One Stick, Many Ratios
I'm building a single-stick naturally aspirated Civic. I recently read your LX/VTEC swap story (March '05) and was interested in the ZC/Y8 combo with 12.6:1 compression. I have the ZC block and the Y8 head, but I need to know what kind of tuning you were talking about to make it run well. The motor will be in a daily-driven '93 [Civic] EX. I would also like to know a good chip-and-cam combo, but my resources are limited.
Does anybody have faith in the single cam? What about sleeving the ZC? Is knocking it out to 1.8 too drastic? I have the resources and the know-how [to raise displacement], so all I need is a little guidance.
Josh Clark
Via the Internet
How did we know this question would come up? The labeling of the sidebar chart in the Mini Me story (March 2005, p. 65) is somewhat misleading. Instead of calling them engine block and head combinations, we should have said they were piston and head combinations.
Unless it's a single-cam ZC motor (which is basically the JDM version of a D16A6), a single-cam VTEC head will not fit on a ZC. The coolant passages and dowel pin locations aren't located correctly for the head swap to work. If you have a DOHC ZC bottom end with the 7.2cc domed pistons, throw the rods/slugs in a D16 and you'll have a high-comp screamer on the cheap.
When it comes to tuning a motor like that, you are going to need some sort of engine management system that allows for modification of fuel and ignition tables. You'll also want to get your car wideband tuned on a dyno by a competent tuner. A setup such as this is going to need a bit more than general knowledge.
To make it run well, you'll want a cam that will put the dynamic compression in an acceptable range without making the valves hit the pistons or each other. As for sleeving the ZC and going to 1.8, read April's Exhaust Notes to see our sentiments on the matter. We think you'll get a better idea of the repercussions of trying to add that much displacement to a strokey little D. - DB
All the Colors of the Rainbow
I recently had the engine head of my 2000 Civic Si ported and rebuilt with Skunk2 stage 2 cams, sprockets, and valvetrain. I am now looking into raising the compression of my engine with Civic Type-R pistons but have had some trouble purchasing new factory main bearings.
The Honda dealership says the bearings are color-coded and the engine has to be taken apart to find out which ones to order. However, a local shop told me there is a five-digit code that can be accessed by taking off the oil pan. I'm not sure which [method] is correct and I'd hate to spend the day stripping down my engine only to reach a dead end.
Joseph
Via the Internet
We know it may sound lame, but it's worth repeating: Before you do any work like this on your motor, get yourself a service manual for your car. The manual will usually explain where to look for the markings on the crank, main journals and rods that will tell you what size/color bearings you need.
If you are planning to go with OEM bearings, you're going to have to tear the motor down to find the markings necessary to tell you what you need. The other, more popular, option is to use ACL bearings, which are basically all coded green, right in the middle of the sizes. Buy a set of ACLs, Plastigauge them, and if there are any that are outside of tolerance, get the Honda bearings that correspond to what you need. - DB