Gt500 cams on 03/04 dohc heads

IUP99snake

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I saw a pretty sweet deal on a set of gt500 cams (same as the GT supercar) and was thinking it might be a good upgrade over the stock 03/04 cams that came with the heads I have.

Is this a worthwhile upgrade? All I'm looking for is just a little more power throughout the powerband. I don't expect or want my car to lope and shake like it would do with aggressive aftermarket cams.

If these arent the best factory cams, what are?
 

98fourvalve

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I was under the impression that the Gt cams were not a good upgrade.

I'd check into some 96-98 Cobra Intake cams.
 

01yellercobra

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What year GT500 were they out of? AFAIK they didn't start putting the Ford GT cams in until 2013. I remember hearing about the earlier model GT500's switching over to the GT cams. It's not a bolt in deal. The springs need to be changed as well. I have the GT cams in my motor. My thinking was they would work better then the stock cams since they were designed for a 5.4. As of right now my power falls off a little past 6K. But I think that has more to do with the stock intake then the cams.
 

fastback brian

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for the most part gt500 cams are the same as 03-04 cobra cams, not sure about the 12-13's...99- 01 cobra cams are one the better factory cams. but maybe the application, like a blower setup, may like the smaller gt500 cams..:shrug:
 

Bmeagher

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2013 gt500 cams would be totally different from the earlier models because of the vct's. 2012 and lower don't run phasers.
 

IUP99snake

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2013 gt500 cams would be totally different from the earlier models because of the vct's. 2012 and lower don't run phasers.

The 2013 GT500 doesn't have variable cam timing. I know Ford says it does in an online spec sheet, but it's a typo.

The GT500 5.8 is not a coyote-style engine. It's basically just a big bore 5.4 modular 4V motor. It has the same basic type of DOHC heads that have been used on any 4.6 or 5.4 when Ford switched over to the "tumble port" heads in 1999. I'm not saying all DOHC heads are the same since 1999, but they are all, for the most part, interchangeable with minor exceptions with intake and exhaust ports.

If you look at a picture of the GT500 engine and compare it to a coyote style motor, you'll notice that the valve covers look the same as any other DOHC modular motor, as opposed to the coyote style motors that have more compact heads.

2013-Ford-Shelby-GT500-5.8L-V8.jpg


If it did have VCT, there would be two wiring harnesses that plug into the front of each head to control the phasers.

coyote%20in%20a%20fox%20m-6007-m50.jpg


See the two plugs in the front of each head?

It would be pretty sweet if they made a 5.8 version of the coyote, perhaps a "tall deck" motor like the 5.4 (or 5.8) is to the 4.6. But for the time being, I'm happy they're keeping the old design going because that means more parts are interchangeable with my setup.
 

Ironhand

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I saw a pretty sweet deal on a set of gt500 cams (same as the GT supercar) and was thinking it might be a good upgrade over the stock 03/04 cams that came with the heads I have.

Is this a worthwhile upgrade? All I'm looking for is just a little more power throughout the powerband. I don't expect or want my car to lope and shake like it would do with aggressive aftermarket cams.

If these arent the best factory cams, what are?

03-04 Cobra, Mach 1, 07-12 GT-500, aviator, Navigator all use the same cams.

The 13 GT-500 used FGT profiles.

The best factory cams are 00R cams. 212/212 .515/.468.
 

na svt

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The GT cams have only 197 deg duration and are a downgrade to the 99 cams which have 202 deg duration. The 96-98 cobra cams have 204 deg duration but will only provide minimal gains over the 99 cams. The Cobra R cams do have more duration but the also require new valve springs because of their higher lift.

The 5.8 as stated earlier does not have variable cam timing.

It's not a bolt in deal. The springs need to be changed as well. I have the GT cams in my motor. My thinking was they would work better then the stock cams since they were designed for a 5.4. As of right now my power falls off a little past 6K. But I think that has more to do with the stock intake then the cams.

GT cams can be used with stock valve springs. Also, the power on any n/a combo with a stock intake manifold will fall off at 6200, regardless of the camshaft's duration.
03-04 Cobra, Mach 1, 07-12 GT-500, aviator, Navigator all use the same cams.

The 13 GT-500 used FGT profiles.

The 2011 GT500 has the GT cams, prior to that they used same cams as all 03/04 4.6s (Mach, Aviator, Marauder and Cobra) and also all 4v Navigators.
 
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Ironhand

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The GT cams have only 197 deg duration and are a downgrade to the 99 cams which have 202 deg duration. The 96-98 cobra cams have 204 deg duration but will only provide minimal gains over the 99 cams. The Cobra R cams do have more duration but the also require new valve springs because of their higher lift.

The 5.8 as stated earlier does not have variable cam timing.



GT cams can be used with stock valve springs. Also, the power on any n/a combo with a stock intake manifold will fall off at 6200, regardless of the camshaft's duration.


The 2011 GT500 has the GT cams, prior to that they used same cams as all 03/04 4.6s (Mach, Aviator, Marauder and Cobra) and also all 4v Navigators.

I remember that now. Early morning brain fart. lol
 

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