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Hey Guy

My engine build was humming along great until I bolted the heads on.  The head studs are sticking so far above the nut,  a few of the rockers are hitting the bolts.  It looks to me that these studs are longer than stock.  My case has the 8mm case savers and I checked that the studs are bottoming out.  They are about 25mm into the case.  I have all studs in the their right place so I can't understand why they protruding so much.  I have attached a few pictures.  Any thoughts or comments would be welcomed.

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Let me preface this comment with the caveat that I'm am in no way an engine builder nor have I played one on tv. I have stayed at a Holiday Inn but it's been a long time.

If they are bottomed out in the case and they are sticking up this much then I'd just get shorter case studs. There could be a couple reasons: They may have been packaged wrong and they're longer than expected, the person you ordered them from gave you the wrong size, or maybe the case was drilled shallower than your previous one. either way I'd just get shorter studs.

Last edited by Robert M

I've had to do it on an engine when the heads were flycut for more compression. If there's thread on both sides of all the head nuts (the nuts are not bottoming out on the unthreaded parts of the studs before the heads are torqued down) you could just shorten them. Leave 2-3 full threads outside of the nuts. You'll have to clean up the ends after cutting, and that's easier if there's already a thread chaser thingie (I'm so technical) on the threaded part. File or grind the end of the stud smooth, remove the thread chaser, and then check that a nut goes on easily and there's no metal bits left on the stud. Al

ALB posted:

I've had to do it on an engine when the heads were flycut for more compression. If there's thread on both sides of all the head nuts (the nuts are not bottoming out on the unthreaded parts of the studs before the heads are torqued down) you could just shorten them. Leave 2-3 full threads outside of the nuts. You'll have to clean up the ends after cutting, and that's easier if there's already a thread chaser thingie (I'm so technical) on the threaded part. File or grind the end of the stud smooth, remove the thread chaser, and then check that a nut goes on easily and there's no metal bits left on the stud. Al

Al,

Won't you lose the slot where the allen wrench goes in to tighten/remove the case studs if he cuts them shorter? Or will 2 or 3 threads above the nut leave enough room to put on another nut for removing the studs?

Robert M posted:
ALB posted:

I've had to do it on an engine when the heads were flycut for more compression. If there's thread on both sides of all the head nuts (the nuts are not bottoming out on the unthreaded parts of the studs before the heads are torqued down) you could just shorten them. Leave 2-3 full threads outside of the nuts. You'll have to clean up the ends after cutting, and that's easier if there's already a thread chaser thingie (I'm so technical) on the threaded part. File or grind the end of the stud smooth, remove the thread chaser, and then check that a nut goes on easily and there's no metal bits left on the stud. Al

Al,

Won't you lose the slot where the allen wrench goes in to tighten/remove the case studs if he cuts them shorter? Or will 2 or 3 threads above the nut leave enough room to put on another nut for removing the studs?

I've never seen head studs with machined ends for an allen wrench, Robert. I've always had to double nut the studs to remove and install them. And I've never seen studs so long that (even when shortened) that there wasn't enough thread area to double nut them.

Bobby D posted:

Guys

I think I got the studs that are 1/2 inch longer.  The longest ones on the push rod side of the heads are 9.5 inches long.  I don't know what is the standard length. How much of the threads should you see above the case savers if the studs are bottomed out?

I thought the threads should just about bottom out on the case end, but I could be wrong. I have some 10mm studs (taken off an engine years ago) in a box in the garage that are 8" long, but I don't remember exactly where they are from. I have some 8mm head studs on a stroker engine (over .200" shims under the cylinders) on the bench in the garage and the 4 in the rocker box look to be about 9 1/2" long (if I get a chance later I'll remove the head and check; it's only mocked up at the moment), but to be honest I don't remember where they were from. I think they are stock VW studs, but it's been so long... 

Robert M posted:

Thank you Al. Hence my warning that I'm not a mechanic nor do I pretend to be one. However, I am doing what I can to learn. 

Don't worry Robert; I'll bet you know a heck of a lot more than when you first bought your Speedster. Think of all you've learned since that day (how long has it been?), and give yourself a pat on the back.

Alan Merklin posted:

Dumb question,  did the threaded rods have longer threads on one end than the other?

Not that I'm aware of, Alan. The head studs I've seen have always had about the same amount of threads on each end, but then I don't have any experience with aftermarket studs.

Bobby D posted:

Hey ALB

I am having a great time with the build.  You are right I am learning a lot.  I have never built an engine before, so this is great.  I am lucky to have father-in-law that is a master mechanic and access to you guys.  My father-in-law is a little rusty on these old vw type motors.

Glad to hear you got the head studs cut, Bobby. As you've probably figured out, if you leave them too long in the rocker box they interfere with the rockers, and the top 2 middle studs can hit the intake manifolds if left too long as well.

Learning stuff is always a good thing, and the more you know about your car the better. There are some things with these engines that are a little different than normal watercooled stuff, so as long as your father-in-law is willing to learn as well, it sounds like you're in good hands. Any time you've got questions, don't be afraid to ask; someone will jump in and help.

Yoda out- but back you know I will be!

next problem to solve is rocker arm geometry.  I have the scat forged 1.25 rockers.  The swiping of feet across the lash cap is to high.  I did the dry erase test on the lash cap.  The swipe is above the mid line on the upper half of the lash cap.  It seems to me that the rocker needs to be shimmed up to get the sweep lower on the cap.  An of course I will need to work with the push rod length to make sure oil can pass through the channel on the adjusting screw.  I am thinking right.  I don't see how just changing the push rod length would affect the swipe if the fulcrum point doesn't change.  A longer or short push rod would result in a longer or shorter adjustment to the foot adjuster the push rod side.

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