Need help properly aligining crank shaft, cam and distributor. Help please!

[cygnusx1]

The key at 12:00, OR the line on the ZERO at the crank pulley should both be really close to TDC. Close enough. They don't move relative to each other...unless the crank pulley rubber damper ring has failed.

Edited April 26, 2012 by cygnusx1

[Zed Head]

Is it off yet? My suggestion for removing the head with manifolds attached was short on details. Don't forget to build a wedge for the timing chain, unless you'll be taking the front cover off again.

[cycloid]

Hello.

Yes! I was able to take the head off. there was no problems. No broken or stripped bolts.

I can see the marks on the pistons where the valves hit. It doesnt appear to have caused any major damage.

The cylinder walls look very clean. there is no rust and no scratch marks.

Ill post a video later.

[Zed Head]

Leaving the exhaust manifold hooked up - that's another way to do it...

It might be just the camera angle but those look like flat top pistons and the exhaust manifold looks like it has the later ZX style diamond shape. Do the exhaust ports in the head have liners? Does the head say P79 or P90 on the passenger side, above the 1 and 2 spark plug holes? Does the block have F54 molded in to it down by the driver's side motor mount? You might have a ZX motor in your 1978 Z. Might be important for parts.

[cycloid]

Hello.

the block and head say N42. the exhaust manifold says N47

here is the manifold from a different angle.

[cycloid]

[Zed Head]

The N42 block came in the 1978 cars,but the factory head was an N47, same as the N42 but with exhaust liners. The pistons should be dished, but those in your pictures and video are definitely flat-tops. So you don't have a stock 1978 setup. If the head has not been modified you'll have around 9.8 compression ratio. Depending on where your timing was set and some other considerations, you might be close to the detonation threshold. Maybe that timing chain noise was engine knocking? Who knows, different people get different results. Some people have no problems with higher CR, some people have to back off the timing. Flat-tops and an N42 head is not an uncommon combination.

Anyway, your engine is not stock for 1978. Somebody has been in there messing around before you got it. Good luck with it.

[cycloid]

Thats a real bummer to hear. I thought It was original for the most part. I have a huge folder with all the receipts for the work it has had done on it.

What you recommend personally? I dont want to blow up my engine. Should I get the proper pistons?

[Zed Head]

It's not a huge deal. Just something to consider when buying parts, piecing things back together, making decisions or tuning it afterward. You just have a non-stock setup so the factory specs. might not work the best. If you're not in to the tuning and modifying side of things, it might not be a good situation for you. There are several members of this forum who run the N42/flat-top piston combination. Start another thread with "N42 head and flat-top pistons" in the title and you'll probably get lots of suggestions. I've only tuned the stock combinations so can't speak with authority on your combination.

I would dig through the receipts though and see what's been done. Might be some more interesting stuff in there.

Edited April 28, 2012 by Zed Head