Stock rev limiter raise/disable

[PorterzSupra]

I know there have been a couple posts about this but no one ever got to the bottom of it. The ECU will cut power to a random set of injectors at or above redline. While still running a piggybacked ECU there has to be a way to cap the RPM signal much like the MAFT does with airflow signals. If I had some idea of the voltage range the injectors run off of maybe it could be restricted 5% for example raising the limit a few hundread rpm. The car might also run 5% leaner just like how the MAFT works but it could be adjusted.

The second idea would be to tap into the harness and splice the injector sets into one another so when for example power is cut to a set it will still get the signal from the set that is still being fed because the rev limiter does not cut fule completely just to a "random" set. You would have to make sure your splicing into the same set of pistons on the crank but it seems like it could be done.

I have even heard of there possibly being a wire that you can remove to disable rev limit FC but it has not been confirmed yet.

When you start running bigger turbos and higher duration cams your moving your powerband up and the rev limiter will get in your way a few hundread RPM too soon. A stock engine would not benifit from it but us higher modded guys would esp with aftermarket cranks, rods exc.

There are some ppl that will say its not a good idea blah blah blah but I dont care, I am willing to take the chance and reap the benifits if I find a way to do it.

 

[MKIIINA]

i think your thinking is slightly flawed there. you are looking at it that the ecu only reads rpm and determined what the injectors should do. you need to remember there is an 02 sensor, temp sensors, cps, knock, and a few other sensors that are feeding information to the ecu. either on of these would be trying to trick the ecu. granted im not saying that your idea would not work but i think you need to consider it some more. if you just want a few hundred more rpms and have a 90+ 7m cranked car then you can try and find a 6m'd ecu that will let you rev 250-350 higher. i am running this setup currently and it works seemlessly as it is a toyota engineered peice.

another idea is to just find a mines, blitz, or a reg r. modified ecu that lets you rev alot higher. remember also that as nice as it would be to rev that high if you have the crank, pistons and rods the bigger gains will come from head work. porting and even better using larger valves are what are going to bring bigger gains than just revving higher.

 

[PorterzSupra]

According to the manual it looks like # 1&6, 4&5 and 2&3 are on the same injector signal. So when the computer knocks out a set I guess it randomly picks on one of thoes sets?

 

[PorterzSupra]

If I take a tac reading on the signal wire goin to the ECU and then put a cap after it but before the ECU then have another tac reading the caped signal I could get the real RPM and then the RPM that the computer is reading. So as long as I keep the cap reading just below the redline I could raise the limiter and monitor the real RPM then find the correct cap setting based on the % of restriction from the original signal.