zc swap

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ok so know another question which is better to go with zc sohc or a zc dohc?? Is there alot more to putting in the dohc????

https://hondaswap.com/auto-multi-media/zc-dohc-1991-hatchback-transplant-epilog-515235/

I used the stock Si tranny as it had a recent rebuild on it - runs good. Car runs much better than the D16A6 did.

If doing it today, I would have put a set of ARP studs and ran a 0.031 head gasket for 10.5:1 compression. May do that in time anyway. Of course, that will also require a ECU change and tune.
 
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ok so know another question which is better to go with zc sohc or a zc dohc?? Is there alot more to putting in the dohc????
DOHC ZC is much better than SOHC ZC - bolts right in - use the Si engine harness and you have one minor change to make at the distributor
 
also one more thing can i use a zc trans?? or should I stick with the si trans which is better
you could use the ZC transmission but since you already have the Si transmission, just use it - with the Si, it will have quicker acceleration than with the ZC due to the shorter Si final drive
 
Quoting myself because this makes no friggin sense and I still want it addressed. Seems illogical to run a SOHC Engine with a DOHC ECU.
since the OBD2 SOHC ZC has the same horsepower as the DOHC D16A1, the engines are the same size and the compression ratios are about the same, they should require about the same amount of fuel in order to make that horsepower - the ECU will make minor adjustments for the amount of fuel it actually supplies based on readings from the O2 sensor - the ECU doesn't know if the engine is SOHC or DOHC
 
ok so dohc motor is the way to go. What change will I have to make to the dist??
SiZCwiring1.jpg

SiZCwiring2.jpg
 
Quoting myself because this makes no friggin sense and I still want it addressed. Seems illogical to run a SOHC Engine with a DOHC ECU.
It's not about SOHC or DOHC it's about how well it breathes, cam timing, compression ratio - essentially, horsepower.
 
ok so dohc motor is the way to go. What change will I have to make to the dist??
You don't have the engine yet it seems. If goint the route of the DOHC ZC, suggest you update the car to OBD1 as it opens many possibilities for future growth and performance enhancements - wiring at the ECU is a ~$50 jumper plug and it's done.
 
im seriously thinking about doing this swap now... in my 88 crx si... though i have found a good d16z6 for sale
 
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the DOHC ZC I put in mine was $795 delivered and needed a $30 flywheel and $125 distributor. I had a full rebuild done to it - machine shop said it was in great shape - so, if I wanted a stock engine that's all it would cost.

Did you read the link I posted on the one I did? That should answer many of your questions.
 
hell yeah, and thats definitely where i'll be going for info if i decide to use a zc motor... thats pretty complete man
 
so to change to obd1 is a jumper wire?? also is the zc fly wheel the same as the stock si fly wheel. looking to upgrade to a lighter fly wheel and stronger clutch. yeah I have not bought the motor yet looking for the direction I want to go.
 
so to change to obd1 is a jumper wire?? also is the zc fly wheel the same as the stock si fly wheel. looking to upgrade to a lighter fly wheel and stronger clutch. yeah I have not bought the motor yet looking for the direction I want to go.
yes, the ZC uses the same flywheel and clutch assembly as the Si
 
thanks for all your help. was thinking about a turbo what can a stock zc dohc hold???
depends on how long you want it to last and how it is tuned - i wouldn't go over about 10psi boost which will give it around 200whp, with a good tune and quality parts - the tune is the key to making it last - some people have made over 300whp on a stock DOHC ZC but they didn't last very long
 
so to change to obd1 is a jumper wire?? also is the zc fly wheel the same as the stock si fly wheel. looking to upgrade to a lighter fly wheel and stronger clutch. yeah I have not bought the motor yet looking for the direction I want to go.
Wiring and ECU change. Save yourself some money and just have the stock flywheel balanced and lightened (if the starter ring gear is in good shape) and put a clutch kit in it.
 
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