I have wanted to get up to speed on the subject of Gen 5 top swap-ability. So in my reading, the subject of short block health or getting a durable replacement/short block naturally came up. In 8 threads L26 was identified/mentioned as a durable alternative to the L67, for a concurrent Gen 5 (MOD) on 2 occasions. This gave me the idea for a new thread to help me understand why L26 has risen to the occasion, to sit under forced air induction, in the good company of L67 (GTP/Eaton M90 Gen 3), L32 (GTP/Eaton M90 Gen 5) and last (but definitely NOT LEAST) LC2 (GNX/Garret GT35R).
This thread’s purpose is not to question the wisdom of using the L26 as a foundation for the Generation 5 M90 Supercharger, but to understand “what is going on with the L26 that allows its non-hardened piston's to "rise the occasion"?
I thought "Forged" & "lower compression ratio” (i.e. 8.5:1) aspects of pistons go together (hand-in-hand) and that these 2 things were inseparable, at least in the context of “3.8/231 & 3800 V6” & GNX, forced induction systems, like L67 & L32.
Isn't the L26 (I know the arms are substantially improved) using pistons that are still lacking in the “forged /hardened & lower compression ratio” department, at 9.4:1? EVEN WITH "the stronger powdered metal sinter forged connecting rods"? I guess I would have thought that this made the L26 substantially limited in its application to our "forced air induction" applications, here due in part to the "weakest link" theory. This thread’s purpose is not to question the wisdom of using the L26 as a foundation for the Generation 5 M90 Supercharger, but to understand “what is going on with the L26 that allows its non-hardened piston's to "rise the occasion"? Don’t mean to “pick nits” but is there a substantial difference in GTP piston application and GNX piston application?
I guess the “nagging” question that really wears at me is this:
“Is there a substantial difference in “piston hardness (i.e. short-block durability)” one way or the other, between the 1987 GNX (GM Production Turbo w/LC2) and my 2000 GTP (GM Production Supercharged w/L67)?
All thoughts and comments are welcomed, positive (and negative).