Somebody Blew It

daveo wrote:

SWest wrote:

I've tried but no go. I'd be careful not to thread the studs in too far. I'd test with the barrels and head to be sure you'll have enough threads for the top hat nuts. 

Steve

 

CS900K studs were installed in the 82 motor.  Each cylinder stud firmly seats against the hole bottom when tightened as specified.

www.aperaceparts.com/tech/cs10mm.html

You need to be wary when fitting the APE studs.
Just winding them in and torquing can result in too little threads showing for the head nuts.
You need to measure the height of the stock studs or the height of the head and block stack and set the APE ones to the correct height .
Many times the studs will achieve the correct height before they bottom out in the cases so need to set in with red loctite and left overnight to cure..
I always set the stud heights dry, mark the stud with tape at the case level then remove and refit with red loctite.

When I did mine I compared the stock studs with the APE (American Performance Engineering) studs before I used a tap to clean the threads. I didn't cut further. When I installed the head there was just enough threads showing to bolt down the head. I used the stock top hat nuts and they compressed the gaskets for a good bight and when I removed them later they looked normal. Whew 
Steve

Thanks, I will double check that when installing the cylinder studs in this motor.  What amount of stud engagement is considered ideal for the nuts?
 
Seems like there was about 1/2" of threaded stud length available for the nuts when fitting the head last time. 

 

Minimum 10mm .
As a rule of thumb for any thread you need at least the equivalent of the width of the thread engaged in the nut.
So 10mm bolt = 10mm of thread and a 6mm bolt = 6mm thread etc.

The APE top hat nuts are taller so I assume it was to make up for more longer studs. 
Steve

SWest wrote:

The APE top hat nuts are taller so I assume it was to make up for more longer studs. 

Steve

Yes! They are taller so they don't top out on the studs due to reduced deck heights as the result of skimmed heads and milled blocks etc.

This measurement was easily obtained, and no side-to-side movement of the crankshaft could be detected. 
Newly installed welded crank thrust bearing clearance:

Speaking of tight tolerances...  






...they're everywhere!




And where the weld passes...

daveo wrote:

Speaking of tight tolerances...  

...they're everywhere


And where the weld passes...

That doesn't matter as long as it clears.
2mm is a country mile in engineering terms.

This is the front cam chain guide from a J motor.
Should I feel confident reusing it?







Former guide:
photos.app.goo.gl/zYhL3D86nTu8CJE98




 

I wouldn't 

SWest wrote:

I wouldn't 

+1