rocker arm ratio

[INNES]

i just picked up from the boneyard GT-40 heads off a 97'explorer (not GTP). It looks like the rocker arms on it are 1.5 cause i see the #5 on them.I plan on replaceing them anyway. the question i have is can i put 1.7 on it. i know the 93/94 cobra had these heads w/1.7 rockers.Are the heads completely simaler or are they alittle different and i have to machine them a little

P.S my car is a 88'thunderbird w/a mass air 5.0 motor auto

[351wStang]

The heads will be fine with 1.7 rockers. Its the pistons and valves I'd worry about. Gotta makes sure you have the proper piston to valve clearance.

[HiFlow5 0]

With 1.7 rockers you should be fine, you not increasing the valve lift a ton by going with those. If you have a performance can and added 1.7's then I'd be sure to clay the pistons.

[351wStang]

What sre the stats on a stock 5.0 HO cam?

[HiFlow5 0]

Originally Posted by 351wStang

What sre the stats on a stock 5.0 HO cam?

Cam or rockers? The cam really depends on the year, since there were lots of minor profile changes thoughout the years. But it's valve lift is right around .416/.444, intake/exhaust. Stock rockers were designed to be a 1.6 ratio.

[SVTcobra306]

Checking is never a bad thing, but you should be fine. Be sure and put a good set of springs on, the Explorer springs usually weren't very strong (mine had uneven pressures at 104K, a buddy's had the same at less miles....