Do you think 680/270 to big for 10.1 comp on a street motor
No.
No.....But its no subtle either....What's beautiful about a Hemi, is its resistance to detonation....I would turn the compression up to 12:1 or 13:1 if I was building it as a pro-street or a little raced street car. If you keep the timing in check, you will never have an issue.
Better off getting 12.1 comp pistons then ?
Or stick with 10.5 comp pistons
Thank you for your help every body
Sorry but the hemi chamber isn't really that great, it's just "ok". I think you are fooling yourself if you think it's not gonna rattle with 12:1 on pump gas, especially while driving it. No matter where the timing is. The pump gas is freaking awful, even worse than it was 5 years ago. And 10:1 is pretty darn low for a long 270 duration. I talked to Tim Goolsby from Bullet/Ultradyne last week about a 272 in a 10.5 to 1 setup and he thought it was pretty long also. It's gonna soften it up.
