MM&FF Compare Stock 03 Cobra Term, 05 GT, & GT500 w\ KB SC @ 20psi
 

It's a pretty cool\interesting article. A good one to go over while eating lunch at work or what not.

Anyways, it's a stock '03 Cobra Terminator, stock* 05'GT, and stock GT500 (unspecified year). They added a Kenne Bell 2.8L Twin Screw Super Charger to each, and pushed put 20psi.

*It should be noted that the '05 GT isn't entirely stock.

From the article; While both the Cobra and the GT500 sport four valves per cylinder, don't count out the little Three-Valve motor. What it lacks in displacement or valve count, it makes up for in static compression and variable cam timing. These attributes aren't shared by the Four-Valve contingent, but it must be stressed that the stock Three-Valve rotating assembly wouldn't stand up to the abuse of 20 psi of twin-screw boost without modifications. Given the missing eight valves and normally aspirated origins, we decided to help out the Three-Valve GT motor with a boost-friendly rotating assembly. In went a Cobra crank, forged rods, and stock-compression pistons courtesy of Sean Hyland Motorsport that would allow us to safely crank up the boost on the Kenne Bell blower.

Also, all three were equipped with Bassani after-cat exhaust systems.

The Results:

The GT500

With 20 psi registered on the boost gauge, the 5.4L GT500 belted out 756 hp at 6,200 rpm and 684 lb-ft at 4,800 rpm.



The Cobra

With 20 psi registered on the boost gauge, the 4.6L Four-Valve motor produced 702 hp at 6,700 rpm and 578 lb-ft at 4,900 rpm.



The 05 GT

With 20 psi registered on the boost gauge, the 4.6L Three-Valve motor produced 704 hp at 6,500 rpm and 607 lb-ft at 4700 rpm. The higher compression and variable cam timing more than made up for the missing valve.


http://www.musclemustangfastfords.co...out/index.html

Since the article is about the differences in the power outputs after just throwing on the 2.8l KB, I'd have liked to have seen the GT stock to see how the little 3v compares to it's 4v siblings stock for stock. But overall neat article.

Probably would have been about the same, they didn't do any cam work or anything like that, basically just beefed up the internals to accomodate for the added stress. It's pretty impressive that the 3 valve actually out-performs the Terminator setup...

Would of been pretty impossible to push that kinda power on a stock bottom end of a 3v. Besides they kept it stock compression and no other mods so its a fair comparison.

I'm not surprised the 3v did so well as they always said the 3v heads are just as good at the 4v heads.

The 3v's torque is very impressive compared to the 4v 4.6 considering it comes 200rpms lower and is 30 ft lbs higher



to be fair you can't really compete with an extra 800cc under the same boost but damn does it try

Yeah it's definitely a fair comparison. They didn't modify the internals to perform better, only to handle the increased load.

thats pretty cool to see the 3v out do the cobra.

but in mod cost, your out more on the 3v. and alot more work, whereas the cobra is bolt on. and a dyno i guess. im not sure on boosting.

that is a very true thing to consider.

I know it would somewhat defeat the purpose but I would love to see how a 2v with the new Trick Flow heads would stack up against the 3v and 4v cars.

Were gonna find out soon enough what a TF headed 2v car can do.

depends on how much you are getting a 05+ GT for or a 03-04 cobra for. Price could be similar.

its still not bolt on! =)