C4S993

How will you measure the bolt strech when doing the crank's main cap bolts ? I gather just listening for the torque tool 'click' is not good enough ?
Thanks

Ed Hughes

Huh? You can measure stretch on the rod bolts, and that is all that is measured thusly. The crank doesn't have caps, like a V-8 of typical American design. It's held together by the case halves bolting together, that is done by tq.

C4S993

Thanks for the clarification. Then how do you balance the crankshaft with respective to the case/flywheel/damper ? Or is the engine not damper required for haromics ?

Mike J

No damper required - and all other parts are balanced, like the rods, pistons, crank, pulleys, flywheel. The factory balancing is pretty good, but if you do mods, its good to check it all again... the concept of "blueprinting" for american iron is already done by the factory at Porsche.

ReinerFink

The 993 does not have a harmonic dampener pulley (like the 964) as they changed the crankshaft design to make it more stiff.

My machine shop individually balanced all of the crank components. Everything was pretty close except my new flywheel. The LWF was 30g out of balance and they had to drill several holes on the circumference to balance that. 30g sounded like a lot to me, so might be worth checking for folks doing LWF installs.

-reiner

Mike J

Good info - will do that next time! I have made the assumption that the QA is good enough that it did not have to be checked ... thanks!

Cheers,

Mike

C4S993

This discussion is an example of why I continue to renew membership; but how do you measure the crank case-main clearances with plasticgauge strips? Do you button the case up and then reopen case to see the plastigauge tape readings? Or just button case up and cross your fingers?

Mike J

Have you stepped through my engine rebuilding articles on pcarworkshop? It may help.

One procedure is you put the strips on, button it up, and then open it up and check. There have been discussions that this is not a good practice with the theory of crushing the bearing shells should occur only once, and taking good measurements and doing the math is the alternative to check the clearances.

http://www.pcarworkshop.com/index.ph...out_the_series

Cheers,

Mike

C4S993

http://www.pcarworkshop.com/images/1...219_-_0020.JPG
Mike: I looked at your crankcase/rod pic; some looked like captured nut rod caps (others shown look like traditional nuts (rod caps) ?
Thanks

Mike J

There is nothing exotic about the rod bolts other than they are ARP replacements for the stock bolts. Pressed into the end cap and then bolted down - I used a stretch gauge instead of the torque method ...

Cheers,

Mike

C4S993

But I see some rod caps with non arp nuts?

ReinerFink

That is just the bolt head that is showing -- the big end of the rod has the bolt, the 12-pt ARP nuts go pointing toward the skinny end.

-reiner

Ed Hughes

Gee, no affiliation, right?

ReinerFink

Wayne's book (pg 133) states that you should "Apply the 574 sealant to the right-side case half only -- not both case halves."

MikeJ - I see you went in for putting the glue on the left half:



I am leaning toward applying on the left half as well since there are no studs to get in the way. Is there an advantage to putting the sealants on one half or another?

-reiner

Ed Hughes

I'd only use the 574 on the webs around the crank, and Threebond around the perimeter. Henry Schmidt from Supertec has a 4 sealant recommendation for engine assembly. It has worked well for many. Either way, you should only apply a uniform minimal/realistic amount on one side only. More cases leak from having TOO MUCH sealant applied, than any other reason-IMO.