A series Oval port head and Lightened flywheel

[Bartman]

It's gotta be balanced on the crank that it will be used with too. I replaced my clutch, and gave the balancer my flywheel and my new P/plate. He set up my f/wheel on a crank he had, and although it was balanced on my crank, it was 2 grams out on the crank he used. The crank fixing is a little bit under engineered on the a series too. (The pcd is too small, and the bolts aren't a snug enough fit in the holes)

[nzdatman]

although it was balanced on my crank, it was 2 grams out on the crank he used.

how does that happen?
Also agree about the flywheel flange, they should be dowelled if you are going to give it a hard time. My A15 sheared all the flywheel bolts 2.5km into the first stage of a rally once, I was PISSED off.

[Bartman]

If you have all the flywheel bolts 3/4 done up, the flywheel can still rotote fore and aft by a few degrees. Since every crank and flywheel has see differing amounts of misuse and abuse, it's safe to assume that a given flywheel wont seat in exactly the same spot on different crankshafts. I have had a flywheel shake loose (But not break the bolts) only once after a monumental over-rev. The bolt holes had been cleaned out with tap, and degreased with loc-tite primer, then loctited in too.I shit my pants, cos ater the big rev, it stalled. When I tried to start it, it went re-re-duh! Re-re-duh! I thought I'd broken the motor. Turned out the rotor button had walked, and it was all advaned. Fixed that, and it started but had a nasty rattle. My old man said it sounded like a broken crank, But I knew that they were prone to coming loose.
The mating flange of the flywheel gets a bit fretted too. I remachined mine before refiting it. BUt that was on my old blown A14.
I was just discussing this very topic with a guy at 1200.com. it's a harmonics thing. They also have a bad habit of breaking/cracking the front pulley too.
Dowling is the easy fix, although I had to use a carbide tip drill to drill the end of the crank. It was hard as hell. There's also a big thread somewhere at 1200.com where some folk say they ream out their flywheel holes, and go up a size (7/16 maybe?) so that the bolts actually locate the flywheel in ONE place, as well as holding it on. It's pretty commen practise to replace the F/wheel bolts with 12.9 tesile capscrews. Thats I've I've used since my big shakedown. BUT, it does pay to check that the heads of the capscrews dont touch the center of the clutch. I had one Only just touch, and it prevented me geting full clutch plate contact. I never noticed and slippage though, untill I did third gear standstills.

[nzdatman]

yes the crank is quite hard, but we managed to do it with a high speed steel drill bit in a $20 electric drill from supercheap auto and dowel it using tension pins. All this was done with the car on the trailer in the dark outside out motel room. We got some secondhand bolts from some locals and were away laughing, it has been good as gold ever since. The harmonics are a problem I have heard of people using dampers on the front pulley I would look at that if I was going to stay with the A.

[cheater_5]

the last lightened flywheel i owned had the holes/bolt holes bored out to accept much larger bolts.
Just thought id put that out there

[150Y]

Here's more pics of Head!






As I said I got it for the double springs, I got new springs with my cam from Reg Cook, This is how I got the head and I haven't done anything to it!

[150Y]

Gidday, Flywheel is gone to another project!