question about psi and hp
Thread Starter
single digit dreamer
iTrader: (6)
Joined: Mar 2002
Posts: 9,757
Likes: 4
From: omaha ne
question about psi and hp my question relates to the recent dyno numbers from the qmp kit. i am in no way doubting that they got 750rwhp. i am not trying to start anything, just trying to understand a few things.
from what i understand a stock 98 6sp ls1 dynos around 300rwhp
from what i understand you will double your hp for every 14.7psi of boost, that is in a perfect word where you can completely cool the air back down to ambiant and there is no restriction in the exhaust from the turbo.
with those numbers that would put a stock 98ls1 at 14.7psi around 600rwhp or less.
clearly i am missing something and like i said i am not questioning the dyno numbers, just want to know what part of the equasion i am missing.
from what i understand a stock 98 6sp ls1 dynos around 300rwhp
from what i understand you will double your hp for every 14.7psi of boost, that is in a perfect word where you can completely cool the air back down to ambiant and there is no restriction in the exhaust from the turbo.
with those numbers that would put a stock 98ls1 at 14.7psi around 600rwhp or less.
clearly i am missing something and like i said i am not questioning the dyno numbers, just want to know what part of the equasion i am missing.
Thread Starter
single digit dreamer
iTrader: (6)
Joined: Mar 2002
Posts: 9,757
Likes: 4
From: omaha ne
Originally Posted by Pro Stock John
Rob has a big turbo on his car, he's running a lot of methanol to act like high octane gas (ie. like C16), and he's probably running a lot of timing.
TECH Enthusiast
Joined: Nov 2003
Posts: 689
Likes: 0
Originally Posted by parish8
i understand that. i would think that these things would get him closer to actualy doubling his hp but still not more than double. if he could cool the charge to colder than ambiant or if he was over 14.7psi then i could understand over double the hp.
Thread Starter
single digit dreamer
iTrader: (6)
Joined: Mar 2002
Posts: 9,757
Likes: 4
From: omaha ne
Originally Posted by unit213
The track will tell the tale with this car.
BUT
i think the stuff you guys are pointing out are things that would cause a lack of efficency and people to see less than the true doubling effect from 14.7psi. having the right sized turbo and good gas and most of your timing are all things that would help you get closer to a true doubleing.
i am still missing something here, from what i have read going with 14.7psi theoreticaly the best you can do is double but since you can't be 100% efficient that actualy doubeing is not posiable. that is unless there is something else thrown in to the equasion like an ice filled intercooler.
Originally Posted by eviltwins
In the grand scheme of things, boost means almost nothing. Can you compare the power produced by a 60-1 HiFi and T76 Q-trim at the same boost levels? Running both at 10 PSI, they're both making the same amount of boost, but the T76 is going to be making a lot more power because its moving a lot more air.
Similar effect as an Ice water intercooler, denser intake charge.
a real general SWAG on a stock cammed, stock headed LS1 is about 30 RWHP per psi on a reasonibly efficient turbo setup. Seen it time and again on TTi kits, and incon kits, and QMP kits.
Trending Topics
also, if i am correct, as you raise boost, you increase the volumetric efficiency of the motor, therefore allowing more power to be made, than the stock *(1 +
(14.7/boost)
Ryan
(14.7/boost)
Ryan
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo I have a 348ci going thru a T400 u/locked and I probably make 360rwhp n/a. On blower I've made a high of 746rwhp with a lean A/F, so ~750rwhp thru a T400 would be over 800rwhp with an M6. How does that help your calculations? 400rwhp say for 17 lbs of boost equals what, 23.5 rwhp per every lb of boost so almost 30fwhp per lb of boost for me. My setup uses more power to turn the blower so it's not as effecient but we'll be able to see what all the big number setups do at the track this year. And I am probably going to step it up a bit and be a firm #2 behind Harlan on numbers. I'm sure he can go 850rwhp for sure with enuff fuel.
FormerVendor
Joined: Dec 2001
Posts: 2,444
Likes: 2
From: WWW.SPEEDINC.COM
Originally Posted by Pro Stock John
And I am probably going to step it up a bit and be a firm #2 behind Harlan on numbers. I'm sure he can go 850rwhp for sure with enuff fuel.
I think if he turned up the wick it would do 1000+rw easy.
FormerVendor
Joined: Dec 2001
Posts: 2,444
Likes: 2
From: WWW.SPEEDINC.COM
Originally Posted by Pro Stock John
That would be a pretty high bar Jim. 
So, you think a solid roller, dry sump 348 with dual T-66's, air/water coolers, and open downpipes is good for only 850rwhp?
Hitting 1000rwhp IMO would be interesting and he will find all the weak links of his current setup, I'm sure he would end up needing a fancier clutch and maybe to upgrade some of his fuel components.
TECH Resident
Joined: Aug 2003
Posts: 948
Likes: 0
From: orlando, florida
a real general SWAG on a stock cammed, stock headed LS1 is about 30 RWHP per psi on a reasonibly efficient turbo setup. Seen it time and again on TTi kits, and incon kits, and QMP kits.[/QUOTE]
Damn i wish i made 30hp per psi of boost i only see about 12hp per psi.
I can`t understand what is so magical about his kit that it makes twice the power of a TTI kit at the same psi when there almost identical in design. Does rob know a magic switch in edit that when you flip gives you 200 extra HP because he`s the only one that can get these single turbo cars to perform with these amazing dyno numbers. He needs to start teaching other tuners his secrets so some of us can get the power numbers he`s getting.
Not bashing QMP in any way Just wondering why rob is the only tuner that can get big power out of these kits?
Damn i wish i made 30hp per psi of boost i only see about 12hp per psi.
I can`t understand what is so magical about his kit that it makes twice the power of a TTI kit at the same psi when there almost identical in design. Does rob know a magic switch in edit that when you flip gives you 200 extra HP because he`s the only one that can get these single turbo cars to perform with these amazing dyno numbers. He needs to start teaching other tuners his secrets so some of us can get the power numbers he`s getting.
Not bashing QMP in any way Just wondering why rob is the only tuner that can get big power out of these kits? 
Originally Posted by INTMD8
It is alot of power.
So, you think a solid roller, dry sump 348 with dual T-66's, air/water coolers, and open downpipes is good for only 850rwhp?
So, you think a solid roller, dry sump 348 with dual T-66's, air/water coolers, and open downpipes is good for only 850rwhp?
From what I have seen the gen3 will start to have head gasket problems around 1200 at the flywheel.
I think Harlan may be using a stock crank also, not sure of its limits but I would stand back if he winds her up that high.
Should be a very exciting year coming up.... can't wait for summer!
Kurt
FormerVendor
Joined: Dec 2001
Posts: 2,444
Likes: 2
From: WWW.SPEEDINC.COM
Originally Posted by 427
Generally a TT with good cylinder heads is good for 4.5-5 hp for every CI at the flywheel.
From what I have seen the gen3 will start to have head gasket problems around 1200 at the flywheel.
I think Harlan may be using a stock crank also, not sure of its limits but I would stand back if he winds her up that high.
Should be a very exciting year coming up.... can't wait for summer!
Kurt
From what I have seen the gen3 will start to have head gasket problems around 1200 at the flywheel.
I think Harlan may be using a stock crank also, not sure of its limits but I would stand back if he winds her up that high.
Should be a very exciting year coming up.... can't wait for summer!
Kurt
In regards to the head gasket problems around the 1200 flywheel horsepower level, was that a nitrous, supercharged, or turbo car? (or all of the above)
If the LS1 is horsepower limited due to head gasket sealing, I think a turbo car will be able to go the farthest before reaching that limit. (by far)
We should have an awesome year ahead of us.
Originally Posted by INTMD8
In regards to the head gasket problems around the 1200 flywheel horsepower level, was that a nitrous, supercharged, or turbo car? (or all of the above)
If the LS1 is horsepower limited due to head gasket sealing, I think a turbo car will be able to go the farthest before reaching that limit. (by far)
We should have an awesome year ahead of us.
If the LS1 is horsepower limited due to head gasket sealing, I think a turbo car will be able to go the farthest before reaching that limit. (by far)
We should have an awesome year ahead of us.
No question the turbo engine will reach the highest numbers before pushing gaskets.
Just praying for a early summer......
Kurt
Originally Posted by INTMD8
It is alot of power.
So, you think a solid roller, dry sump 348 with dual T-66's, air/water coolers, and open downpipes is good for only 850rwhp?
So, you think a solid roller, dry sump 348 with dual T-66's, air/water coolers, and open downpipes is good for only 850rwhp?
LOL
And yes Kurt, I'm still on a stock crank. I'm actually curious to see what it takes to break it
And now that i know why i was running out of fuel, we can spin her up and twist the **** a little more.better order some more pulleys John
