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View Full Version : Yeah, I know it's not a "ZC"...LOL


turbo joe
01-13-2004, 12:25 AM
...but it seemed that this was the most apporopriate place to ask a DOHC question...besides, you can't swap a real "ZC" legally in CA.

I just got done swapping an '88 D16A1 shortblock into my '87 CRX that has (had...blew a rod last week) an '87 -A1 motor in it. I couldn't find a decent early shortblock. I was sweating a little about whether it would work or not, because Honda lists different headgaskets for them. I checked around a few places and everyone (HKS, Fel-Pro and a couple other places) lists the same gasket for early and late D16A1 motors...HKS shows the same for both, plus the ZC.

Anyways...I just used the crank gear, guides and pulley from the newer block and stuck it in...runs nice. They run much smoother with all four rods in them. :)

I have no clue about the compression ratio, though. As someone posted here, the late pistons (supposedly the same as the ZC) have a much bigger dome...but they all (early and late D16A1) are supposed to have the same C/R (9.5:1). The early and late chambers look to be similar...how does that work? It doesn't ping on 87...LOL...so far... :?

It's not a race car (I have one of those <====see avatar), it's my daily driver, so I didn't get into cc'ing it or anything. Anyone have a clue what the C/R is or should be?

KaBlammyman
01-13-2004, 09:03 PM
browntop d16A1 CR = 9.3:1
blacktop d16A1 CR = 9.5:1
ZC (brown and blacktop) CR = 9.5:1

turbo joe
01-13-2004, 10:37 PM
The dome looked to be pretty big, but I'm really not that familiar with them.

Thanks for your help!

strudel
01-13-2004, 10:39 PM
Try this site, just for the 1st gen Teg and do some searching. Specs are on the home pagehttp://www.g1teg.org/phpbb/

The difference in compression is in the combustion chamber of the head.

86 -87 brown top has square intake and vaccum advance w/external coil, flat top piston and beefier rods.

88-89 black top has round intake and electronic advance w/internal coil, lighter rods and domed pistons.

I guess if it runs good and you have no problems you should be happy and just say "thank god it works"

redteg87
01-14-2004, 10:37 PM
Yeah, we'll help you on g1teg.org

The blocks should be identical. The headgaskets may be different because of differences in the 86-7 and 88-9 heads.