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8.0-8.5:1 compression with vic jr heads?

Intake, exhaust, and cam would be changed as well but just wondering how bad it would run.
 

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brains
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With aluminum heads you can get away with 9.0 - 9.5 compression and still use pump gas. If you dont plan on building your lower end, and just doing heads, find a set of heads that have smaller cc'd chambers.


Ben
 

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You can get away with up to about 11:1 with aluminum heads on pump gas "IF" you set things up correctly.

To answer your question with compression that low and heads that big you will have a very mushy bottom end. No torque at all and very little power until higher RPMs but it is not going to want to rev to the higher RPMs unless you have a healthy cam, which in turn will need more compression. As you can see it is an endless loop. The heads are not a good match for a low compression, small cubic inch engine.

Royce
 

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I agree with camaroman. I would look into the AFR 165's with a mild motor like that.

Adam
 

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Discussion Starter #5
brainsboy said:
With aluminum heads you can get away with 9.0 - 9.5 compression and still use pump gas. If you dont plan on building your lower end, and just doing heads, find a set of heads that have smaller cc'd chambers.


Ben
The plan would be a 393 as we had talked about, and i figued smaller cc intake ports such as the rpms might be flow limited for a bigger inch motor. Figured i could swap heads now and run them and a bigger cam for a while until i have enough money to get all the bottom end parts i want.

guess i'll just run with what i got until i can do everything at once :(
 
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