S/C psi vs rwhp poll
01-21-2008, 04:06 PM
#12
Join Date: Aug 2007
Location: Jacksonville, FL
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RE: S/C psi vs rwhp poll
510rwhp at 10psi would be very hard, I an running 10psi with intercooler with almost every bolt on you can do,and i pulled off 486, for me to make that I would need a cam and a port and polish and i would stilll probaly fall short. I would vote the first one 450whp at 10psi not 12.
01-21-2008, 04:08 PM
#13
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RE: S/C psi vs rwhp poll
i didn't vote both ways, but i did vote
i'll be interested to see more on this later...
i'll be interested to see more on this later...
ORIGINAL: TJ
That will be CT hope the guys who voted both ways will chime in.
hammeron ?
ORIGINAL: hammeron
is that EST or PST
is that EST or PST
hammeron ?
01-21-2008, 04:10 PM
#14
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RE: S/C psi vs rwhp poll
ORIGINAL: LX200
You can't make 510 HP at 10 psi..... 24.7 psi (boost) / 14.7 psi (atmospheric) = 1.68 times more air IF YOU COULD INTERCOOL it back to ambient temp (which you can't) which gives you 270 HP (stock GT) times 1.68 = 453 HP. I don't see how it's possible to extract 60 more HP above this without putting in the air to combust....
You can't make 510 HP at 10 psi..... 24.7 psi (boost) / 14.7 psi (atmospheric) = 1.68 times more air IF YOU COULD INTERCOOL it back to ambient temp (which you can't) which gives you 270 HP (stock GT) times 1.68 = 453 HP. I don't see how it's possible to extract 60 more HP above this without putting in the air to combust....
http://youtube.com/watch?v=fT3PQoVQ0zI
There have been other guys dyno at 465-474rwhp on a stock motor (mygt500 member hereis at 465rwhpand left power on the table) at 10 psi on a Whipple add heads (around 40rwhp alone)and cams and your therearound 510rwhp
The original question/poll was just saying if these were the only two setups to choose for a reason.
01-21-2008, 04:26 PM
#15
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RE: S/C psi vs rwhp poll
ORIGINAL: hammeron
i didn't vote both ways, but i did vote
i'll be interested to see more on this later...
i didn't vote both ways, but i did vote
i'll be interested to see more on this later...
ORIGINAL: TJ
That will be CT hope the guys who voted both ways will chime in.
hammeron ?
ORIGINAL: hammeron
is that EST or PST
is that EST or PST
hammeron ?
01-21-2008, 05:13 PM
#17
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RE: S/C psi vs rwhp poll
I guess you guys will never learn the lesson that dynos don't mean squat....lol
Understand that you can increase timing in the tune and get loads of HP. Run some C16 and give 10 psi 38ยบ and you'll make 500. Because it doesn't blow up on the dyno - does that mean it's safe? Hell no.
When I had my vortech, the difference between my street tune and my race tune was a whopping 90 rwhp. No changes in anything other than the tune with a lot more timing and race gas. Timing = HP - plain and simple.
I could drop a manual in my car now and for giggles probably turn a 1000 rwhp number on the dyno if I tired hard enough but for what purpose? My favorite time was when my car was running low 10's and showing on the dyno 540 rwhp...lol[8D]
Poll all you want and debate all you want. The reality will not change that 10 psi on a TS or TC and 12 psi on a centrifugal is a heavy enough burden on your stock rods and just a 'matter of time' with any more...
Understand that you can increase timing in the tune and get loads of HP. Run some C16 and give 10 psi 38ยบ and you'll make 500. Because it doesn't blow up on the dyno - does that mean it's safe? Hell no.
When I had my vortech, the difference between my street tune and my race tune was a whopping 90 rwhp. No changes in anything other than the tune with a lot more timing and race gas. Timing = HP - plain and simple.
I could drop a manual in my car now and for giggles probably turn a 1000 rwhp number on the dyno if I tired hard enough but for what purpose? My favorite time was when my car was running low 10's and showing on the dyno 540 rwhp...lol[8D]
Poll all you want and debate all you want. The reality will not change that 10 psi on a TS or TC and 12 psi on a centrifugal is a heavy enough burden on your stock rods and just a 'matter of time' with any more...
01-21-2008, 06:05 PM
#18
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RE: S/C psi vs rwhp poll
First the disclaimer this is just my understanding and my belief.
The poll was only to see where most people believe what is more critical an adverse effect on a stock S197 motor psi or power/rwhp& rwtq. The two setups & poll were listed by design to single out psi or power rwh/rwtq. They were not intended to say you could get 510rwhp (or to run safely) or should try they were just examples used for this poll per above reason.
IMO opinion the more safersetup to run is the 450rwhp/430rwtq @ 12psi in this poll.
The reason why imo
The 510rwhp/480rwtq @10psi is at higher risk of blowing imo due to this level of power you are making on this motor. Each cylinder (pistons & rods) has more pressure on it and has to produce more power at this level.
The safer setup is the 450rwhp/430rwtq @ 12psi this setup will put the motor at less risk than the above setup, running a 2 psi higher is less pressure on the pistonโs, rods than running 510rwhp/480rwtq @10psi.
The guys who voted for 450rwhp/430rwtq @ 12psi give your opinions of why you feel this is the safer setup and or if you also agree on the above, be interested imo to see who voted this way also.
Ok you guys who voted for 510rwhp/480rwtq @10psi if you could give your opinions on why you voted this is a safer setup.
I am always willing to learn.
Ok could we get full disclosure of who voted and what you voted for.
Once again all of the above just my opinion and belief.
The poll was only to see where most people believe what is more critical an adverse effect on a stock S197 motor psi or power/rwhp& rwtq. The two setups & poll were listed by design to single out psi or power rwh/rwtq. They were not intended to say you could get 510rwhp (or to run safely) or should try they were just examples used for this poll per above reason.
IMO opinion the more safersetup to run is the 450rwhp/430rwtq @ 12psi in this poll.
The reason why imo
The 510rwhp/480rwtq @10psi is at higher risk of blowing imo due to this level of power you are making on this motor. Each cylinder (pistons & rods) has more pressure on it and has to produce more power at this level.
The safer setup is the 450rwhp/430rwtq @ 12psi this setup will put the motor at less risk than the above setup, running a 2 psi higher is less pressure on the pistonโs, rods than running 510rwhp/480rwtq @10psi.
The guys who voted for 450rwhp/430rwtq @ 12psi give your opinions of why you feel this is the safer setup and or if you also agree on the above, be interested imo to see who voted this way also.
Ok you guys who voted for 510rwhp/480rwtq @10psi if you could give your opinions on why you voted this is a safer setup.
I am always willing to learn.
Ok could we get full disclosure of who voted and what you voted for.
Once again all of the above just my opinion and belief.
01-21-2008, 06:29 PM
#19
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RE: S/C psi vs rwhp poll
You also should determine if these two examples are on a twin screws or whatever...? (yes - it DOES make a difference)
On a centrifugal - my vote would be for the 12 psi option
On a TS - my vote would be for the 10 psi option.
Totally different scenarios and max boost under load, etc. etc.
A good rule of thumb is what I said above in my last post and have a professional tuner dial it in safely. When you see these toothbrush rods in your stock motor, you will understand there is no reason to try to push them. Especially since if you put out the big dollars for a blower, why not just upgrade your internals and not worry about it at all?
If we are talking about twins screws here, then the 12 psi is certainly not safer than the 10 psi with good gas and a good tune making that kind of power. Your TUNE dictates HP even more so than your psi. How cold I possibly say which is safer unless I knew exactly what the tune parameters and the octane used to get the hp number on your 10 psi example?
I understand what you are trying to do but it is not that simple. There are way too many factors (within the tune) to consider before you could actually determine which was 'safer'. The one fact that you can't ignore and what I base my opinion on is the amount of boost and given both tunes are in acceptable a/f, mass air transfer functions, spark advance, octane, etc, etc - then the 12 psi is certainly going to be harder on your rods.
What if I was making 496 rwhp with 10 psi on VP109 octane with 26ยบ peak timing, and my a/f at a solid 11.9 and pulling the car to 6200?
NOW...
What if I was making 440 rwhp with 10 psi on 91 pump gas with 22ยบ of timing and my a/f at 12.9 and pulling the car to 6800?
Guess what? - the 496 rwhp tune is safer on my motor than the 440 rwhp tune!
Just an example to illustrate it is not as simple as rwhp vs. boost - there is far more to it than that. If it was that easy, we'd all be tuning our own cars...
On a centrifugal - my vote would be for the 12 psi option
On a TS - my vote would be for the 10 psi option.
Totally different scenarios and max boost under load, etc. etc.
A good rule of thumb is what I said above in my last post and have a professional tuner dial it in safely. When you see these toothbrush rods in your stock motor, you will understand there is no reason to try to push them. Especially since if you put out the big dollars for a blower, why not just upgrade your internals and not worry about it at all?
If we are talking about twins screws here, then the 12 psi is certainly not safer than the 10 psi with good gas and a good tune making that kind of power. Your TUNE dictates HP even more so than your psi. How cold I possibly say which is safer unless I knew exactly what the tune parameters and the octane used to get the hp number on your 10 psi example?
I understand what you are trying to do but it is not that simple. There are way too many factors (within the tune) to consider before you could actually determine which was 'safer'. The one fact that you can't ignore and what I base my opinion on is the amount of boost and given both tunes are in acceptable a/f, mass air transfer functions, spark advance, octane, etc, etc - then the 12 psi is certainly going to be harder on your rods.
What if I was making 496 rwhp with 10 psi on VP109 octane with 26ยบ peak timing, and my a/f at a solid 11.9 and pulling the car to 6200?
NOW...
What if I was making 440 rwhp with 10 psi on 91 pump gas with 22ยบ of timing and my a/f at 12.9 and pulling the car to 6800?
Guess what? - the 496 rwhp tune is safer on my motor than the 440 rwhp tune!
Just an example to illustrate it is not as simple as rwhp vs. boost - there is far more to it than that. If it was that easy, we'd all be tuning our own cars...
01-21-2008, 07:07 PM
#20
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Join Date: Sep 2005
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RE: S/C psi vs rwhp poll
ORIGINAL: modaddict
You also should determine if these two examples are on a twin screws or whatever...? (yes - it DOES make a difference)
On a centrifugal - my vote would be for the 12 psi option
On a TS - my vote would be for the 10 psi option.
Totally different scenarios and max boost under load, etc. etc.
You also should determine if these two examples are on a twin screws or whatever...? (yes - it DOES make a difference)
On a centrifugal - my vote would be for the 12 psi option
On a TS - my vote would be for the 10 psi option.
Totally different scenarios and max boost under load, etc. etc.
Could you give a reason why you believe this?
Ok so on a centri you agree.
Mark I do agree will a lot ofof what you postin the past regarding these cars but this isone areaI have disagree.
A good rule of thumb is what I said above in my last post and have a professional tuner dial it in safely. When you see these toothbrush rods in your stock motor, you will understand there is no reason to try to push them. Especially since if you put out the big dollars for a blower, why not just upgrade your internals and not worry about it at all?
If we are talking about twins screws here, then the 12 psi is certainly not safer than the 10 psi with good gas and a good tune making that kind of power. Your TUNE dictates HP even more so than your psi. How cold I possibly say which is safer unless I knew exactly what the tune parameters and the octane used to get the hp number on your 10 psi example?
I understand what you are trying to do but it is not that simple. There are way too many factors (within the tune) to consider before you could actually determine which was 'safer'. The one fact that you can't ignore and what I base my opinion on is the amount of boost and given both tunes are in acceptable a/f, mass air transfer functions, spark advance, octane, etc, etc - then the 12 psi is certainly going to be harder on your rods.
What if I was making 496 rwhp with 10 psi on VP109 octane with 26ยบ peak timing, and my a/f at a solid 11.9 and pulling the car to 6200?
NOW...
What if I was making 440 rwhp with 10 psi on 91 pump gas with 22ยบ of timing and my a/f at 12.9 and pulling the car to 6800?
Guess what? - the 496 rwhp tune is safer on my motor than the 440 rwhp tune!
Just an example to illustrate it is not as simple as rwhp vs. boost - there is far more to it than that. If it was that easy, we'd all be tuning our own cars...