rb20 ecu with rb25det

[armygsrcivic]

ok here we go guys. i just finished installing a t3t4 turbo setup on my rb25det s13. the problem is when im driving the turbo takes forever to spool up and there isnt much power being produced and it wont boost past 7psi even tho i have a manual boost controller that is all the way backed off. i made sure all the couplings are tight and made sure there were no vacum leaks. i have no idea on whats going on. so far the mods that i have are... t3t4 turbo with top mount manifold, 550cc injectors, front mount intercooler with 2 1/2 in intercooler piping and 3' exhaust turbo back and a chipped r32 rb20det ecu that i had re chipped. now i have read on a couple of other sites that i have to swap a few wires over on the ecu harness but i dont know if its true or not. what do you guys think? oh and i did have the chip programed for the mods that i already mentioned. the weird thing is that the only for me to get the car to drive some what normal was if i put the stock rb25det ecu back in. the car is running so s***ty that it ran a 16.04 @ 92mph at the track. it bogged why down out of 1st gear off the light and then slowly creeped back onto a whoping 7psi of boost all the way down the track. can some one please give me some pointers?

[Coolwhip]

by rolling back to your stock ecu and killing it down the track you risked damaging your engine (if not already).

There are differences between the harness modifications for running the R32 RB20 ecu. I've only done it once so can't tell you off the top of my head which and what. Others will advise.

[Cidate]

by rolling back to your stock ecu and killing it down the track you risked damaging your engine (if not already).

There are differences between the harness modifications for running the R32 RB20 ecu. I've only done it once so can't tell you off the top of my head which and what. Others will advise.

I know with nistune's you had to change the pin outs for the rb20 ecus and z32 ecu's to work with the rb25. also had to solder some places if I remember correctly. get on the nistune forums and see if any of those guys can help, I'm sure they can point you in the right direction.

[armygsrcivic]

well even though i drove it down the track the car still runs perfectly fine just until it runs into boost. any idea of why the turbo is really slow on building boost? ill diffently check on the nistune forum for sure. thanks for that advice.

[virus77]

Maybe your wastegate is cracked open slightly and it's spooling slow, check the actuator if its internal.

I'm running a z32 ecu and I had to repin but if I remember correctly the rb20 plugged in, it just can't activate the VTC

[armygsrcivic]

ok well i did some more research on the ecu pinouts for both the RB20DET ECU and the RB25DET and found a few wires that dont match up and was hoping that someone on here can clear some things up for me. so here are my questions....

well i know that on the RB20DET ECU it doesnt have the function to activate VVT so i would have to wire it in somehow. i read on another posting online that all i would have to do is wire the VVT to pin#115 on the RB20 ECU which controls the 02 sensor power wire. does anyone know if this true?

my next question is does anyone know what wire off of the RB25det harness needs to be hooked up to pin# 54 which is the throttle control (idle) switch?

and my last question is, on the RB20DET ECU pinout it shows that pin# 56 goes to the Throttle Sensor Output Signal but on the RB25DET ECU pinout it shows that pin#56 goes to AT/CL/LSD. what wire do i hook up into pin# 56 on the RB20DET ECU if anything?

if there are any other wires that i left out can you please inform me of them?

[armygsrcivic]

oh and i already know about switching the 2 injector wires for 4 and 6

[l0nestar]

What model T3/T4 do you have? You have to repin the harness at the plug. It's a tedious and time consuming task.

[armygsrcivic]

i have a t3/t4 T04E with i believe a 56 trim. im not to certain because im currently deployed in iraq right now so i dont have the turbo in front of me at this time. i know the wiring is time consuming and all but its gotta get done any idea of which wires have to go where?

[armygsrcivic]

bump

[SullivanRacing06]

why not reuse the factory injectors, and install a factory ecu and try running it again, the factory injectors will be enought for that turbo at 5-8 psi,

what do you consider as late spool? 4k?

[armygsrcivic]

well i guess i could re-use the stock injectors and the stock ECU but then that would defeat the purpose of doing the whole turbo swap.(which was to get way more power then stock numbers. and my Tach isnt working in my car cause i still havent changed it out but you can tell that its spinning passed 4-5k before it spools up. probably like 6k

[Carl H]

you need to get a tach that works/reads correctly in the car...else you're flying blind.you also have not mentioned if you have a wideband in the car from above i am going to assume no, so i would guess with the 550cc injectors it is running silly rich.RB series engines run VERY well when rich, unlike other engines which tend to run like crap.The short answer is that you're running so silly rich that while it runs and drives AFRS while driving off boost are probably in the 12's and dive past the 10's when you get into boost due to the 1:1 nature of the stock fpr.you should not be driving around without some form of management on this setup as you're only asking for engine damage to occur.

fitting an rb20 ecu is not hard, add 1 wire and swap 2.downside is you loose vtc but for the money saved instead of going aem or pfc i'd drop a set of rb20 spec cams into the engine with some cam gears and kill off vtc...its lame at high hp/high rpm anyways.

the other option is a z32 ecu...not a bad ecu but several wires need to be swapped and support for only one knock sensor.people will tell you to gang the two knock sensors together but this is quick and dirty to make it work.

yet another option is the VE30DE maxima ecu that they only made for 2 years...it is a direct dropin for the rb25 but requires the use of a daughterboard.JWT can tune this ecu or nistune has support...been a while since i looked into it tbh.