Alright I am going to build a 393 stroker out of a 351W. It will uses the stroker crank, stock 351w rods, and 302 pistons.

My question is becuase of the longer stroke will the 302 piston be higher compression than advertised for a certain head volume or will it stay the same.

I would like to stay around 10-10.5:1 with the stroker.

 

Brian, It will be higher. But I think you can find good, cheap heads that will meet your compression goals. Do you have an engine already? Do you have heads?

 

www.kb-silvolite.com has a good selection of both 302 and 393 pistons that should give you the compression you are looking for. They also have a nice compression ratio calculator.

 

Brian - There are a few variables when getting that 393 at the compression you want without ending up with a racing motor only.Do the www.kb-silvolite.com calculator and study it well with all the part choices out there for your combination. My parts ending giving my stroker 10.8:1 -

Scat crank 3.85
Eagle h-beam rods 5.956
Weisco pro-tru flat tops -5cc volume
World Victor Sr Aluminum heads - 64cc
Fel-pro head gaskets - 4.100 bore / .039 thick

I purchased my pistons before doing my calculations because I got a great deal on them so I had to settle with the 64cc heads;wanted to run Trickflow or Edelbrock but their cc's would have put my comp. ratio way over the top for a street driver with 93 octane.

 

[updated:LAST EDITED ON 05-Jan-03 AT 09:31 PM (EST)]I will be using a 3.85" crank with stock 351W rods and Edelbrock, or Trick Flow heads with 58cc chambers. I would like to end up with around 10.5:1 compression.

Does your motor do alright with pump gas with the 10.8:1 pistons. I have heard you can go a little higher with the compression if you have aluminum heads.

EDIT:
My engine block is an E4AE casting. I would like to install a roller cam in it what will that involve doing that since it is a pre-roller cam block.

 

Check out http://www.trickflow.com/articles/stroker_2/at_st_body.htm - they did a 393 buildup listing all the parts used and with a Crane retrofit roller kit in a 79 non-roller block. You will have to run a retrofit cam to make the swap work in your 84 block and continue to run your numbers through http://www.kb-silvolite.com/calc.phtml.

The 58cc heads you are looking at may push compression on up unless you can find a piston to offset this; my stroker runs like a scalded dog on 93 pump gas.

 

Could you re-post the link to the trick-flow article the link above does not work.

Thank you

 

If you just go to trick flow and look up articles you will find it I just went and read it