Keeping it original
Thread Starter
Drifting
Joined: Mar 2009
Posts: 1,461
Likes: 361
From: Monson MA
Keeping it original
I did post this in another section. But please give your thoughts.
During my restoration I will get to the engine rebuild. I would like to keep things as close to factory as possible. The L79 had 11:1 CR. I am wondering based on all I have read, can I keep this 11:1 CR and run on 93 oct.? It is still not clear by the articles and comments I have read. Some say yes and some say no. I am confused. This same frame of mind seems to be the same with a couple of engine builder I have talked with. I have been told to install Aluminum heads and I should be able to keep the 11:1 CR. Please give me your input.
During my restoration I will get to the engine rebuild. I would like to keep things as close to factory as possible. The L79 had 11:1 CR. I am wondering based on all I have read, can I keep this 11:1 CR and run on 93 oct.? It is still not clear by the articles and comments I have read. Some say yes and some say no. I am confused. This same frame of mind seems to be the same with a couple of engine builder I have talked with. I have been told to install Aluminum heads and I should be able to keep the 11:1 CR. Please give me your input.
Race Director
Joined: Jan 2000
Posts: 13,013
Likes: 2,253
From: Corsicana, Tx
2020 C2 of the Year - Modified Winner
2020 Corvette of the Year (performance mods)
C2 of Year Winner (performance mods) 2019
2017 C2 of Year Finalist
Lots of variables here. First..yes you can run a true 11.0+ compression on 93 octane as long as rest of combo goes along with it. Your 327 was rated at 11.0 but in all reality was closer to 10.5 at best most likely.
The cam is the big deciding factor really. It's all about controlling cylinder pressure in the RPM range you will run it. Are you married to the original cam?
The real advantage of the aluminum heads will be as much about chamber design as material. Better chambers allow more compression.
Can the cooling system keep it under 180*?
Tuning distributor timing curve will also be critical...but yes it can be done. Just dpends on what you really want to do with it.
JIM
The cam is the big deciding factor really. It's all about controlling cylinder pressure in the RPM range you will run it. Are you married to the original cam?
The real advantage of the aluminum heads will be as much about chamber design as material. Better chambers allow more compression.
Can the cooling system keep it under 180*?
Tuning distributor timing curve will also be critical...but yes it can be done. Just dpends on what you really want to do with it.
JIM
