f-303 and stamped rockers
 

Hi everyone-

Here's what I'm planning and why, looking for some feedback...

306 with f-303 cam, Cobra upper and lower intake, with stock springs/stamped rockers.

I'm not going to run rollers because I'm not extending or eliminating the rev limiter. So, I don't need the rollers to float.

Is anyone running anything remotely close?

Thanx in advance...

IMO that won't work too well. There will be some people that'll say it'll be fine if you don't over-rev (ie Valve Float). But the springs won't be enough from a stock head, there's not enough seat pressure in them, so I recommend new springs at the very least.

The rockers would be alright for now. Rollers would be an improvement of course, but if you don't have the cash, then you can use them.

Hey 86GT-

Thanks for the reply. Here's my concern- I've heard some stories about having to replace roller rockers too often, and that they're more trouble than they're worth.

I've already got the roller rockers, came with the rest of the Cobra setup, from a '94 Cobra, and they've already got a lot of miles on them.

If I keep the stamped rockers on, I think they'll last a lot longer, and be more reliable. What would you recommend for springs to go with ported E7's and an f-303 cam with the Cobra setup?

Thanx again

no rollers?
 

To me, not to be disrespectful, but adding a high lift cam and running old stock valve springs is a big mistake, you will never utilize the cam's potencial, and as far as Roller Rockers having to changed all the time is bull, I would much rather have rollers with 100,000 miles on em, than a brand new set of stamped, they will flex, etc.........it has nothing to do with extending the rev-limiter, with stock springs you may not even MAKE it to the rev-limiter.

Jay

Rollers are the best thing for a big cam. The reason is that they don't flex like the stamped ones. The wear thing is common, but not a huge problem. I've got my Crane Engergizer's with approx. 80,000kms on them. They've made a ticking sound from day one. Just check for visible wear on the roller tip, and too much side to side play. Other than that, I'd suggest using the rollers over the stamped.

As for valve springs, if you're running the stock heads, TFS makes an upgrade kit, available through Summit, and its got everything you need in it, shims, springs, locks, retainers, seals, etc. Call them and tell them what you're doing, and they can help. Otherwise Ford Racing makes a set that'll work too, but I'm not sure on the part number.

roller rockers
 

I don't know where you heard those stories but they are way off. As gtsr515 stated...no matter how many miles are on the rollers DEFINITELY use those over the stock stamped ones. When running the stock stamped rockers...there is metal rubbing (or should I say grinding) on metal with just some oil in between the two. It's just common sense to think that a roller, ball bearing tip on one end of that rotating part of your motor would work much more efficient & smoother. Use the rollers.

The "F" cam is too much cam for your combo. F cam and stock heads is a bad idea. You would go faster with the B-303 cam.

The only person I have seen run a F cam with stock heads ran slower than with the stock cam.

I'm running an F-303 in the 89 with ported stock heads. True, they are a bottleneck and a set of TFS heads are coming soon. Slower than stock. . . . not hardly. We'll know for sure tomorrow.
Look at the roller rocker thing this way. Stock springs aren't going to work very long with the F303. It needs stronger springs. I did run the engine for a few weeks with the stock rockers and no valves ever floated up to 6200 rpm. BUT!!! With the heavy valve springs required for this cam, there was too much spring pressure for the stock rockers and they were beginning to wear into the fulcrums. Too much pressure forces out the oil and galls everything. Now. . . .I can't say I noticed any big power increases after the roller rockers but it does rev really easily. First gear will often bounce off the rev limiter often quicker than I can get out of the throttle. (MSD 6AL set at 6000 rpm) but that's more of a traction problem than anything else. I would go with the roller rockers if the F303 was in the future.

Thanks for the input, guys. I'm still looking at the following combo's:

1.) 306, ported E7's- Cobra upper & lower, roller rockers, f-303 cam, mass air conversion

2.) 306, ported E7's- Cobra upper & lower, roller rockers, stock '88 speed density cam, speed density setup

3.) 306, ported E7's- Cobra upper & lower, roller rockers,
e-303 cam, speed density setup

I'm leaning toward #2, just to see what I can do with it. Number 3 is in 2nd place, and #1 in a distant 3rd...

Thanx...

JM