Closed chamber heads turned into open chambers?

[Steve Antonucci]

Hi everyone,

While surfing the "bay", I came accross this item:

1967 L88 or L89 392 Chevrolet Corvette Aluminum Heads Item number: 4545283145

These are a set of 1967 aluminum big block closed chamber heads that were opened
up to an open chamber-like configuration. I was always told that this was
not possible due to thin wall section in and around the combustion chambers.
Are these one of those "better left alone" type of performance parts?

Still, I'd like to know from you past big block racing types if this is even
a do-able modification, or playing with fire.

Steve

[Mark #28455]

anything can be done with aluminum

If properly done, either they only opened the chamber part of the way (about half way to open chamber size) to miss the water jacket, or they opened it as much as needed and then welded the chamber to produce a new wall. How do you as a buyer know if the part will hold up to usage? You don't. Any time you buy hot rodded parts, you take a gamble. For my money, I would wait to find unmodified parts (they show up on e-bay often enough). If you really want the best performing heads do it right and get a set of the d-port heads (077 castings).

Good luck,
Mark

[Steve Antonucci]

Re: anything can be done with aluminum

Hi Mark,

You're spot on. I agree and I did purchase a set of '077 heads a while ago
based on input from several members on this forum.

These heads in question just caught my eye. Everything I ever read about trying
to open the chambers up on BBC heads indicated that it was risky at best.

I actually didn't consider that the chambers would be opened up, then welded to
form a new wall. Cooling would be my paramount concern with that scenario.

The number of bids threw me for a loop and I just wanted to be sure that these
weren't some trick, rarely seen setup, due to modification costs.

Steve

[Mark #28455]

racing vs street use

Most of these severely modified heads were used in the 70's and 80's for drag racing. I remember Lee Shepherd (of Reher Morrison fame) used the 842 castings rather than the 074 castings but would literally lay down MILES of heli arc bead to totally "re-cast" the entire chamber and ports. This was back when better heads weren't available (for "stock" type racing). Now, there's little reason to use old parts when anyone can get the current technology for less than $2000 a pair.

Mark

[Steve Antonucci]

Re: Closed chamber heads turned into open chambers

Hey everyone,

Those modified aluminum heads are up to $1,500.00 and climbing with 5 days
left. I still don't get the attraction to these heads.

Steve

[Mark #28455]

just another L88 or L89 on the way! *NM*