Hey All, I have a 1966 Delta 88 with a 425 engine. It is still completely stock (60k original miles) with a 2 barrel intake/carburetor and single exhaust.
Did all 425s come with the same heads, hence compression ratio or did they come with different heads/compression ratios? I want to get the most horsepower out of it as I can so of course plan to put dual exhausts on and a 4bbl intake/carb setup.
I have been trying to research this answer as best I can but can't get a straight answer. I read somewhere that there were 425s with 9 to 1 and some with 10.5 to 1 ratios. I also read that all came with 10.5 to 1 ratio combustion chambers.
I figured that if there were experts anywhere on Olds 425 engines, they would be on here. Thanks in advance for your answers.
Did all 425s come with the same heads, hence compression ratio or did they come with different heads/compression ratios? I want to get the most horsepower out of it as I can so of course plan to put dual exhausts on and a 4bbl intake/carb setup.
I have been trying to research this answer as best I can but can't get a straight answer. I read somewhere that there were 425s with 9 to 1 and some with 10.5 to 1 ratios. I also read that all came with 10.5 to 1 ratio combustion chambers.
I figured that if there were experts anywhere on Olds 425 engines, they would be on here. Thanks in advance for your answers.