my buddy just got a 91 si rex for free, all it needs is some fenders, a hood and bumper. the rest of teh car is in great shape and no frame damage or rust. he ordered a d15b longblock for like 450 shipped and wants me to put it in for him. i'm not an obdo d series guru by any means, so i need a little help.

questions:

1) can i use the a6 dizzy on the d15?
2) what is the best/most economical way to hook up vtec, should i get a ps9 ecu?
3) that's all i can think of for now :P

 

1.) nope
2.) rpm activated switch(but this is only economical, its stupid to run without the correct fuel and ignition maps for the vtec lobes.

 

i'm perfectly capable of chipping the ecu with the right .bin for the engine, i just need to know my obd0 vtec ecu options, i never planned on running a switch or afc. and what dizzy do i need, one for a d15? what's the difference? will i run in to any other problems other than wiring up vtec and the dizzy?

 

well u asked for cheapest answer to number 2



i personelly am going to end up using one of two things for vtec engagement on my obd-0 harness with the d15b vtec head.

1.) a chipped ECU(as u said)
2.) the obd-0 JDM b16 ECU. I think its called the pr4(forgive me, the Honda alphanumeric soup is one thing i dont always keep fresh in my head outside the D series family)

the distributer will have to remain a OBD-0 distributer, you might be able to modify the vtec z6 or VX model distributer to run obd-0 clips.

this is where the problem with the lack of pre91 "vtec" SOHC parts exsists.

i may just end up doing an obdI conversion...

let me go mess around and see what i can find exactly with my z6 distributer and my crx.. ill get back to you in abour 15mins.

 

the current engine is an a6, maybe i should have said that, does this mean it's not a 91? i'm just going off what he told me, i'm by no means a crx data base :P what's this i see about the ps9 ecu's with one wire vtec hook up? and since i'll be using the harness that's currently in the car, why would i have a problem with using the current dizzy if it's obd0, and i use an obd0 ecu? or is the obdo vtec dizzy different?

 

just went outside, i say the best bet is to use the z6 distributer and use the plugs for the OBD-0.

there are the same number of wires and i beleive they are the same color, .. you will have to get the wiring diagrams handy for this however. (as im sure you already know)

thanks for asking this question, as until just now when i went out and took a look i was wondering about this very instance myself for my car/motor plans.

hope it works out for you!

 

whoa we are replying to fast to eahc other.


you have to use a vtec distributer with a vtec head.
and the problem is that a an USDM obd-0 SOHC vtec distributer doesnt exsist.

btw if its an si its a d16a6.

 

ok, i thought you kept referring to 'the z6 dizzy' b/c you thought that's what was in there (once again, i don't know ---- about rex's), so i need to pick up an obd1 z6 dizzy, splice the obd0 plugs on to it off of the obd0 a6 dizzy and plug it right up? now, for vtec ecu :P

 

ahh but getting a USDM obd-0 vtec ECU that does not exsist is impossible.

enter the EF blues...

 

what is a ps9