View Single Post
Old 11-08-2014, 02:01 PM   #7
greg64
Registered User
 
greg64's Avatar
 
Join Date: Dec 2007
Location: Kimberley, BC, Canada
Posts: 799
Re: Compression ratio question

Caleb, I'd say the answer depends on a lot of factors.
First, how hard are you going to work the engine? If you're just going to cruise around town, the higher CR will probably be fine with the aluminum heads. But, if you're going to tow, and really work the engine up big hills (I live in the mountains) then I'd go with the lower CR.
Second, the cam has a lot of effect. The more radical the cam, the more CR you can get away with (obviously within reason). If the cam is stock/mild, I'd lean towards the lower CR.
Third, how close to the top of the deck are the pistons? The further down in the hole they are, the lesser the squish, which reduces the turbulence, which reduces the mixing, which makes it more likely detonation will occur.
__________________
Greg
64 GMC Suburban - 283, NV3500, 14 bolt
77 C10 swb - 292, SM465, 12 bolt
greg64 is offline   Reply With Quote