Roller Rockers????????

EarlsflyinCobra · #1 (**permalink**) 08-23-2003, 09:15 PM

I am building an 89 302/5.0 block using forged pistons and rods and the Ford cam E303. I was wondering which roller rockers I should run with this set up?? Aluminum or Steel, 1.6 or 1.7?? Any thoughts/experiences would be appreciated. I am also wondering if I should use the stock heads with better springs and rockers, spend about $600.00 to have my heads worked on, or get a set of the GT40 heads?? I will be running a Garrett T4 turbo also.

Thanks, Earl

HighPlainsDrifter · #2 (**permalink**) 08-23-2003, 10:27 PM

Hi,
I ran an '87 LX coupe with a TO4B 15 years ago now.
The worst thing is the wimpy 7/16" head bolts, you'll blow head gaskets. While you have the engine at the machine shop to get bored, get them to drill and tap the head bolt holes for 1/2" 351 head bolts. You can torque the heads down to 95 lbs instead of the 70 for a 302. Small port heads are fine for a turbo as it will blow air right through any restriction.
Perry.

CowtownCobra · #3 (**permalink**) 08-24-2003, 06:23 AM

Use the steel roller rockers. The aluminum are one season and then throw away. I have been very satisfied with Comp Cams.

EarlsflyinCobra · #4 (**permalink**) 08-24-2003, 09:16 AM

Okay, any other comments on steel vs alum., and also....1.6 or 1.7????? thanks, Earl

EarlsflyinCobra · #5 (**permalink**) 08-25-2003, 11:34 AM

Nobody wants to tell me the differences between using 1.6 and 1.7 rollers will be?? I am using the Ford E303 cam. Any other comments on steel vs. aluminum??

Mr.Fixit · #6 (**permalink**) 08-25-2003, 12:05 PM

The difference will be 6.25% more lift with the 1.7's. Make sure the valves won't be touching your pistons before increasing lift. Use the steerr roller rockers, the aluminum ones are a throw away item after a certain amount of use. the steel ones are just as "light at the valve"

DAVID GAGNARD · #7 (**permalink**) 08-25-2003, 12:29 PM

Earl;

Rocker arm ratio,be it 1.5/1.6/1.7,multiply the actual cam lift by that amount.....Just depends on how much total llift you are looking for....

As far as alum. vs. steel goes,I've heard all the stories... Alum. is lighter and better,but wear out,now they make steel ones just as light,but do not wear as bad....etc,etc....

When I built my engine in 1996,I bought the Crane Cams alum roller rocker arms in 1.6 ratio,they have been on my 351-W with approx. 350hp since then and have a little over 20,000 miles on them and have seen about a hundred passes on the drag strip shifting at 5500 to 6000 rpms and about 200 miles of open track now,I set them when I put them on the engine and have never touched them since,I also used some good poly-locks. Take that for what it's worth....

BTW,if the price is competitive and the weight about the same I would probably use the steel ones in the future...

David

Jack21 · #8 (**permalink**) 08-31-2003, 05:11 PM

When I built my engine, the machinist strongly recommended steel rockers for the street. Using CompCams pro-magnum steel. They're trouble free, and last forever. Price about the same as aluminum ($250).

Actually, Comp advises returning steel rockers to factory when engine is apart for valve grind or rebuild. They replace the trunions and roller tips for a nominal fee and then they do literally last forever.

Used standard 1.6 ratio. Hydraulic roller cam gives all the lift the engine needs. For a wimpy cam with not enough lift to start with, the 1.7's make sense. Do, however, use the larger rocker stud.

Heads. Take a long look at Rouch iron heads, TFS Street TW, AR 165, or even Edelbrock aluminum heads. Nix the stock heads for a variety of reasons, and you can do a lot better than the GT-40's for the same money.

Also like the idea of drilling & tapping the block for 1/2" 351W head bolts. Blown head gaskets are rarely a problem with 351W's, and a constant problem with 302's. Also, use ARP bolts on heads, and rods, and studs on the mains.