valve lift with 1.7's and tfs cam?
 

Tfs #1 cam, .499/510 intk/ex

Now what will lift be with 1.7's? is it out of the question with stock pistons and gt-40 heads? or is it worth at least checking with clay? im real close to ordering one?
thanx for any help...

btw, started pulling belt, radiator, upper intake today, slowly but surely getting ready for these heads.

Ive got a set of Gt-40 heads im gonna put on my 306 with 86 style pistons. ( not valve relieved liek the 87+) I am wanting to rubn the trick flow stage 1 cam as well. If you run this and check the clearances with Clay please let me know what kinda measurements you get. It will be a long time before I get mine together ...

Thanks
Bradley

Well clay wont tell me the actual clearance, but im afraid of 1.7's putting the exhaust lift past .530, and thats asking for trouble on stock pistons,

if you have 86 pistons coupe devil, they will not work without notching, you could probaly buy new pistons and save the hassle.

I think the TFS cam is calculated at 1.6's for those lift numbers. You'll have to check the "@.050" lift on the cam card and then mulitply that by 1.7 to get the new lift. My buddy is running a TFS1 cam with TFS heads @ 1.6 with np. Very snappy cam too I might add! motor wraps up quick! Not sure about the GT-40's though. But it is always a good idea to clay...just to be sure.

Lift
 

1.7 rockers are .30 more than 1.6's........there you go......

Jay

ok, so i guess my question is, what is the max allowed on stock pistons, can i get away with .540?

ive seen it done, but i have also seen the same person smack a few of the valves.
just clay it and go from there

With the 1.7's the lift will be .530 intake/.542 exhaust. A clay test will tell the exact clearance.

Murdock

I talked to a guy that said he's done this combo with e7's, he said he has also heard of people banging valves, i might just have to buy new rockers.