I'm not looking for the instructions on how to remove the speed govenor, I have no need for that. What I am looking for is to bump up or completely remove the rev limiter. On the ecotec it stops at 6400rpms.
Is there a shop other than JBodyPerformance.com that can change the rev limiter?
How high can I safely go with this engine? 7000? 7500?
How high can the transmission safely go?
i am thinking your gonna get flammed
Why? This is a legitimate question. My car with the current cams is not hitting the peak hp until the rev limiter or right after.
If I get flamed, it's by someone who is going to tell me to search, or because they don't know what they're talking about
Eh, the problem just isn't the cams man, its the whole engine. I would get it blueprinted and balanced before going over the rev limiter. Just because you are still making power there doesn't mean the engine can handle higher revs.
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I would say 7000 is DEF. still within safe ranges but would NOT go any higher
LE61T PTE6262 Powered 
arnjolt look at ur current hp curve and look at the pervious hp curve...u would gain an insane amount of hp if the limiter was stretched to 7000 b/c before the limiter before the pervious dyno the hp was already dropping off. would be sweet as @!#$. (but i wouldnt wanan see how much torque u would have...looks like u had like 80-90 at the normal rev limiter)
MY 2003 SUNFIRE
i'm sorry, i was looking at the wrong side of the graph. looks like u were at 120 something and it dropped off considerably!
MY 2003 SUNFIRE
I got this from GM the 4t40e with mn4 transaxel max eng.torque 190 lb.ft max gear box torque 325 lb.ft max shift speed 6500rpm. hope this helps you.
Thats Him Officer The WICKED One.
at that high of r.p.m you wont get as much power, and the damn govenor is another story, i have to drive down to my uncles in kansas city to get that takin out. but it will be worth becuz when i boost in summer i will most definetly hit that in the quarter.
the rsm race car dont even have a rev limiter and goes beyond 8 i dont think you will have any problem up to 7500, also what the 4t40 can handle really doesnt matter seeing as how this guy has a manual
1989 Turbo Trans Am #82, 2007 Cobalt SS G85
Quote:
at that high of r.p.m you wont get as much power
have you seen his dyno? his before hp begins to drop off as its coming to the rev limiter. although with the cams his car is still creating more power the higher its going. my guess is if he extends his rev limiter he will be creating 15-20 more whp then when he didnt have the cams. b/c as the power starts dropping without the cams and thats when the power kicks in with the cams. if the graph was extended to show more rpms if you first looked at the lowest point of power (without the cams in) and look for the the same point (with the cams in) i bet you would see a good 15-20 whp difference. well there would only be one way to find out.
MY 2003 SUNFIRE
I was thinking the reason GM limits the rpm is for the sake of the automatic.And it is easier for them to mass produce all the PCM,s with the same rev. limit . I am sure the engine can wind up another 1000 rpm above the stock setting no problem. I think you would have to reflash the PCM to raise the upper limit.
Thats Him Officer The WICKED One.
The rev limiter is put in place because our engines aren't built to be high rev engines - they're low torque low rev engines from factory.
One of the main problem with trying to get up to 7000 rpm is floating your valves - a huge possibility with GM engines, unlike Honda's.
As for removing it - I don't know any street driven eco that has had it done... but I'd be pretty afraid if I were you to go that high....
Looking at your HP curve you are definitely making power to redline, but I don't think finding a way to bump the redline (expensive) is the way to go....
Those cams are simply too agressive for the car with stock timing. You're 100% better off getting adjustable timing gears and finding out what it takes to get those cams to run the way they should. My guess is that the car is letting out more exhuast than its taking air in, which is why the low end on your car went to all hell. Remember, flow = hp and moving the curve up... and it seems you're overflowing what the engine wants to do.
That is my opinion - I posted in your other post but it seems nobody wants to learn from my experience. That is fine, it's not my money - but I'm just trying to help.
Good luck.
-Chris-
-Sweetness-
-Turbocharged-
Slowly but surely may some day win this race...
ive accidently put her over 7k once
downshifted into the wrong gear wasnt going to fast luckly
ouch
1989 Turbo Trans Am #82, 2007 Cobalt SS G85
I agree that adjustable cam gears would be the safest and best solution, since you could tune your power band and who wouldn't like higher torque at lower RPMs.
well logic states advancing the cam timing would increase lower rpm power at the expense of revs, but there's no guarantee that that cam setting would be best with those cams. 7000 rpm doesn't sound to unrealistic with an eco, but as mentioned i would consider stronger valve springs to prevent valve float, and maybe upgraded rod bearings as well. What some of you i think are forgetting is that the eco was over-engineered, much like most toyota engines. If the stock rods (the weakest link in the stock shortblock) can still handle almost 300 hp, i think its safe to say an extra 600-700 rpm is going to be too terribly hard on them. Would i spend all of my time at 7000 rpm? No, but if you're only seeing that rpm while racing which is probably less than 10% of the time a street driven car is running, it most likely won't be an issue. The only problem is its kind of uncharted territory, so everyone is just guesstimating this until someone wants to chance it on their motor to prove the theories right or wrong.
Arrival Blue 04 LS Sport
Eco
Turbo
Megasquirt
'Nuff said
