out some equation to determine or speculate what kind of output a car would have at certain boost levels.
Someone previously said this car would be around 33 hp/lb if the car started with 480 hp.
John
John, the way to calculate the theoretical maximum increase in horsepower is the following: PSI+ 14.7 PSI/ 14.7 PSI = multiplication factor of stock horsepower ASSUMING 100% EFFICIENCY ie no heating up of the air charge, no parasitic power loss to drive the supercharger off the crank/etc......
Another thing to consider here is the fact that there is a decreasing marginal return for each additional # of boost. In simple terms, the 1st # of boost gains you the most with each additional PSI yielding marginally less RWHP than the the one before it.
So any calculation of total RWHP gained divided by the # of PSI is an AVERAGE gain of RWHP/PSI.
Here is a simple example:
@ 14.7 PSI, you would have 14.7 + 14.7/ 14.7 = 29.4/14.7 = 2
In simple terms, this is 2 times the original power output of the engine.
In the real world, this never happens in a supercharged application.( There are certain turbocharged applications where you can actually make MORE than the theoretical maximum)
The most RWHP I have ever seen on a stock engine with cat back is around 440 RWHP.
This 885 RWHP minus 440 RWHP would be a gain of 445 RWHP. (Slightly more than double the power)
Some #'s I can quote for sure would be those of my car.
My car made 500 RWHP and 504 RWTQ in the N/A mode wih 8.5:1 compression.
at 13.5 PSI with {the intake manifold cut in 1/2, polished and ported and welded back together==>added after the initial N/A dyno pulls}, heads, cam, 1.7 T&D roller rockers, being bored .010 over, fuel system to supply the power, 1.75" headers/no cats/side exhaust, and a very large and efficient air-air intercooler, my car made 887.7 RWHP and 864.5 RWTQ.
So 13.5 + 14.7/14.7 = 1.9183673 (theoretical) multiplication factor
Hypothetically, I should have made 1.9183673(500 RWHP) or 959.18 THEORETICAL RWHP and 1.9183673(504 RWTQ) or 966.85 THEORETICAL RWTQ
My car made 887.7 RWHP or 887.7/959.18 which is 92.55% of the theoretical maximum for HP==> This equates to a 7.45% loss in efficiency.
My car made 864.5 RWTQ or 864.5/966.85 which is 89.41% of the theoretical maximum for RWTQ==> This equates to a 10.59% loss in efficiency(Some power to drive the supercharger I would imagine)
{I also just realized I added the intake after the initial 500 RWHP/504 RWTQ so my efficiency might be a tad lower than the #'s I have just listed}
Now back to the matter at hand
Even if '96 GTS's car made 440 RWHP with the stock headers and cat back, the theoretical maximum for RWHP would be 13 + 14.7/ 14.7 = 1.8843537 multiplication factor
So 1.884357 x 440 RWHP = 829 theoretical RWHP
let's say 480 RWTQ
So 480 x 1.884357 = 904 theoretical RWTQ
'96 GTS made 6.75% more than the theoretical maximum for RWHP and 5.973% less than the theoretical maximum for RWTQ.
'96 GTS's car made 34.23 average RWHP/PSI and 28.42 average RWTQ/PSI.
My car only made 28.72 average RWHP/PSI and 26.7 average RWTQ/PSI.
To put this into perspective I believe Smokin V-10 with stock compression, stock heads, 1.7 T&D's, headers/no cats made somewhere around 775 RWHP and 765 RWTQ on 13 PSI. I think his car made somewhere around 460 RWHP and 510 RWTQ in the N/A mode. I could be slightly off on his #'s but the point is clear:
Another thing to consider here is that the pulley that made 13 PSI on Smokin's car made only 10 PSI on my car.
This means that the headwork and cam on my car make for a larger volume to be filled with the SAME CFM of air from the same blower, crank pulley and supercharger pulley==> So when I have 13.5 PSI, I am surely flowing more air than Smokin at his 13 PSI.
The moral of the story here is that the headwork and certain other modifications INCREASE the volumetric efficiency of the motor.
So stock heads, cam, exhaust manifolds/etc..... are obviously LESS volumetrically efficient than heads that have been polished, ported and have bigger valves, bigger cam, 1.75" primary tube headers/no cats etc.....
I made 4.49 more RWHP/PSI and 7.08 more RWTQ/PSI than Smokin(We both have 1.7 roller rockers)
Now '96 GTS makes 5.51 MORE RWHP and 1.72 MORE RWTQ than me with everything being BONE STOCK is just a little hard to believe.
If I am off base here, somebody please tell me where I am missing the point.
P.S. '96 GTS: I am not trying to be a prick here, I just do not understand how these #'s are possible in the context of what I know about the physical laws of forced induction.
HEY PAOLO - DID YOU EVER SEE "MONTY PYTHON'S HOLY GRAIL"? THERE IS A SCENE WHERE THE MOB SAYS, "SHE'S A WITCH, BURN HER!" AT WHICH POINT SOMEBODY ASKS THE QUESTION, "HOW DO YOU KNOW SHE'S A WITCH?"
AND SOME GUY PROCEDES TO ANSWER THE QUESTION USING A LOT OF INTERESTING COMPARISONS TO REACH HIS CONCLUSION. IF YOU HAVE NOT SEEN THIS SCENE OR THIS MOVIE, YOU REALLY SHOULD RENT IT, ITS HILLARIOUS!
HEY PAOLO - DID YOU EVER SEE "MONTY PYTHON'S HOLY GRAIL"? THERE IS A SCENE WHERE THE MOB SAYS, "SHE'S A WITCH, BURN HER!" AT WHICH POINT SOMEBODY ASKS THE QUESTION, "HOW DO YOU KNOW SHE'S A WITCH?"
AND SOME GUY PROCEDES TO ANSWER THE QUESTION USING A LOT OF INTERESTING COMPARISONS TO REACH HIS CONCLUSION. IF YOU HAVE NOT SEEN THIS SCENE OR THIS MOVIE, YOU REALLY SHOULD RENT IT, ITS HILLARIOUS!
HAVE A GREAT THANKSGIVING. [/quote]
John,
"My best friend's sister's boyfriend's brother's girlfriend heard from this guy who knows this kid who's going with the girl who saw Ferris pass out at 31 Flavors last night....... I guess it's pretty serious....."
I know the scene in Monty Python's Holy Grail, That is funny!
how do you deal with the heads lifting under boost?
what about your crank and damper? Are they upgraded or keyed? I've personally seen a viper's damper snap off from being supercharged (crank is directly turning the s/c) and that was only with about 600HP. Over time , these things will happen. I hope you've taken all the precautionary steps and I hope anyone that uses your friend insists on these things done or the life of their motor will be dramatically comprimised...
Paolo's post re theoretical maximums etc is not "being a prick" - he is simply stating long established fact re boosting engines.
That does not mean that the engine did not make 885rwhp on the dyno - I'm sure it did. It would be interesting if it made the same on another dyno when corrected - but assuming it did the fact is that Kevin has improved that engine beyond stock more than just adding a blower... a lot more.
The base engine is making at least 570hp at crank and 490rwhp. The real question is how did a stock engine do that? It is highly likely that the basic car has had a cam and heads job in a previous life.
It is impossible for 13lb boost to add over 100% power at wheels on 13lb boost on a supercharger - it is physically impossible.
I'm not calling BS - because the graph is awesome and when the car runs some times the trap speed will indicate a lot - but I am pointing out that the questions arise from valid confusion trying to understand how 13lb of boost did it without defying the known laws.... I'm convinced that if you ran zero boost - you'd have close to 500rwhp and that is way more than any stock V10.
So it sounds like you got a good base modified engine GTS! Nothing wrong with a pleasant surprise getting more than you thought - that is cool - but someone hasn't told you everything that is for sure.
Paolo's post re theoretical maximums etc is not "being a prick" - he is simply stating long established fact re boosting engines.
That does not mean that the engine did not make 885rwhp on the dyno - I'm sure it did. It would be interesting if it made the same on another dyno when corrected - but assuming it did the fact is that Kevin has improved that engine beyond stock more than just adding a blower... a lot more.
The base engine is making at least 570hp at crank and 490rwhp. The real question is how did a stock engine do that? It is highly likely that the basic car has had a cam and heads job in a previous life.
It is impossible for 13lb boost to add over 100% power at wheels on 13lb boost on a supercharger - it is physically impossible.
I'm not calling BS - because the graph is awesome and when the car runs some times the trap speed will indicate a lot - but I am pointing out that the questions arise from valid confusion trying to understand how 13lb of boost did it without defying the known laws.... I'm convinced that if you ran zero boost - you'd have close to 500rwhp and that is way more than any stock V10.
So it sounds like you got a good base modified engine GTS! Nothing wrong with a pleasant surprise getting more than you thought - that is cool - but someone hasn't told you everything that is for sure.
This is getting quite interesting! I love reading Torque's emails -- the guy seems like an Einstein on engines for some reason, at least from what I read.
The base engine is making at least 570hp at crank and 490rwhp. The real question is how did a stock engine do that? It is highly likely that the basic car has had a cam and heads job in a previous life.
It is impossible for 13lb boost to add over 100% power at wheels on 13lb boost on a supercharger - it is physically impossible.
Torquemaster, the video of his Dyno shows the stock power being 412 RWHP, FYI.
Torquemaster, the video of his Dyno shows the stock power being 412 RWHP, FYI.
BURRRRPP!!
Pardon me
Definitely not Einstein Superbar.
412rwhp - that's interesting and that is reasonable for a stock engine. That kills the head and cam idea.... [img]/images/graemlins/laughing.gif[/img]
13lb boost would get it to 775rwhp if twin turbo'd but blower losses would drop that to around 755rwhp. That means there is something else helping to make up the other 130rwhp - and it's more than just timing because 412rwhp would have been achieved on full power n/a timing and the boost power calculation assumes no retard at full boost to get 775rwhp.
Unless someone fed in some magic mushrooms there's more here than some mystical magic that is for sure. I don't believe in magic
I think it's the boost number that's off. I can believe everything else about this scenario but that. I think RSI950 posted a page or so back that his Paxton setup produced 13 psi with a larger pulley than what Matt is running, and I think Matt also said in a previous post that he was getting 12 psi at around 4,800-5,000 rpm when they were first getting started (and we all know centrifugals build boost in a linear fashion). So 16-17 psi would jive with those comments and also would explain the peak numbers. What do you say Torque?
I think it's the boost number that's off. I can believe everything else about this scenario but that. I think RSI950 posted a page or so back that his Paxton setup produced 13 psi with a larger pulley than what Matt is running, and I think Matt also said in a previous post that he was getting 12 psi at around 4,800-5,000 rpm when they were first getting started (and we all know centrifugals build boost in a linear fashion). So 16-17 psi would jive with those comments and also would explain the peak numbers. What do you say Torque?
yeah 2 Vipairs might do it [img]/images/graemlins/freak[/img]
Red - to get 885rwhp from 412rwhp would take 18.5lb boost MINIMUM on a blower and even then it assumes the intercooler is efficient enough to allow full power timing advance.... To get that power from 17lb allows no losses at all - only realistic with TT not driving a pump.
Remember the higher the boost the more heat, therefore the efficiency of the intercooler tapers off at a certain point.
If Kevin would come on and explains how he added 130rwhp the mystery would be solved - I think it comes down to either an extra power adder or a break-thru in known automotive technology that is unknown to anyone else.
Ok I called Kevin to find out where this mysterious HP is coming from, and after a 30 minute chat, I got the low down. Believe it, the HP is true. He has figured something out that nobody else has, and for less than $50 (yes, FIFTY dollars), we can all add over 150 HP to our cars. For less than $10K, we can all have near 900 RWHP cars!!! So this is where this 135 or 140 HP discrepency is coming from. We are all thinking it is coming from just boost, but that is not the case. But fr $50, who cares where it comes from.
He had to explain it twice to me for it to sink in, and then I had to verify it with one of my tuner buddies, and we were all blown away with how this 150 HP is pulled out of the engine, safely. We couldn't believe how easy (yet complicated to think up) it was. It's truly AMAZING! And after a full explanation, there is absolutely never, ever going to be an issue with detonation, even with 89 octane gas. He uses some really wild tricks. The crank strength is something he is working on and has a quick and inexpensive fix that I have never seen another tuner do, as well. I gotta go sit down... head spinning. Pulling out wallet.
HEY PAOLO - DID YOU EVER SEE "MONTY PYTHON'S HOLY GRAIL"? THERE IS A SCENE WHERE THE MOB SAYS, "SHE'S A WITCH, BURN HER!" AT WHICH POINT SOMEBODY ASKS THE QUESTION, "HOW DO YOU KNOW SHE'S A WITCH?"
AND SOME GUY PROCEDES TO ANSWER THE QUESTION USING A LOT OF INTERESTING COMPARISONS TO REACH HIS CONCLUSION. IF YOU HAVE NOT SEEN THIS SCENE OR THIS MOVIE, YOU REALLY SHOULD RENT IT, ITS HILLARIOUS!
HAVE A GREAT THANKSGIVING.
John,
"My best friend's sister's boyfriend's brother's girlfriend heard from this guy who knows this kid who's going with the girl who saw Ferris pass out at 31 Flavors last night....... I guess it's pretty serious....."
I know the scene in Monty Python's Holy Grail, That is funny!
[/quote]Not sure wha the fuck you are implying b/c I am a slow redneck. However if you are implying that anything I have posted is not the truth it all can be backed up. My sisters cousins b/f told me that you would cry the most on here. LOL
how do you deal with the heads lifting under boost?
what about your crank and damper? Are they upgraded or keyed? I've personally seen a viper's damper snap off from being supercharged (crank is directly turning the s/c) and that was only with about 600HP. Over time , these things will happen. I hope you've taken all the precautionary steps and I hope anyone that uses your friend insists on these things done or the life of their motor will be dramatically comprimised...
Gerald
Yes both are custom done and very nice I must say. The dampner is one hell of piece of work. I have never seen anything like it.
