Mercury Cougar Owners banner

1 - 3 of 3 Posts

·
Registered
Joined
·
5,299 Posts
Discussion Starter #1
ive been getting the itch for a lil more power for my car... and ive looked into a set of roller rockers for it. i know its not an optimal choice given the modifications that the car currently has, but i have an impulse buy feeling right now and i want something lol. question is.... if i get the 1.7 ratio roller tip rockers, will i have any piston valve interference?? ive been told a full roller wont fit under the valve covers i have now and a roller tip rocker arm seems to be the only way i can go for now. im fine with that but i dont really want to keep the 1.6 ratio. i figure i might as well go for the extra lift. i just dont want any kaboom. the engine is a 69 351W with pedestal mount rockers. originally a 2bbl car so i know th pistons are dished.... so will they clear?? if so i shall order them :) they arent in stock at the local speed shop at the moment...
 

·
Registered
Joined
·
5,299 Posts
Discussion Starter #2
nothing ?? no clues or ideas?? hmm, im sure someone has done or at least thought of it before..... either case im basically just typing here to bump the thread up again.. he he
 

·
Moderator
Joined
·
11,000 Posts
Rocker ratio roulette

You are taking a chance any time you modify the valve to piston relationship without checking clearance. If you have forged pistons and a valve kisses a piston it will just bend the valve and make the engine run bad.

If you have cast pistons or hyperutectic (long word that means cast pistons) then when the valve touches the piston the piston explodes like a little grenade. The connecting rod is now free to choose its own course in life which means it will go right through the side of the block.

You won't know for sure until you try. I recommend a thorough check of valve to piston clearance.

Royce Peterson
 
1 - 3 of 3 Posts
Top