Switch to PR4 or stick w/ PM6?

I just picked up a free PR4 ECU from a '89 Teg... was wondering w/ my list of mods, if it would be better to use that ECU, or stay w/ the PM6 that I already have in the car...

What mods do you have?

Intake, short ram (behind headlight) MPFI swap w/ p&p head, 3-angle valves, A6 cam on B2 block/head. Running HF tranny (I love this thing, w/ the long ass gears)

I'd say just stick with the PM6...unless your motor requires more gas that you might risk running lean because of your mild port and cams, then run try the PR4. Do you have an adjustable fuel pressure regulator or upgraded fuel pump? Header?

Or do a test run and check your plugs and see...then decide. Tough to say, especially when you don't have a tuneable ecu.

that motor isn't staying in the car.. I'm doing a ZC swap eventually

right now, it runs a lil rich, but that's b/c of the timing problme I have right now

I thought the PR4 ecu was from the 90-91 teg (b18a1). So you'd run really rich if you use that ecu. And if you are using an ecu from a 89 teg (d16a1) then you won't see any difference anyway. Just stick with the pm6...

nah, PG6 is the B18 ECU... all those were gone, and it would have been more profitable to walk out w/ that one (junk yard gave me any ECU I wanted in exchange for helping a guy out.)

'Sok tho, I just got a D16A1, and I already have the one that goes in the '86... meaning that I'm going to do the swap that everyone says is soooo hard and should never be done... lol.

Why? You won't make any more power than if you had a d16a6 (which you sorta already do a6 cam on b2 block. (fyi - supposedly 90-91 si had 2 more hp than 88-89 due to cam with the same ecu). So you really want 2 cams with no power and some fabbed up bolt holding it all together? :lol:
GL, dude...

That's the thing.. it's not actually that hard to put in.. there is only one bolt that doesn't line up that actually needs to be there, and you just drill the block flange for the bottom starter bolt, or thread the hole in the tranny and use a shorter bolt... other than that, everything else (including the lil lineup pins) lines up fine.. the front mount can either be shaved (stock mount) or the 'teg mount can be flipped over and shimmed, and the bolts have to be pressed out and real bolts used.

Wiring is easy as well, use an 89 Si harness, for the engine, I think you have to move three wires.. I actually have a diagram for it somewhere, b/c I was going to do this w/ my CRX to get it running when I didn't have a license.. but I ended up deciding not to fix the body, and it's sitting in the barn right now, being slowly stripped.

As far as power, it's not a big deal to lose 2 hp or even 5 hp, b/c I gain alot more tunability w/ 2 cams, and I'm either going to go w/ 10:1 comp or 8.5:1 and a small booster. (IHI RHB5)


And I'm thinking about using the A6/B2 combo on my go-kart lol

the PR4 is upside down... what the hell... the ECU light is on the other side.. i forgot teh wiring comes in from the wrong side on the 'teg. dammit. that will make it a pain, I'll have to drill another hole in the floor pan cover for that swap lol

Try again.

PR4 is a 90-91 integra ecu
PG6 is a 88-89 integra ecu

Don't believe me? http://hondaswap.com/reference-materials/honda-ecu-list-29129/

But should you use that ecu you have? No. From the sounds of it you have a d16a1 ecu, the pr4 is not backwards, Ive had one on my desk for the past 6 months if you need me to take a picture of it for you. Run the correct ecu for your motor. Just because it has richer fuel maps doesnt mean it will manage your motor better.

Try again.

PR4 is a 90-91 integra ecu
PG6 is a 88-89 integra ecu

Don't believe me? http://hondaswap.com/reference-materials/honda-ecu-list-29129/

But should you use that ecu you have? No. From the sounds of it you have a d16a1 ecu, the pr4 is not backwards, Ive had one on my desk for the past 6 months if you need me to take a picture of it for you. Run the correct ecu for your motor. Just because it has richer fuel maps doesnt mean it will manage your motor better.
Didn't say it would run better, I'm ALREADY running rich.. I turned it down b/c I was running rich already... and I plugged it in... it won't even start the car.. main relay doesn't even click. so that solves that issue, but thanks for correcting me on the ECU coding.

It IS a PR4 ECU... and it's not exactly backwards, but it's up-side down.. i.e. the light is on the other side when it's bolted in (bottom as you're looking at it.) But when I pulled it out of the car, the wires were on the other side from where they would be in my Civic.

So that would make it a B18 ECU right? I didn't check the date code on it, but I will in the morning. Should the B18 ECU plug right into my wiring harness?

Should the B18 ECU plug right into my wiring harness?Yes it will plug right in.

K, well, it's a B18 ECU then.. and it's not what I wanted, but it's still worthwhile for free, I'll just sell it.

I thought the PR4 ecu was from the 90-91 teg (b18a1).

PR4 is a 90-91 integra ecu

So I was right... thanks Hybrid...