found this

thought it might help

The easiest way to use a roller cam in the 351w is to find a F4TE casting number block from 1994 and later F-series trucks and E-series vans.

 

Ditto on the factory roller. If it's got one, it's the same F4TE roller that's used in the 94-97 F & E series trucks and vans, also used in the Explorer/Mountianeer. I'm pretty sure my 95 E150 van had the roller, in 150,000 + miles the performance never changed. Just sold it yesterday so there's now no chance of pulling a pushrod to check. I don't agree about the intake being a bottleneck though, but the heads surely are (on the exhaust side) The Intakes runners are huge compared to any of the Stang intakes, a throttle body change would improve the flow more'n likely.

 

Two things wrong here: Crane doesn't make an XE-254H, neither does Comp Cams, who makes the XE series cams and they don't list it, they do list an XE-256H. All in all, the reason the Stang GT roller made more power was due to it's longer duration over the XE-256H, the lift specs are a tad higher with the XE, unless you use 1.7 rockers on the GT cam. The GT's duration is 276/276 @.005. The XE256H is more compareable to the Ford F4TE roller in duration, and lift too if you use 1.7 rockers on the F4TE.

 

The GT roller cam is 266/266 advertized duration and .444/.444 lift (with 1.6 rockers). The duration at .050 I've seen listed as being 204/204, 212/212, and as high as 214/214. The LSA is 114*. There were some minor revisions over the years. In 89 (IIRC, or it may have been 91) they reduced the ramp slopes slightly to reduce lifter noise. There were a couple of revisions on ramp slope between 85 and 93. This could have changed the duration at .050 without changing anything else. There are subtle differences in Mustang HO cams, but they are good. Ford hit a home run with that cam.

Anyway, I believe the Mustang HO roller cam is a much better cam than the F4TE truck roller cam, even for a truck or an Explorer. It will produce a lot more HP everything else being equal, and still have plenty of tourqe, maybe more. Always run a HO cam with 1.7 rockers if you can. There's a noticable improvement in tourqe with a 470/470 lift over 444.

Speaking of Mustang roller cams, the 93-95 Cobra roller cams are similar to the HO, but they are not actually the same, so one must be careful. Ofton these cams are thought to be HO cams and they came in the Motorsport crate short blocks from 93. All Cobra cams made .484/.484 lift using 1.7 rockers. The 93 Cobra cam was rather soft on low end tourqe, and the 94-95 was an over compensated revision. A 93 Cobra cam will not work good in a heavy vehicle. The 94-95 Cobra had lot's more tourqe, but was lazy above 4500. All Cobras should go to an aftermarket cam, and that really wakes up that motor big time. The E303 is great in that motor, in a manual tranny application.

 

If the 266/266 figures are true, the place the F4TE shines over the GT is with an engine with less compression. Otherwise the specs are so close, it's not funny. The F4 cam just has 10 degrees less on the intake side and slightly less lift. Run it with 1.7 rockers and it equals the lift of the GT cam. The F4TE gives the dynamic ratio a lift there. I'm running one in my V8 Ranger with a 4 speed and 1.7 rockers and it's a blast to drive. This Ranger weighs in at 3800 lbs with the driver.

 

As far as I know, the 96 and early 97 F-250's (just before the HD truck body style change) got roller cams. Roller 351 blocks started showing up as early as 93.

The number on the Crane cam I posted was a copy/paste from the owner; it may have been a typo on his part.

My point was, for the money, a stock Mustang HO cam/roller conversion is very inexpensive. The HO cams, lifters and hardware can be had for less than most aftermarket roller cams alone; I paid 40 bucks for the roller lifters, dogbones and spider, used.

 

There may be a big difference in the ramp rates, and hence duration at .050, between the HO and F4 cams.

I look at the performance of some of the F4 equiped motors and can't help but think, that they should do better than they do, and they might well do better with the HO cam instead. The Explorer 5.0 motor is a good example. Here we have a GT40 motor getting basically the same HP and tourqe as an HO.

Both cams are probably good enough for tourqe application, but going with a HO may be a bit better, especially if it costs less.

 

being roller setu is nice but for a motor that my never see rpms higher then 5000rpms would you think its worth the hassle? i have a f4te motor and boy does it rev smooth but rarly have i had the rpms that hi. a flat tappet would be fine in this case wouldnt you agree?

 

I agree.

A flat tappet cam is fine for many if not most applications, and a big flat tappet cam is usually less likely to float the valves at high RPM, than a big roller.

The principle advantage of a roller in a street application, is that you can get more duration at .050, without much increasing overall duration and overlap. For example, a flat tappet cam with a duration at .050, of say 216*, may have perhaps 60* of overlap and perhaps 272* duration overall, with say .500 lift (these are just hypothetical numbers). A roller may give 216* at .050, with perhaps only 50* of overlap and only 262* duration. The roller will give about the same performance and revability, but idle and run more smoothly, and probably get slightly better gas milege.

Rollers are naturally a little noiser though. Run a big aftermarket hydrolic roller, with roller rockers, and it might sound like a solid lifter setup! People don't like hearing slight ticks and and a little lifter clatter on factory stock engines. They want engines to pur. Sometimes, efforts to reduce the slightly greater noise of a roller cam results in a less powerful cam than it could be.

 

Yeah, mine never really sees the RPMs above 4500, and thats only when im destroying my spider gears by spinning cookies and doing burnouts. I've heard that if it is a roller cam, just putting on 1.7 rockers will help it get to the output of the Mustang HO cam. And no, I don't think its worth the trouble for all of that if I'm not seeing those high revs anyway. What I was wondering is that if I had a flat tappet, I would probably upgrade to the Comp cam that is able to mesh with the computer, but if I had a roller cam, would it be better to just leave it in there and/or put in the Mustang one and 1.7 rockers?

 

The Mustang HO cam isn't really a high rpm cam. It's peak tourqe is only about 3200 and the peak HP is like 4800 to 5. If you have or can get a F4 or a HO roller cam, then that's good, especially with some 1.7's. In the case of a stock flat tappet, I'd be tempted to upgrade to either of the factory rollers, or to an aftermarket flat tappet cam. I'd probably prefer the HO myself. Whatever is most expediant and cost effective.

 

and theres no way to tell which kind of cam i have until i pull of the intake manifold? i know about the casting number to see if its a roller block, but theres nothing anywhere where I can find that out without pulling parts?

 

for low rpm I would go with a rollor if I had the block for it.

 

that is correct, will more then likely need to pull the intake.

 

If you have a 351 roller, then it's gonna have an F4TE, if it's a 5.0 in a pickup or van, the pre 94 motors got the "base" roller, same small one the Crown Vic's and such got from 87-on. If it's a 94-up 5.0 in a pickup/van, it'll have an F4TE. And an upgrade to the 1.7 rockers, should be done if for no other reason than the friction reduction, as for high rpms, the pedestal rockers aren't much good for that anyway. Ford says just swapping to the Cobra rockers results in a 15hp gain. This is both from the friction reduction and the increased lift. My 5.0 in my Ranger pulls hard to 6000 when the lifters start bouncing, with better lifters, I'm sure it'd pull to at least 6500.