[jerry1]

I have 406 chevy small block taken apart. The pistons are 350ss venolia. on top of pistons have a small raise on top. Side of pistons are dart in color .This engine has pro1 dart heads 200/64/2.02/160. I call Venolia in Calif and they needed a work order number. Anyone know any thing about these pistons. Thank you

 

[nitro_baller4692]

what are you asking?
what is it that you want to know?

 

[327NUT]

Sorry but that part number made no sense to me so I looked up the Venolia web site. Two questions...and please no offence intended, are you sure its a 406, and are you sure they are Venolia pistons. The part number you gave is not listed and why would a 400 chevy have a part number with 350 on it? I would measure the bore.

 

[jerry1]

Yes the motor is a 400 chevy bore 30 over. The pistons number were wrong they are SS350 ON PISTONS. vENOLIA PISTON ARE USED FOR RACING IN MOST CASES BUT LIKE YOU I LOOKED ON THE INTERNET NO LISTING. SO I CALLED THE COMPANY THEY SAID PISTONS BY ORDER ONLY. I ONLY NEED TO KNOW THE COMPRESSION. JUST TRYING. THANKS ANYWAY

 

[camaroman7d]

Figuring out the compression is not an issue, you have the parts in front of you. You know the bore, stroke, you have the heads you plan to use and the pistons. If the pistons are in the block measure the deck height (how far in or out of the bore the piston sits). Measure the valve reliefs and dome, add in the thickness of the head gasket and you will have your true compression ratio. The piston is only part of the compression formula.

 

[johnsongrass1]

The problem he has is those pistons don't have published numbers because they are custom order deal. In ored to measure correctly, he will need buearatte a cylinder.

With a small dome, and leaving it at that I'd say 12:1 maybe?