which would be the best for a 12 to 1 compression 355 reving to 6800-7k.

I am between the crane 99893s dual spring
1.460" outside diameter
130 pounds seat pressure
402 pounds open pressure @ 1.150"
Set of 16

or the pac 1218s beehives
seat 130 @ 1.800/ Open 318 @ 1.200

 

Depends on cam lobe. What cam?

Dan

 

Beehives, hands down. Do a search using my name and the term beehives if you need a good education on them.

Bret

 

Will do, I am pretty much settled on the pac 1218s or 1518s, possibley the 1220s and have my heads machined to fit.

 

You have to do more than open the spring pockets for the 1220's, you need longer valves as well. The 1218's will work just fine.

Bret