Looks good, the injector cut outs make it look like an N42 head.  

I learned the hard way about that "one size fits all" lapping compound.  Captain Obvious offered me some of the rough and the finer but I marched on with that crap.  I jimmy rigged a suction cup off the lapping tool to my variable speed drill, that helped a lot.  Seems like I used a male 3/8" air coupler in the drill and slid the suction cup over that?  After using it straight I started doing "laps" with a little water mixed in until it made a nice steady and smooth sound.

i really liked the old valve-cover intake plenum :-(

bring it back! bring it back! bring it baaaaaaaaaaaaaaaack!

Edited April 17, 20177 yr by Careless

1 hour ago, siteunseen said:

I learned the hard way about that "one size fits all" lapping compound.  Captain Obvious offered me some of the rough and the finer but I marched on with that crap.

Yeah, I'm not a fan of that water based multi-grit stuff. My description would be that it's for people who are in a hurry and are willing to sacrifice some surface finish quality for speed of getting the job done. Since the only kind of that work I do is for myself, I'd rather use a much finer compound even though it takes longer. Takes longer, but the finish is better.

However, that said... Someone in the business could easily convince me that it doesn't matter anymore after that valve has opened and closed a thousand times though.  

Valve cover intake is wall art at this point, but might be re - utilized later.

Haven't done much of any valve lapping , so this is kind of new for me. Using a Permatex stuff Jegs sells and used my cordless drill .
Just wanted to get a uniform seat surface and to check for discrepancies .
Still need to do more work on the injector notched. I thought I had them big enough- but could see I didn't once intake was bolted up .



Sent from my iPhone using Classic Zcar Club mobile

I've got a lifetime supply of this stuff and would be happy to send you some if you don't want to buy a tub yourself:

Pulled that pic from this thread where we were talking about valve lapping:
http://www.classiczcars.com/topic/50909-72-240z-rebuild/?page=8#comment-475857

 

Sorry Captain,

didnt mean to not say thank you anyway.

Valves looked great and cleaned up nice- the piston bore was something else though :-0

looks like #1 didn't get clearances correctly on the notching so it cleared itself. Tough motors these are!

needless to say I opened that up a little. 

Pay no concern to the divot in the middle of the piston . Just hit the piston stop too many times timing my cam

Nice. Was that valve dent caused during running, or during testing?

And either way, I'd be worried about valve (lip or stem) might be bent after that... You sure that one was OK?

That engine has many hard miles on it so if it was broke I would know it. It lapped in like the rest .
It's funny that I got a lot of crap for making my notches so big on my last block - but I guess I went to small here, and off target.
I didn't see this until after my head was reassembled after lapping valves. I'm going to run it !


Sent from my iPhone using Classic Zcar Club mobile

I'd do a compression check, just to put my mind at ease.

I've been running this engine for a while, and I've done several compression checks - so I would be surprised to find something now. I am curious what numbers I will come up with at 10:5:1 !!


Sent from my iPhone using Classic Zcar Club mobile

Cool! If it lapped in like all the rest, then I would assume nothing is bent.

That relief doesn't look "too big" to me. It just looks a "little off" in position.   In any event, sounds like it's all academic at this point!

It will have to be - not turning back now. Getting close




Sent from my iPhone using Classic Zcar Club mobile