Okay, I think I found a good deal here, so I ordered them up!
Good news for your guys is that this is state side, so you won't have to pay the $60 sipping I did. However, all told I'm $356,00 into a NEW set of 94mm Mahle pistons and cylinders.
Mahle Engine Piston Set
94Mm
Cr 8:1
Euro Spec
Includes Cylinders
Std. 94Mm
Porsche 914
1973
I found them on
Car Parts DiscountSo if you guys are trying to build a good stock 2,0 engine on a budget, you might look over here. I'll let you know what shows up. I've heard some chatter about the Mahle main bearing quality out of Brazil (this and other threads) but I've yet to hear anything negative about the pistons, rings and cylinders from any source.
This is actually the same price for me as a set of 96mm AA pistons, but I really worry about those AAs. As much as I like working on cars (and I do love it ;-) I don't want to pull this motor out and tear it down over and over again.
When I was doing my little Austin Healey A-series engine, I had it out 3 times trying to solve an oil leaking problem. They have a very interesting rear scroll type seal that means there is no physical silicone seal. This equals nightmare! If you have even the slightest amount of positive crankcase pressure, it will start blowing oil out of the rear "seal". I discovered this when I had the engine block over bored 0,030" and used some cheep oversized piston rings. The spec gap for the rings installed was <0,007". With new rings I had ~0,020" Then I started this in out business with the engine. I had to tear it down multiple times thinking that this piston ring gap couldn't be the problem. After all I had 3 compression rings, oil control ring and a skirt ring on each piston, all rotated 180 out from each other, good compression, and good leak down results. What you can't measure with all of that is, what is the leak down when the engine is slightly above operating temp, and running at 4500 RPM. Well, that is when the oil started coming out. I discovered this by connecting a senstive pressure gage to the dipstick tube, then running the gage up to the dash (not so far on a Sprite ;-). I would drive around at different RPMs watching the gage, and jumping out to look at the bottom of the car always clean. It didn't go into positive until I got to 4500. Then I jumped out and saw oil dripping out of the bell housing. It also wouldn't build up any positive crank case pressure without a load on the engine. Eventually I changed the rings out for some "file to fit" rings, got all the gaps just right and not a drop of oil at any load or RPM!
So I'm a bit nervous about these AA pistons, I'd rather not take a chance with an aluminum engine.