ZC Swap Questions.

[QMaze]

I have decided to do a ZC swap once my current stock motor packs it in. Question is since I have decided to keep my SI completely stock (was contemplating EF9 conversions but everyones doing that) the only thing I would like to do is just give a little of power so ZC would be the answer.

My 90 Civic SI is getting a bit tired and I want the cheapest DOHC solution. From reading the swap articles I have come to the 2nd Gen ZC DOHC but I am a bit confused as to the transmissions. It is recommended to use the SI transmission, why is that? Is the ZC tranny not the same? Reason for my concern is I'm pretty sure my synchros are worn out on 3rd, grinds when shifting at higher rpm's. Does it take special tools and could I possible use the guts out of the ZC, sort of combine the two tranny's to make one good one and use the SI as the shell? Or would that require a transmission shop because I'm thinking of thrust washers or shimming, not a transmission person.

I have a list in my head that I think I will need to do such a swap, please comment.

JDM ZC Hood - Clearance for the DOHC
2nd GEN ZC
Stock Civic SI tranny - to eliminate the half shaft and use my fairly new axles.
Pressure Plate & Clutch - Anything special required to mate the SI to ZC?

Shouldn't require any additional or modification to the wiring, correct?

That should do it.

Thanks

 

[Drake]

The SI tranny is better for crusing down the highway. If you do use a ZC be ready for 3500 - 4000 rpms at 70 or so mph. Closer ratio trannies get up to speed faster but cap out sooner on top end. I my self opted for the ZC tranny when I did my swap.

 

[QMaze]

Thanks everyone, jlicrx has graciously explained my options plus the hybrid SI/ZC transmission solution.