What kind of engine RPM's can i pull

[KevinHoward8509]

Below is a list of the engine mod's i have on my car. i bought it used and am curious what everyone feels is a comfortable engine RPM for me to pull when at the strip. i am not sure what the rev limiter is set to as i did not have all the parts installed so not sure what the tuner set them at.

Engine
- Procharger P-1 Stage 2 Kit Intercooled
- HP Tuner
- ATI Super Damper 2% Underdrive Balancer
- AEM Wideband with Gauge
- TSP Supercharger Camshaft 224/240 .615/.615 112 +3
- Brian Tooley Dual Valve Springs
- Brian Tooley Chromoly Pushrods
- Brian Tooley Titanium Retainers
- GM 3 Bolt Conversion
- New GM Oil Pump
- Injector Dynamics ID 1050x Injectors
- Kooks 1 7/8" Long Tube Headers #6511
- Kooks 3" Catted (Hollowed Out) Exhaust 22505200
- JBA Power Cable Ignition Wires
- Mishimoto Aluminum Radiator
- Mighty Mouse Oil Catch Can
- Edelbrock (Red) Valve Covers

[Tarendor]

Its not a matter of what you "can" pull its a matter of what RPMs are you making peak power at and should shift at to maintain the proportional gain at.

[KevinHoward8509]

Originally Posted by Tarendor

Its not a matter of what you "can" pull its a matter of what RPMs are you making peak power at and should shift at to maintain the proportional gain at.

I agree 100%

I have the dyno chart but it was on a DYNOJET so i see wheel speed instead of engine RPM's.

Just trying to see what others are pulling the RPM's to on their cars i am going smaller pulley on my procharger and tuning it to E85 but i dont want to over spin the procharger. ive been shifting it around 6500k currently.

[NEstyle]

It also depends heavily on valvetrain stability.


All cars like different shift points. You will just have to experiment to see what it likes.

[Vegas Bound]

Peak HP is at 6600, peak torque at 5400. Everything after that is diminishing returns.

[acammer]

Originally Posted by Vegas Bound

Peak HP is at 6600, peak torque at 5400. Everything after that is diminishing returns.

But, shifting right at peak power is not a strategy to maximize power. Rather, you need to look at the power curve before and after the peak HP in conjunction with shift recovery rpm drop to determine shift points. A car with a big converter may only need to go a couple hundred RPM beyond peak as it may only have 1000rpm of shift drop. A stick car can have more than double that, my 1-2 and 2-3 shifts have over 2200rpm of shift recovery rpm drop. In either case, you want to have the highest average hp throughout the duration of the gear.

In my stick car, I make peak power at 6500rpm, but I target a 7200rpm shift point. That puts my shift recovery rpm drop at right about 5000rpm. This gives me the best average HP with my combination. If I was to shift at 6500 (peak hp) then my shift recovery rpm drop would be at 4500rpm - and that range would yield less power, and less acceleration.

So, back to the original posters question - with a centrifugal peak power usually just keeps climbing as you increase the rpm (and therefore the boost), and they typically will like a nice high shift point. That said, you don't have a particularly aggressive camshaft or pulley combination, and there will probably be a point where it starts to roll over. It's a guess, but I would think that will like a shift point somewhere in the 6700-7000rpm range, depending on where shift recovery lands.

Is it stick or auto? What converter, what gears? Lets see the dyno graph, we can probably infer a few things from what we see there.

[KevinHoward8509]

Originally Posted by acammer

But, shifting right at peak power is not a strategy to maximize power. Rather, you need to look at the power curve before and after the peak HP in conjunction with shift recovery rpm drop to determine shift points. A car with a big converter may only need to go a couple hundred RPM beyond peak as it may only have 1000rpm of shift drop. A stick car can have more than double that, my 1-2 and 2-3 shifts have over 2200rpm of shift recovery rpm drop. In either case, you want to have the highest average hp throughout the duration of the gear.

In my stick car, I make peak power at 6500rpm, but I target a 7200rpm shift point. That puts my shift recovery rpm drop at right about 5000rpm. This gives me the best average HP with my combination. If I was to shift at 6500 (peak hp) then my shift recovery rpm drop would be at 4500rpm - and that range would yield less power, and less acceleration.

So, back to the original posters question - with a centrifugal peak power usually just keeps climbing as you increase the rpm (and therefore the boost), and they typically will like a nice high shift point. That said, you don't have a particularly aggressive camshaft or pulley combination, and there will probably be a point where it starts to roll over. It's a guess, but I would think that will like a shift point somewhere in the 6700-7000rpm range, depending on where shift recovery lands.

Is it stick or auto? What converter, what gears? Lets see the dyno graph, we can probably infer a few things from what we see there.

attached is a copy of the dyno sheet.

The more comfortable i get with the car the more im willing to push it. i was shifting around 6700 rpm the last couple days and am noticing how much nastier it is up there which understandably so being the way its setup.

The car is a M6 with a 3.91 rear end. the current pulley setup is a 3.90 on the top and a 7.625 on the bottom and i want to go with a 3.40 on the top but if i pull 7000 RPM's that will put me at 64,500 impeller rpm's and max on the p1sc is 65k so i dont want to pull that many rpm's.

i mostly street race and just get on it from time to time i dont go to the track and just run the shit out of it for a half a dozen pulls but i do run my car harder than i would say most do while daily driving.

[Vegas Bound]

I spin my LSA to 27000 rpms on a max of 24000. Send it.

[KevinHoward8509]

Originally Posted by Vegas Bound

I spin my LSA to 27000 rpms on a max of 24000. Send it.

haha!!! my buddy keeps telling me the same thing.

Between that and the 12-13lbs of boost ill be running on E85 i feel like im pushing everything to the max haha.

[acammer]

Looks like it peaked at 138mph, which is ~6500rpm on a 28" tire. With a stick I'd definitely target a 7000+rpm shift. I'm sure it would carry out pretty good as far as you're willing to spin it with a centri - it really becomes a question for the valvetrain.

The 660 platinum should be ok out to that 7500 range, Ti retainer is helping keep it light. Stock LS3/7 lifter I start to question out past 7000 and start to recommend GMPP's or 2110's when we put together cam packages. That said, my stock 42k mile LS3/7 lifters and 660's with tool-steel retainers see 7200 regularly, and have been out to 7600+ on a few occasions without issue.

I would maybe start by targeting a 7000rpm shift. If you're at the track and pretty consistent in your trap speed you can try a pass shifting at 6700, and another at 7300 to see if you make any noticeable gains/losses.

[Greenhornet2]

I'd also say set your limiter to 7k-7200 and see how it feels. you need a little rpm buffer in the lower gears as the rpms climb quick. I need to bump mine a couple hundred rpm I think its at 6800 I peak at 6700 I don't have enough time to shift in the lower gears before I hit the limiter as the car still feels like it's pulling.

[Vegas Bound]

Originally Posted by KevinHoward8509

haha!!! my buddy keeps telling me the same thing.

Between that and the 12-13lbs of boost ill be running on E85 i feel like im pushing everything to the max haha.

Try 17.5 lbs on e85.

[KevinHoward8509]

Originally Posted by Vegas Bound

Try 17.5 lbs on e85.

is that a joke haha.

The pulley i ordered should get me abour 12-13 and thats all the p1sc can put out for me. Ill be spinning close to max RPM's for that blower.

[Vegas Bound]

Originally Posted by KevinHoward8509

is that a joke haha.

The pulley i ordered should get me abour 12-13 and thats all the p1sc can put out for me. Ill be spinning close to max RPM's for that blower.

No joke. At sea level, I make 17.5 lbs and use e85. At altitude, I'm down to 14.