ShopTalk Forums | Aircooled VW Tech & Restoration Help

Proextreme, I think I see light at the end of the tunnel,,please bear with me one more time,, so there's obvious stress on the areas Jake pointed out to us, this is also known because those stress-points are also points of constant contact,,, duh me. There again since cryo helps relieve stress, would it help, or would it be a waste of time and money on those particular parts, and would it be detrimental to the micropolishing process ? Or am I barking up the wrong tree altogether?

Micro-polishing is alittle different than polishing for looks. In micro-polishing we are trying to remove the peaks and bring them in closer to the valleys. With that said the harder a material the easier it is to obtain the surface finish you are looking for because you have more resistance with harder materials. Because of this you would use diamond as the abrasive to polish. Diamond hands down is the best abrasive to polish with, but is so hard and free cutting that polishing a soft material with diamond most of the time does not give as good of results as with hard material. Cryo will not effect the polishing of you lifters. We have tried cryo on the valve train and we feel at this time we did not see the benefits for the cost.
Proextreme

Thanks Proextreme, I appreciate your candor and patience in answering my questions.

I have tried cryo on ALL components of the Type IV at some point in the last 5 years. I have seen positive results from it, but have not directly tested it in the same engine with non cryoed parts.

We are doing that now, in a 2332 R&D engine....

BTW, we cryo parts in large batches and the cost is not that bad in bulk. My cryo guys work very closely with us and have developed some profiles just for the Type IV that kick butt!

Nicely put about the hard surfaces and polishing. As an example, I have a gauge I use every day. It is a magnetic induction gauge that measures film thicknessto the 1/10th micron. It has a probe...and a metal target to put on the other side of the film. I have lapped the surface of it...with 2 micron diamond paste. Smooth as a metal babys ass. But....its mild steel. Every two weeks, I have to lap it again...because contact with any material...even paper...wears at it. Under the microscope....soft metals produce rounded peaks and valleys...and polish easier...but because they are so soft....they get un wanted "extra" peaks and valleys...because they are so soft...that ANY rpeated material contact ...gouges them in an irregular fashion. Thats another thing. Polishing technique is also important. The abrasive polishing material must be applied and used in a very regular and predictable fashion...to produce a uniform surface grain. That grain size as noted...is expressed by Ra. The unifromity or pattern of it...is expressed by the Rz. RAY

Just a note. The people in the VW world have a gold mine of knowledge in Jake Raby and Air Cooled Technology. We have only been working together on the VW valve train problems for a few months but I can say he and his company are ready to try what ever it takes to solve
problems.

Thank you
Performance Research inc
ProXtreme Valve train

Pro-extreme, that was one hell of a compliment coming from you!

The lifter testing is done, finished it today. The cam and test lifters are coming to you tomorrow!

Lets get to the bottom of this!