[Henry Schmidt]

Here's a long needed update.

One of our customers elected (with my blessing) to buy a set of Mahle 100's for a 3.5 engine we're building. The cylinders arrived new in the box with mismatched pistons and cylinders. Cylinders were 0 and pistons were 2.

Mahle offered to replace the cylinders as soon as they could verify the origin.

In an attempt to make the process move more quickly, we sourced a set of 2s at Andial. They offered to trade. Those guys ( Pete and Dieter) are great for helping, remember there was nothing in it for them.

When the cylinders arrived we checked them for ovality (just a habit now) and found that they were .0005" to .0008" out of round. If they were QSC we would have rejected them. Don't misread this as a criticism of Andial, it is not. I repeat they were great to help.

I called Mahle Motorsport to ask them about the inconsistency and they thought it was a little high but they should work just fine. What?
He told me that Mahle does not use a bore gauge to measure their cylinders. They use differential air pressure. I sure wish we could afford equipment like that.

While talking to the tech, he told me I could just tap on the cylinder to make it round. "one good rap should do".

I wonder if I told my customer that I beat his cylinders into spec if he'd let me finish his engine?
Who know? My guess is that ovality in those small increments is not an issue.

QSC cylinders are going out of Supertec with less than .0002 ovality.