BlackBirds

iTrader: (24)

I've done some searching and havn't really found anything, but I've got stock heads and a TR224 cam, duration is 224/244, 112LSA, and lift is .563/.563. I'm looking to get a set of 1.85 ratio roller rockers which will put my total lift at .613 at both valves. will this have clearance issues with stock heads and pistons or should I be alright?

SweetS10V8

iTrader: (4)

The heads wont have a problem with .613" lift, thats everyday lift now. As long asa you dont have some wicked spring combination.

You have to check pitson to valve clearance no matter what ANYONE tells you. Because when your pistons and valves crash, its your own fault and you have to pay the bills to fix it.

5.3LJimmy

iTrader: (10)

All of Thunder Racing's cams have the specific instructions: Due to the fast ramp rate of this cam the use of 1.8 rockers is not recommended.

But to answer your question, with the proper spring setup such as PRC or Patriot duals it is possible to run up to .650 lift.

BlackBirds

iTrader: (24)

yeah i saw that too. so would the fast ramp rate mixed with rockers over 1.8 ratio just cause the valves to slam into their seats too hard? The car has PAC 1218 valve springs

5.3LJimmy

iTrader: (10)

I think it would cause valve float or some other valvetrain instability. I really don't think you would see very much gain from just the rocker swap anyway.

BlackBirds

iTrader: (24)

I got ya. the rockers I was looking at getting are also offered in a 1.75 ratio version.

00Formula00

iTrader: (6)

Listen to this.... It is VERY true

BlackBirds

iTrader: (24)

yeah, i know theres no substitute for a clearance test, I was just checking to see if I'd get a "no thats too much" response to just scrap the idea, which it doesnt seem like i'm getting

anyway though, with thunder racing's warning against 1.8 ratio rockers I'm not gonna go with them.

thanks for the info guys