L88 Stats?
Le Mans Master
Joined: Jan 2005
Posts: 8,226
Likes: 2
From: Lake Wylie SC
There was a change made to the exhaust port when the heads went to open chamber design. I asked about that at Tonawanda (in 1969), and was told that there was an experimental set of heads made with closed chamber and revised exhaust port. That design performed better than the open chamber with revised exhaust port. (I didn't see the data.)
Todays chambers designed for swirl have proceeded way beyond either design of back then but those old rectangular iron L72 heads can be made to make lots of power (although they need less compression)........ you just have to find someone willing to grind on hard steel.
Doug
Safety Car
Joined: Jan 2001
Posts: 4,414
Likes: 763
From: Barrington IL
The 7/16ths rod bolts may have been available in March of 68 but my understanding is that they went into production with the second design motor. The open chamber head was for improved emissions but a side benifit was better flow and more HP even with a slightly lower compression ratio of 12 to 1 vs. 12.5 to 1. Plus other changes to the second design engines were the introduction of the holley double pumper carb with mechanical secondaries and a revised ie. bigger camshaft.
Race Director
Joined: Oct 2005
Posts: 12,470
Likes: 1,548
From: Camp Verde AZ
C1 of Year Finalist (performance mods) 2019
2017 C1 of Year Finalist
Thread Starter
Race Director
Joined: Jul 2007
Posts: 11,467
Likes: 8
From: 972 and 405
Thanks for all the information guys. IMHO this is the best engine to come from Chevrolet so just wanted to get some information on it. The best Corvette engine also. Thanks guys.
-Alex
-Alex
