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Well it seems that you already know that the pm6 is not the correct ecu for the dohc zc. . . . it will run it though but not as well as the one for the ZC.. . . . .If you were going to pay to get the ecu modded why didnt you just get the dohc map dumped on it. . . . .the 9 grand rev limit is not going to do much for you except give you the opportunity to see your rods quicker than any person taking the engine apart by hand to get the rods out.... yeah it works... .its not 100 percent ideal but it will work.... although not quite right either for it. . . . .a pr4 has a little richer map... . . . and is better suited still for a dohc engine.. . . . . .might want to look to see if you have one of those laying around.
 

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Discussion Starter · #3 ·
yeah..... the guy i am getting it from said that it would work and run damn good. he said that it would run better than the one i have now...?????

but i am trading it for a 88 hf that the guy has a FULLY!!!!!!! built b16a
thats is built to withstand 12000. and a 250 shot of n02

so that will be a really mean rex if i say my self!!!!!!
but uhh i called someone else that has been into this honda scene since he was 16 and now he is like 28 he told me that it would work also, but the 9000 rev limiter wont do much but its the fuel and air bars maps that will do the big difference!!!!!!!!!!!!

now i am just wondering if they say it will work as good as they say it will
the guy i am trading the rex to is a 5 time honda mechanic and does INSANE swaps and motor builds...... if i can get pics of the b16 ill post them up!!!!1
 

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Discussion Starter · #5 ·
the cams are ment for 12k but he took it up to 10 for safty.... he has stage 3 cams and bad a$$ stainless valves. titanium springs and retainers. and arp rod and mains studs and bolts. then he has rods and pistons.... its a mean motor when he had it in his 95 coupe it ran a mid 12 all motor with out the n02. but the car was striped of every thing but the dash and seats
 

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Discussion Starter · #6 ·
i was meaning that it could go up to 12k but it ran out of cam at around 10-5 it was a screaming machine when it was in his coupe....!!!!!! sorry didnt finish all i was going to put im really tired and an not thinking straight
 

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I wish I could find where I read it, but yes ,the PM6 will run the DOHC ZC.

If I recall correctly:
PM7 - ideal
PG7 - slight power increase
PM6 - slight fuel econ increase

Now I'm going to be hunting the dang web for where i read that...
*edit* found it:
http://fourthgenhatch.net/zc.html#ZC

ECU
Integra "PG7" (More power) or
'88-'91 Civic/CRX Si "PM6" (Better MPG) or
ZC "PM7" (BEST!)
edit to add som other helpfull URLS for the ZC ppl:
TheZCResource.com
D-series.org

Both are excellent sites for ZC info.
 

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mithuth said:
I wish I could find where I read it, but yes ,the PM6 will run the DOHC ZC.

If I recall correctly:
PM7 - ideal
PG7 - slight power increase
PM6 - slight fuel econ increase

Now I'm going to be hunting the dang web for where i read that...
*edit* found it:
http://fourthgenhatch.net/zc.html#ZC

ECU
Integra "PG7" (More power) or
'88-'91 Civic/CRX Si "PM6" (Better MPG) or
ZC "PM7" (BEST!)
edit to add som other helpfull URLS for the ZC ppl:
TheZCResource.com
D-series.org

Both are excellent sites for ZC info.
Definitely not right... when I ran a PM6 on a ZC, it blew black smoke, and drank gas faster than it should (ran way too rich)
When I swapped up to a PG7, it ran better, but was still rich.
The PM7 is the correct ECU, and will show the best results.
 

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Cool, thanks for the heads up.

My ZC swap came with a PG7, but I've been watching for a PM7.

On the joking side: What do you mean it's false... I read it on the internet, it HAS to be true! *grins*
 

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I think you could run the ZC fine on a properly chipped PM6. If it's chipped and running a map for the ZC, it could run it fine, it's just not going to do it stock. If you can't find a PM7, chipping/tuning would be the best alternative. Hell, even if you had one, tuning it would be the best way to make the most of your motor.
 

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Discussion Starter · #12 ·
yeah my stock is 7500 but i wanna take it to 8000 if i can..... my jdm pm7 ecu is not cutting it i need more of somthing......
so i asked my friend if he knew of any chiped ecus and he told me that he had the pm6 ecu chipped and he said its tuned for ANY 1.6 dohc motor :D so if it will run it and then ill trade for my other rex.... is that a good trade the rex dose not have a motor or any thing its fully striped he is making a sleeper out of it... stock looking as possible
 

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90crxhf_w/ZC said:
yeah my stock is 7500 but i wanna take it to 8000 if i can....
Without some internal work done, i wouldn't take it to 8k. There is a reason Honda put the limit on it at 7500+/- .
Just because you raise the rev limit does not mean you are getting more power, but putting uneeded stress on the motor.
You don't make that much power anyway past 6500 or so, there is no point in raising the rev limit and risking blwong the hell out of that motor.

But go ahead and tell us how it works out for you. :?
 

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Why don't you just chipped your existing ECU and get your car dyno tuned? It would be cheaper in the long run for you and you would see the best gains. Don't take it more then what HONDA set there factory rev limiter too. Your engine is NOT, repeat NOT designed to go to 8000rpm and you would just shorten the life of the engine. You might even throw a rod if the engine is showing it's age (17-18 years old now). We did it to a SOHC ZC before we knew anything about hondas. We had one set to 8500rpm. Drove it there all the time. Threw a rod on the highway after 5-6 weeks. Not fun when you never changed an engine before.

Get your car tuned or keep the stock ecu on your STOCK engine. Once you get mods then I would get it tuned. PS: Intake/Header/Exhaust aren't valid enough for a tune. Maybe do a head gasket and up the compression by shaving the head, then get it tuned.
 

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Max power is around 6800rpms, so yea, running it up to 8000 is pointless and just adding stress on an already old motor. I don't even take my cars to redline... there's no gain.

Upping the redline with out upgrading internals is bad bad, not cool bad
 

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yeah my stock is 7500 but i wanna take it to 8000 if i can.....
This is why there is a shortage of thee DOHC ZC engines. . .. Leae your rev limiter where it is at untill you have a reson to raise it. .

You will be happier in the end. .

IF your in the neighborhood. . . you can visit my hall of shame. . or mangled pistons and broken rods. .

I speak to help. . .

Chris
 

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rex2nr said:
Max power is around 6800rpms, so yea, running it up to 8000 is pointless and just adding stress on an already old motor. I don't even take my cars to redline... there's no gain.

Upping the redline with out upgrading internals is bad bad, not cool bad
toxiclows said:
This is why there is a shortage of the DOHC ZC engines. . .. Leave your rev limiter where it is at untill you have a reason to raise it. .
Both points exactly, :)b
Raising the rev limit on a motor that has no internal work done to it is pointless. You're not gaining any more power and just putting uneeded stress, and more wear and tear on it.
 
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