Lightened Flywheel for a D16A8

[Munted]

Hey peoples, I just bought a HD clutch for my 1988 CRX with a D16A8 and I figured I may as well put in a lightened flywheel at the same time. I was reading this thread (http://www.ozhonda.com/forum/showthread.php?t=59215) and it sounds like D series flywheels are interchangeable. Basically I was wondering if someone could confirm this because I saw a Fidanza Lightweight Aluminum Flywheel for Honda Civic D16 (http://cgi.ebay.com/ebaymotors/Fidanza-Aluminum-Flywheel-Honda-Civic-D16-191161-z6-y8_W0QQcmdZViewItemQQ_trksidZp1713Q2em153Q2el1262Q QcategoryZ33732QQihZ021QQitemZ310052345213) on eBay and I'll get it if it fits. Only thing is that it does say it's for SOHC D series engines, no mention of DOHC. Could someone help me out! Thanks.

[SeverAMV]

check if your current flywheel is a 20 spline or 21 spline, d series came with both which can make interchangeability annoying.

with regards to flywheel, if you're getting the 8.5lbs one, i would recommend against it. anything lighter than 12lbs is just making it harder to transfer torque, and the acceleration benefits lose out to the more difficult launches.

[Munted]

Hey thanks heaps for the reply. I should have explained it more fully, on my 1988 CRX I've got a D16A8 engine, I bought this (http://www.ozhonda.com/forum/showthread.php?t=87405) gearbox and HD clutch which is off a 1989 DOHC ZC so I imagine it'd fit fine. But I believe that my original 1988 tranny is different.

From this thread (http://www.d-series.org/forums/showpost.php?p=60187&postcount=13)
"The 1990-1991 clutches are the best stock for torque capacity. They are bigger in diameter than the 1988-1989clutches. Problem is, the 1990-91 pressure plate wont bolt up to a 88-89 flywheel so:
If your tranny is 88, you have to use an 88 clutch disk(small) and an 88-89 flywheel, and pressure plate, because the 88 tranny has a different spline count on the input shaft. Unless you change the input shaft.
If you have an 89-91 tranny, your options are wider. you can use an 88-89 flywheel, and pressure plate and an 89 clutch disk(small) or you can use the 90-91 flywheel, pressure plate and disk(larger). This is the best setup for torque capacity although the smaller package(88-89) would have less rotational mass for slightly quicker response, similar to the effect of a lightened flywheel. Your choice......"

And this thread (http://www.hondahookup.com/forums/showthread.php?t=100454)
Spline count refears to all d series L3 transmissions. First spline count on the input shaft to determain year. 21 splines is 88, you can use an 88 or 89 flywheel(d-series) but have to use a 88 specific clutch. Confused yet? If you have 20 spline count you have 2 options, 1. use and 89 clutch with an 88 or 89 flywheel 2. use a 90 and up clutch with a 90 and up flywheel. I recomend #2 because of the aftermarket trans,flywheel and clutch options are higher.

So you're saying that the first thing is to look at the transmission I just bought and work out the spline count on the input shaft? Then pretty much go from there.

How badly would drivability be effected with a 8.5 pound (3.85kg) flywheel? I don't launch very often, I'm mostly after second and third gear pull but I don't want it to be a pig to drive either.

[SeverAMV]

from my experience, unless you're making a fair bit of power at all revs, the cons outweigh the pros. the cons of the lightweight is that there is less inertia in the flywheel, so it will more likely slow down massively when your clutch clamps down, whereas with a heavier flywheel, it will keep rotating and minimise slowdown and maximise torque transfer. this same thing also occurs with each gearshift. so you'll lose a fair bit of torque transfer inbetween gearshifts. so you know how with most motors, you get a fairly good pull when you ride out the clutch when entering second or third? you'll pretty much lose most of that pull unless your motor makes a fair bit of torque. your best bet would be something around 6kg, which gives the optimal balance between response and torque transfer.

[Munted]

The new transmission going in is a 20 spline and the clutch has an OD of 200mm. All the ones on eBay seem to be 210mm so I imagine they won't fit, bugger I guess.