One more quick Question ~ This time ECU rev limit.

[mushroom_toy]

So yeah I searched and didnt find much. As most of you know my car used to be auto, then I swapped to five speed, but retained the auto ecu. Anyway I have a rev limit, or fuel cutoff or something at around 6500, is there anyway around this? On the new engine Im looking for a limit of around 7200. I was gonna grab a 5 speed ecu tomorrow and see if that helps, but if not theres not need.

I know Im posting a lot of crappy threads, but just trying to tie up all my loose ends.

[Civic Accord Honda]

my 88lxi 5speed reved to 7200 rpm.. made power up to there too :D

[guaynabo89]

in my 87 oem Accord service manual it says fuel cut kicks in at 6350. Could be differen t in the 88-89 since they changed springs for that head.


I don't know how to get past the fuel cut with an oem ecu. Apexi makes a rev/fuel limiter, but that's a little pricy unless you get it used.

[2oodoor]

gotta be a hack there, doesnt it go thru relay? pull up the wiring schematic and see if bypassing the signal around ecm is feesable at the relay.
Using an aftermarket FPR, and using a signal just from ignition for relay seems feesable. I think it knows the rpm by the wire on the neg side of coil same as carbed cars.

[carotman]

The rev limiter is inside the ECU. It cuts fuel to the injectors when it reaches this limit.

There is a way to modify the limit. I posted the BIN file from an OKI 88-89 ECU a while ago here. I haven't found where is the rev limiter in it yet.

[mushroom_toy]

^So technically getting an 86-87 manual ecu probably wont change things?

[guaynabo89]

no.

[mushroom_toy]

Damn. Oh well at least thatll save me some cash. :)