Is there a way to change rev limiter?

[PorterzSupra]

Is there anyway to bump the rev limiter up or even disable it on a stock ECU w/maft? Maybe I can get a different ignition system to do this? I wanna be able to rev to 8 or at least higher 7 to spool the T66 harder because I noticed if I shift early into third from second I get slight lag but if I bring the revs up to redline I dont get any lag at all so I wanna bring the revs up a few hundread rpms higher without cut. There has to be a tac sensor wire u can dissconnect or fool in order to take off the cut because its gettin the info from somewhere....

 

[gixxer750]

Stock valvetrain? I wouldn't rev anywhere near 8 grand... Maybe 7000...

I think you have to have a standalone to do this.

 

[bigboost7m]

Or you can get an aftermarket ecu, like the Mines ECU, which is programmed with a higher rev limit, different fuel trims etc, great for an upgrade. Contact spoolinT78 i believe he has one if your interested.

 

[PorterzSupra]

There MUST be a way to trick the RPM sensor, like you can do to the fule cut sensor. When reving to near rev cut my T66 has 0 lag going into 3rd but sometimes I hit limiter. When I shift early like 6 my T66 laggs going into 3rd I only need a couple hundread RPM difference

 

[Supracentral]

There MUST be a way to trick the RPM sensor, like you can do to the fule cut sensor. When reving to near rev cut my T66 has 0 lag going into 3rd but sometimes I hit limiter. When I shift early like 6 my T66 laggs going into 3rd I only need a couple hundread RPM difference

Yes, you could with a signal clamp, but that's dangerous and not a very good idea. What would happen is even though you are turning the motor 7,000 rpm the ECU would be convinced it was running at a lower RPM.

 

[againstdawall06]

try getting a bov that holds boost better, or shift faster maybe. i dont think reving a 7m higher is gunna solve any problems just create them....unless you upgrade your valve train.

 

[PorterzSupra]

I just need to raise it a few hundread RPM im not talkin about running it all crazy lol you try to keep a T66 with a .84 exhaust side from loosing its spool between shifts, u need to keep the rpms up high were not talkin about a CT 26 that maxs out at 3,800 - 4 grand. its not bad at all but now and then I go slighty over and get the cut, BTW what is a "SIGNAL CLAMP" Supracentral is talkin about? Its a risk im willing to take, I have another low miles motor here anyway.

 

[tubbie]

You need a standalone or rebic LC or the crystal mod (never seen it done to anyones though).

Also, why the need for an upgraded valve train if your only going to 7500 rpm? Anyone have facts that says you can't, other than the "I heard this from him who heard it from that guy, who... etc etc..."

 

[againstdawall06]

only the "rev to 8" stuck in my mind when i read it. and that seems high on the 7m which is not good at reving high. or so iv read.

 

[GrimJack]

Modified ECU (Mines, TechTom), full standalone, or if you have the earlier ECUs, a lot of luck, and don't mind risking trashing your ECU you might be able to put a difference frequency crystal on the board and increase it that way. From what I understand 2 or 3 people have tried the crystal method, and only one has worked properly. There are no documented methods for doing this, so you'll have to be DAMN good with a soldering iron and know your way around the inside of the stock ECU. If you take this route and it works, please take some photos so we can see how to do it.

At some point beyond the stock redline you are going to run into valve float. Where exactly that will happen is anyone's guess. It might happen at 6300rpm, and it might not happen until 14000rpm. If it does happen, it won't be good for your engine.

 

[Nick M]

Anyone have facts that says you can't, other than the "I heard this from him who heard it from that guy, who... etc etc..."

You mean besides the redline the engineers built into the car that spent thousands of man hours devoloping the car?

 

[GrimJack]

You mean besides the redline the engineers built into the car that spent thousands of man hours devoloping the car?

Ok, I'm NOT saying that anyone should push their redline... however, this logic is flawed.

The same engineers put fuel injectors capable of double the stock horsepower in the same car. They also built a bottom end capable of holding well over double the stock power. Furthermore, they built a chassis capable of holding 3-4 times the stock power levels.

 

[jetjock]

An ecu based rev limiter? In the 7MGTE? Hmmm....

 

[IJ.]

JJ: They tell me there is a hardcut limiter built in but I can't ever remember hitting it when I had a stock ECU.

 

[GrimJack]

I bounce off the damn thing all the time in first gear.

I'm pretty sure this is the procedure for checking that it works properly... http://www.cygnusx1.net/supra/library/TSRM/fi/FI_125.html

 

[Dirgle]

The same engineers put fuel injectors capable of double the stock horsepower in the same car. They also built a bottom end capable of holding well over double the stock power. Furthermore, they built a chassis capable of holding 3-4 times the stock power levels.

This sort of thing along with a low redline is the way engineers design a motor and chassis capable of a few hundred thousand miles, as well as enable them to offer a longer warranty. Mitsubishi admits doing this on their newer cars. Over engineer it and then turn down the power to provide a long lasting platform.

 

[shaeff]

anyone remember racerjake? pre '89 ECU's FTW.

-shaeff

 

[jetjock]

Grim, at what rpm does this happen? If rev limited it has to be above redline. Are you saying you're exceeding redline in first gear? I was always under the impression the 7MGTE (at least in my 87) did not have a rev limiter. Nor is it mentioned in any of the factory TCCS documentaion I have so I'd like to have this confirmed. I'm aware of the fuel cut rpm function but I'm of the opinion it serves another purpose.

 

[PorterzSupra]

my 88 has it, I dont hit it in first ever, only in second sometimes in the gear change when the readend dances back and fourth for 5 or 6 seconds and at the end of 2nd when im trying to keep the turbo spooling hard for 3rd

 

[IHI-RHC7]

JJ, Fuel cut is a function of airflow vs RPM to determine an ovreboost condition. Spark cut kicks in at any load at around 6750 in pre 89 cars. In post 89 it is at 6250 or so and an 89 could go either way depending on the motor mounts, crank, etc. (not that they have anything to do with rev limit, but they indicate which era the vehicle is)

FYI My dad and I have rev'd to 8400 on stock valvetrain with no float, no spit shims, etc. Why? well, the tach didn't work with AEM yet and we figured we'd shift when the power let out. Oddly enough, with a T-78 the power didn't let out for quite some time. Our valve springs are quite beefy and it's big cams that spit shims, not revs.