I would have gone into detail why the cobra cam sucks, but if some guy in a magazine said its good I'm sure it is.

Have you ever looked at most of these morons in magazines. DOESNT MEAN THEY KNOW ****.

Im not by anymeans being rude, but I do know wtf Im talking about.

Your beginning to build a mismatched combo that isnt going to run right. You need to build lowend on a lightly geared AOD. IF your going to use a cam, go with a E-303 and advance it it 2 degrees to help build lowend. But using the HO w/ 1.72's is way better than a POS cobra. Ever seen how those run in stock trim? No good untill the computer/cam is gone. Track heat doesnt build lowend either.

The P heads stock springs are good to ~.520 lift I believe, but I aam not positive on that. Also those heads love compression. They have a very efficient combustion chamber and don't require a lot of timing for HP. So you can get away w/ more compression than you can on other iron heads.

The Comp cams ain't bad, but I wouldnt say they are anymore of a proven performer than the FMS series. No reason to ***** each other out over a messed up LSA.

Skyler

BTW, most morons at shops know nothing.

Last guy w/ a 700rwhp stang that touched my car said it put out 332rwhp hahaha, Unit you know the story behind this one!

Skyler

These guys are right, the Cobra cam is a POS.

As far as the P-heads. You're asking for trouble if you don't upgrade the valve springs. I know, I had to. The P-heads were made for the Explorer and Mountaineer. If you've ever driven a 5.0 Explorer you'll know they don't rev well past 5k, let alone 6k. I about died laughing after comparing my new springs with the factory springs.

I'd like to mill my heads for more compression, but I have hyperteuctic (spelling?) pistons. Anyone know how much compression these pistons can take?

Compression isnt a concern with hyper pistons, only power adders. Mill away.....

Not a bad idea to change them, but RPM and lift are too different things.

Skyler

I think 89 Cobra LX is trying to say that with the amount of lift and higher RPM's valve float will be inevitable. With better springs that problem will be fixed, well as long as she doesn't try to go to high. Hope this makes sense. Take it easy.

-Billy

The GT40 P heads have a max lift rating of .500. Just like the factory E7TE heads. Nothing wrong with the springs, they just aren't designed for high lift, neither is the head.

The GT-40P heads drop in flow after .500. Which means if you have a .533 lift cam, you're pushing beyond max flow. The P heads flow nearly the same at .400 as they do at .500.

Take a midline XE series cam. XE266HR. .544/.555. That's more lift than: TFS TW, GT-40, GT-40P, Windsor Jrs, etc allow. It may not run into piston to valve clearance problems due to the XE cam having poor duration. About the duration causing issues with the newer computers. First off, this isn't a newer computer controlled car. We're talking pre SN95. Second, it's not the duration the cars have issues with, it's the LSA. Roller cams have obvious advantages in any lift situations, especially high lift because their design allows them to work with much less friction. Friction isn't what I'm getting at here. I'm getting at work. It's a crapload of work to run a camshaft. When my belt broke on my 2.3L LX and I cranked the engine over, that starter was at least 1 1/2 times as fast. That's how much load the valvetrain puts on a starter cranking 200rpms. The more you lift, the more power loss you're going to have. Friction doesn't really enter into the equation, and neither does the roller cam since all the cams suggested are of the roller variety.

Like I stated before, the HO cam is a proven performer too. That doesn't mean it's a great choice for a performance cam. The XE series may perform better than stock, but at the cost of upgrading hundreds of dollars onto the parts that she has chosen. On a budget, with GT40P heads, the XE cam is junk.