I have camtech 272 8.6mm cams coming, as well as performance springs.

 

I already have adjustable cam sprockets and silvertop itb.

 

going to be sending a spare head off for a quick port and polish and will have them assemble the head with the cams and springs..

 

I am trying to keep costs down and wondering if i can get away without shim under bucket mod, or if its just not worth the risk.

 

anyone run 8.6mm or more here on standard shims?

I'm no expert but I think 8mm is really the max you want to go, though I've read people push up to 8.5.

Using engineering blue on the std shim turn the installed cam one complete turn and you will see contact/wipe area of the lobe.Odds on it will wipe all the way off the edge of the shim with this amount of lift and will require under bucket Shims.HKS 8.35 mm lift cams wipe just shy of the shim edge.If the cam lobe wipes to the very edge the shim will rock and will spit out the side.

Ahh I see, I actually didn't understand WHY they were needed before. I've done days of research, and read plenty of forums and tech pages, and there's lots of info on how it's done.. But none explain why.

Thanks I guess I will be buying more bits. ;)

Edited January 20, 201412 yr by crunk81us

Anyone know at what lift cam the 4age becomes an interference engine?

Would also depend on if the head has been shaved, the type of headgasket, and exactly what 4age (specifically the pistons) you are talking about.

 

(I dunno the answer though, just prompting more information so others may be able to help)

Smallport 4age standard oem everything,