Question for RDF

I've never welded aluminum successfully, but I used to build air cooled VW engines professionally.

The last engine I built has a 2-stage 2 barrel Holly carb, and a stage-4 cam. It would tach 10,000 rpm and it twisted the center out of three clutches in 125 miles. I still have it and I'm not currently using it but it's not for sale.

You don't need a welder, you need another engine case. If you're going for a stroked block whether you're using stock 85.5 jugs or boring the case for 92s or bigger, you need to start with a fresh case that hasn't been abused. You're building a stroker engine that's going to put tremendous stress on this case and you don't need to start with something that's already been abused. I can $how you piece$ of ca$e$ and crank$haft$ to give you an idea what happen$ when thing$ go wrong. It get$ really expen$ive.

What did the former owner use for a head stud? I've seen all-thread and a nut tried, but none of them held.

Are you sure the hole is too big for a case saver? Even if the hole is too big for a heli-coil, there are some larger inserts that can be inserted. A case saver is not a heli-coil and vice versa. What we called a case saver 25 years ago was a steel insert that was threaded into an enlarged head stud hole, and was threaded for the original head stud. A heli coil was little more than a set of threads that were screwed into a stripped hole to restore the original size. Heli coils are a good repair if the hole isn't too big. Case savers could fix a larger hole. If it's too big for a case saver, you need another block.

-- Jack

It's a way of strengthening the block. Stock head studs are set in some pretty thin and soft aluminum. They were pretty easy to pull out. Later model blocks had the holes drilled deeper to get the studs anchored on some stronger stuff.

Ten grand is really good to make pushrods swap rocker arms. Ask me how I know... But rev 10k and drop the clutch and all you'll see is sky. In three gears. My motor was a mistake. I built the frame for a woods buggy and let some friends talk me into the monster motor. The idle didn't smooth out until it got to about 4k and it didn't start making real power until it got over 5k, which is more than a stock motor will rev anyway. I spent all my time either spinning, looking at the sky, or putting in a new clutch.

I'm sure we've already exceeded everybody else's VW curiosity, but I wonder what kind of transmission you're planning to use? Email is OK.

-- Jack

If RDF doesn't give you advice: Try a post to

(US VW aircooled forum) or (UK forum) Is it defiantly an aluminium case not magnesium? I bought some HTS but my case is Mag alloy(AS41) I shall be trying the HTS on an exhaust port crack, so all isn't lost.

Brent, I just put a stud kit on a Keith Black sleeved Hemi for a client. I had six destroyed stud-to-block threads and holes. And some others too. I used the 2000 rod and did not have any problems at all with doing as they demo in the video. I do it just the same. A lot of my client's don't have huge multi-engine deals with me. A lot of us on budgets will buy 2005 blocks, helicoil- (Or HTS2000) them and use them for backup engines and V/E spares. I use it. My dyno does not lie. It can take 1399 hp at 5600rpm on nitrous and alcohol, It's proven itself invaluable. and passed tests a heicoil would fail and a head gasket or the engine would let go. It does look different under Magnaflux but not like a crack, more like a blemish.

Hit me off line if you want to talk,

Rob

Just to fill in a slight gap in this discussion: I have seen Helicoils that are made to repair stripped out Helicoils. I don't know whether they are available in a wide range of sizes, but it IS possible to fix a thread that looks too stripped for a Helicoil.

Leo, You are 100% correct. There are but on some applications where space is really limited by things in an intricate piece of machinery, the engine. And not our comfortable medium of raw stock. With the engines I cant re-open a Helicoil to the next step, In one instance on a KB Kemi that little bit of machining in the helicoil it would weaken the block integrity- the tolerance is that tight before critical failure. In 99% of other reasons the Helicoil is fine but Head studs take a LOT of heat and pressure from just being a part of the engine- that's a lot of multidimensional stresses impacting on it. The Helicoil adds a third element in, thus another point of failure. Repeated use of a Helicoil on cylinder heads or other high /idle cold/heat/stress. They just don't lend themselves too well for this. A more static, non stress part I'll Helicoil in a heartbeat too. Best thing on the planet sometimes. I have drawers of them.

Again, the two cent before tax thought.

Rob

Fraser Competition Engines Chicago, IL.