Rev Limit

[IJ.]

My 92 with the stock ECU would hit the rev limiter right around 6200-6300 rpm's. I have hit 6600 rpms peak (shown on my AVCR), but I think the ECU just didn't catch it in time.

With the AEM, I'm now reving to 7300, which is a night and day difference. I can now use the 62mm turbo much better without bumping into the revlimiter constanty.

That's interesting MrSupra thanks for the input!
(so a pre 89 ECU has an actual higher limiter setting, good to have confirmation)

 

[Figit090]

Horsepower = Work X Time / 5252. Work = torque and Time = RPM

If you make the same torque at a higher RPM you Yield More horsepower.

For example [words]
The trick is knowing when enough RPM is enough. You want to shift when the engine will return to the beginning of the meaty part of the torque curve. Any more then that and your wasting time.

Cool thanks for the explanation.

 

[MRSUPRA]

/\ Yes, the 6200 rpm cut was pretty lame when using a "real" turbo. Not sure if my tach was 100% accurate, but it was probably pretty close.

 

[supradjza80]

/\ Yes, the 6200 rpm cut was pretty lame when using a "real" turbo. Not sure if my tach was 100% accurate, but it was probably pretty close.

My tach will sometimes bounce around 6250/6300 but my AVCR is showing 6500-6700 max speeds when I hit the limiter. Sometimes the tach will bounce a little higher up to 6500, but that is well with in the range of accuracy for a factory tach.

 

[IJ.]

Yep my factory tach was never what you'd call accurate, I had it tweaked to work with the standalone so they got it +- 50 rpm but compared to the ECU tach it was slow to respond.

 

[MRSUPRA]

Interesting. I noticed my AVCR and factory tach was always pretty close at low engine speeds, but I could never compare at full throttle. My peak hold RPM did hit 6600 rpm's one time, but I also remember it hitting much lower than that several other times when I bounced it off the limiter.. Wish I could go out and compare right now. Too bad my tach is not hooked up any more.

 

[supradjza80]

My avcR has read 6600 + many times with a stock ECU. at low RPM it just appears dead accurate due to the fact that the amount it is off is smaller. Mine correlate almost perfect at low rpm. Plus with it idling at 650 its hard to know if the tach is at 650/660/680 etc. and its a pretty vague measurement.

 

[Heavy D]

they lowered the rev cause of cylinder 2 and 5 counterbalance and heavier crank

 

[VanSupra]

Stock gte turbo cams are pretty well pooched torque wise by 6400ish rpm. You can continue to gain hp by reving higher, but at the cost of your wheel torque values declining. Not good if you're racing the straight track..I shift my car at 6500rpm.

 

[prsrcokr]

Any techtom dealers still out there, a new map is one method. When I got mine I asked for stock rev limit since it's been the original bottom engine. Not sure what I'll do with the new engine but I don't plan to use that rev range often.

 

[figgie]

reg reimer over at RCTS still does. Give them a call though.

http://www.monsterhorsepower.com/
http://www.monsterhorsepower.com/techtom/tindex.html