Ls/vtec tunning

[ls/vtechatch91]

okay.... i have a 91 hatchback and im doing ls/vtec...have everything for the motor..... me and my buddy are actually working on putting it together now..... and i was wondering whats the best thing to do for tuning for ls/vtec... im running a b18a1 block with a pr3 head... pr3 pistons... gsr springs, cams and retainers. itr oil pump and b16 water pump.arp main and rod bolts... all new gaskets etc...

anyways i have a obd-0 harness with a stock pr4 ecu that i know wont work.. i wanted to buy a jumper to convert to obd-1... so i was wondering what would i use that works great and is resonable in price... i dont wanna rev any higher than 8k.... so any help would be great

 

[brian11to1]

the obd0 harness and pr4 will work, but im not sure how its done. something about a external eprom in the ECU. I dont think pr4's had that... anyway you can stay obd0 using a pm6 (90-91 Civic/CRX Si ECU). it will need to be socketed of course. The 90-91 ECU's have the external eprom and that allows it to be socketed. The AC pin is used for VTEC activation. Enough of that... on to OBD1

I converted to obd1. Theres more to converting than just having the ECU and jumper. You will need an obd1 distributor and 4 wire O2 sensor as well. For me, since I wanted to clean up the engine bay, i opted to run obd1 injectors as well. it got rid of my resistor box. I bought a pre made harness for OBD0 to OBD1 to keep shit simple. I used a socketed P28 running at first ITR maps, then we switched it to GSR maps and it ran perfectly fine. My P28 got fucked up somehow, some way so now I'm using a stock OBD1 P30.

 

[ls/vtechatch91]

ya i know about the o2 sensor an dizzy.... so if i use my pr4 ecu now can i run my v-tec off a toggle switch until i get my stuff to convert to obd-1 or should i just wait till i have it all

 

[ls/vtechatch91]

anybody?????