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Max safe RPM for shifting

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twich12

New member
so trying to tune the transmission on my 02 GP SE (3100) and was wondering what the safe rpm limits are on the engine? nothing has been done to the engine other than the LIM replacement (newer rev) and by this weekend i will install zzp's "performance shift kit" to eliminate some lull... other than that it is all exhaust and intake mods- CAI, 56mm TB, u bend, "performance" muffler, dog bone flip/bushings, t-stat

i would appreciate if the response was kind of like
xx00- max safe
xx00- try not to go over this too often
xx00- dont go over this but its not insta-death
xx00- engine is garunteed to die if not the first not then the next few times
xx00- OMFGWFTDIDYOUDO?!?!?!? *cylinder shoots through hood*
 


You are not going to find magical horsepower in shifting late. Your intake/valvesprings are going to give up before stock rev limit....

Bump it 200rpms, and call it a day.
 
darkhorizon said:
You are not going to find magical horsepower in shifting late. Your intake/valvesprings are going to give up before stock rev limit....

Bump it 200rpms, and call it a day.
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im not looking for magical horsepower, but my butt dyno tells me that the stock shift points are not taking full advantage of the power band

and good, thats what i have been driving around with and it has improved my 3rd gear noticeably (bumping my 2nd gear made my 3rd start a bit higher which minimized a large drop in acceleration)
 
but my butt dyno tells me that the stock shift points are not taking full advantage of the power band
Click to expand...

If for some reason this is true... 200rpms should give you enough.

At the end of the day, its slow as dirt no matter what you shift at.
 
Trying to push your shifts to 5500 or 6000 isn't going to gain you any more hp. You are better off shifting at 4800 to 5000 and not worry about valve float on stock springs. Not to mention your tranny will thank you.
 
The problem here still is the 3100. No matter what your doing, if you keep it naturally aspirated...it isn't going to be fast. Or faster.

I'm sure it runs better than a stock 3100, but you might as well boost it with all the trouble your going through trying to make it go fast N/A.
 


thanks darkhorizon and zef_66! so instead of bashing my 3100 why cant i just get an answer? ya know what, anyone on this forum that does not have a turboed ls9- your cars suck and your better off just getting a turboed/boosted ls9.... and im not going through any trouble, if you havent noticed i have yet to do any expensive modding.... custom CAI, 56mm TB off of milzy's for 20 bucks, u bend delete, flowmaster super 44 (it was cheaper than getting the OE muffler), 180* tstat, zzp performance shift kit, tuning is the most expensive thing i am doing and im using a friends tuner. everything i am doing is very inexpensive and is helping me learn more about my car, i am not a seasoned mechanic and am using this car as a learning project. perhaps later down the road i will be able to be in the super cool twin turboed ls9 club but for now im just modding on a budget and learning my way around an engine compartment
 
they may be hard on you...but they're right in this case.

if you have no serious mods you should not be changing shift points. If you change the powerband by an appreciable margin by ways of ported heads/camshaft/balanced rotating assembly/lightweight valvetrain/etc then increasing or modifying shift points can have a profound impact on performance. otherwise...leave it alone.
 
twich12 said:
thanks darkhorizon and zef_66! so instead of bashing my 3100 why cant i just get an answer? ya know what, anyone on this forum that does not have a turboed ls9- your cars suck and your better off just getting a turboed/boosted ls9.... and im not going through any trouble, if you havent noticed i have yet to do any expensive modding.... custom CAI, 56mm TB off of milzy's for 20 bucks, u bend delete, flowmaster super 44 (it was cheaper than getting the OE muffler), 180* tstat, zzp performance shift kit, tuning is the most expensive thing i am doing and im using a friends tuner. everything i am doing is very inexpensive and is helping me learn more about my car, i am not a seasoned mechanic and am using this car as a learning project. perhaps later down the road i will be able to be in the super cool twin turboed ls9 club but for now im just modding on a budget and learning my way around an engine compartment
Click to expand...

No one is really bashing you. There are quite a few members here that have started out in your position and over time they learned things by trial and error. Another thing you've got to understand is that we get a ton of people that ask the same stuff over and over so the seasoned guys here may come off as a little harsh but they are only trying to help you from spending $$$ on mistakes that could have easily been avoided.
 
twich12 said:
thanks darkhorizon and zef_66! so instead of bashing my 3100 why cant i just get an answer? ya know what, anyone on this forum that does not have a turboed ls9- your cars suck and your better off just getting a turboed/boosted ls9.... and im not going through any trouble, if you havent noticed i have yet to do any expensive modding.... custom CAI, 56mm TB off of milzy's for 20 bucks, u bend delete, flowmaster super 44 (it was cheaper than getting the OE muffler), 180* tstat, zzp performance shift kit, tuning is the most expensive thing i am doing and im using a friends tuner. everything i am doing is very inexpensive and is helping me learn more about my car, i am not a seasoned mechanic and am using this car as a learning project. perhaps later down the road i will be able to be in the super cool twin turboed ls9 club but for now im just modding on a budget and learning my way around an engine compartment
Click to expand...

And if you go back and read, we did answer your question. Basically, stay at stock, or not much more than that. The reason being is you will start to get valve float and loose HP. I just don't think you want to accept that answer.
 
Point in case...you can't just keep revving the motor higher and higher...at some point...your going to put a strain on something that isn't meant to be ran that high in the RPM range...and it's gonna break. Then your gonna be wondering, huh...those guys were right.
 


bluegtp91 said:
The problem here still is the 3100. No matter what your doing, if you keep it naturally aspirated...it isn't going to be fast. Or faster.

I'm sure it runs better than a stock 3100, but you might as well boost it with all the trouble your going through trying to make it go fast N/A.
Click to expand...



+1


Good reliable DD motor but you're not going to wring much more out of those 3.1 litres without really getting inside the engine.
 
twich12 said:
im not looking for magical horsepower, but my butt dyno tells me that the stock shift points are not taking full advantage of the power band

and good, thats what i have been driving around with and it has improved my 3rd gear noticeably (bumping my 2nd gear made my 3rd start a bit higher which minimized a large drop in acceleration)
Click to expand...

yes im quoting myself because apparently my response to what DH said went unnoticed.... and thank you zef, i was mostly talking to blue because he seems to thread crap every 3100 thread

edit: blue does give out useful information, but its usually after he makes his crappy entrance
 
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I would keep the stock shift points. Keep tinkering and learning while trying to to spend much cash, then move to a better platform. Like most on here do.
 


or if you really want turbo the damn thing lol, they made a stock turbo car in 89-91 i believe...its pretty easy to just swap most of the parts over, boom 215 horse right there, add a bigger turbo, intercool it....annd that should put ya at around 300 to the crank on full boost. well thats what ive read anyways lol, i would look up some more information on this topic
 
twich12 said:
yes im quoting myself because apparently my response to what DH said went unnoticed.... and thank you zef, i was mostly talking to blue because he seems to thread crap every 3100 thread

edit: blue does give out useful information, but its usually after he makes his crappy entrance
Click to expand...

Sorry that I'm just trying to save you the trouble before you waste your time with it...but go ahead.

Next time, I won't give any advice...I'll just sit back and watch. I'm just trying to tell you since I've been there...done that...save your money...and put it into something that actually makes power...that's it.
 
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