L134 Piston question

[AeroE]

Are the pistons for the L 134 engine and M38A1 F head the same? Federal lists them as such, but MAHLE lists pistons only for the F head. I prefer MAHLE.

[wesk]

I see that happen often. Many manufacturers will list them as F-134 when their product fits both. Look at the 09 Mahle catalog http://www.mahleclevite.com/publications/PI-20-09.pdf and go to jeep then down to the Block 1 entry:

[AeroE]

Thanks-I did confirm with MAHLE that they are the same. On the bottom of the catalog page, as you cited, they show “Flat head, L and F”.

I went with 5007 cast iron rings figuring I’d rather wear the rings than the block, and I don’t put that many mile on it.

[GPA]

There is a difference in crown thickness and weight. F-head is thicker and heavier. But judging from experience in high performance engine building, even the thinner L-head piston is sufficient for F-head use. Wes?