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2-8-1
07-29-2007, 12:26 AM
So, What makes a 1995 Cobra, horsepower wise, better than the GT. I know they have 20 more hp or so, but what is changed for them to get it, I know the intake flows a little better, but is that the only change?

Thanks

Aaron

331TwistedWedge
07-29-2007, 12:29 AM
they have gt40 heads, the cam is different (i think its a b cam) and of course the intake ... 24lb injectors to feed the extra air ...

PaulFiveOh
07-29-2007, 12:39 AM
Hey great question....

I wont lie, until now, I didn't know where my GT40 heads came from :)

2-8-1
07-29-2007, 01:06 AM
So, would it be beneficial to get GT40P heads and the matching intake over the stock GT40 and Cobra intake? What about a cam to compliment?

331TwistedWedge
07-29-2007, 01:25 AM
So, would it be beneficial to get GT40P heads and the matching intake over the stock GT40 and Cobra intake? What about a cam to compliment?

they are both very similar in performance, the gt40p heads and explorer intake are significantly cheaper ... not sure on the best cam for this combo ~ i personally never used this combo, but others on the board have ... maybe they will see your post and chime in ...

2-8-1
07-29-2007, 10:42 AM
I actually found some flow charts late last night/early this morning. The GT40P heads flow significantly more "under the curve" I honestly think that in a side by side road test, the GT40P heads should pull the GT40 heads in midrange fairly well. At least on paper they should. Peak Flow was about the same though.

I still really don't know anything about the pushrod cars, so please chime in and tell me whats going on. I'm looking at a 1995 Cobra right now, so any help is GREATLY appreciated.

On that note, anyone know what a 1995 Cobra with 135,XXX Miles and Basic Bolt ons, that has been well taken care of is worth?

331TwistedWedge
07-29-2007, 11:17 AM
i would guess around $5000 - $6500 with those kind of miles ... one just sold on ebay for $12000, but it had 20k miles ...

if you can get a decent price on the car, take it! ...

take it for a test drive, put a few miles on it and make sure everything is ok :bigthumb

they are nice cars, smoother than a fox ... easy cars to get running decent ... good luck ...

2-8-1
07-29-2007, 12:21 PM
Ive driven it before, Its as solid as one could expect. A friend of mine has it. I offered $4500 cash for it, and I'm willing to go to 5K.

It has a bodykit and all that on it, so If I get the car, the kit and hood and wheels and all will be for sale.

85_SS_302_Coupe
07-29-2007, 01:38 PM
They're essentially the same engine as the '93 Cobra, which i believe had the up and coming '94 V8 Thunderbird computer and cam to counteract the heads to meet emissions. I remember a lot of guys would swap in regular HO 5.0 cams and computers and pick up a few horses. As for being a B cam i really don't think so because those cams have a pretty significant lope and i've never heard a stock Cobra with a lope.


As for P vs. non P, the reason the P's have the revised spark plug angle is to provide a more "center of the cylinder" spark which burns fuel more efficiently and therefor aids in power. Also as i mentioned in the other thread i believe there's a combustion chamber difference and i think it's the P's that have smaller bowls so you'd have better compression with the Ps.

I can't say much about the intakes as i'm not that knowledgeable about EFI.



Here ya go....this is a really good site for referencing info like this. http://www.jason.fletcher.net/tech/flowdata/castiron.htm

As you can see, the GT40s have slightly different valves, coming in at 1.84/1.54, whereas the P's have 1.84/1/46's. The smaller exhaust port probably increases port velocity which would explain the difference in flow at .500 lift. The differences aren't enormous but like mentioned above the simple fact that P's are easier to come by than non-P's is all the more reason to use them. The only issue is the headers but that can be solved with the right set of headers.

2-8-1
07-29-2007, 02:04 PM
thanks guys, and thanks for the link

anything else I should know?

85_SS_302_Coupe
07-29-2007, 02:34 PM
Well i didn't see it mentioned in this thread yet, but there are header issues with the P heads because the spark plugs almost stick straight out from the head and come in contact with most headers. Ford sells their own headers that get around this, but a lot of people run Mac full lengths because they clear the spark plug. Lots of full lengths will work because of how the primaries shoot straight out from the head, but shorties are really a hit and miss.

2-8-1
07-29-2007, 04:48 PM
Ive heard that. Is there any real difference in the routing of Longtubes on a SN95 from a Foxbody?

85_SS_302_Coupe
07-29-2007, 09:34 PM
Ive heard that. Is there any real difference in the routing of Longtubes on a SN95 from a Foxbody?

I really can't say man...pretty much all my knowledge is on '79-93 (and it aint too much..lol). All i'm sure about is how the headers come out from the heads because of the plugs.

RACEME
07-30-2007, 05:40 AM
The main difference on the headers is that the 94-95 ones have an egr tube on the passenger header that goes up to the egr valve on the intake. The 86-93 models have the egr stuff internal in the intake. Corral, and Stangnet have 94-95 specific info on these cars.

Timido
07-30-2007, 05:57 AM
I dont think there is enoough difference that you could tell between gt40 and gt40p heads. If you want to spend money get a better head or have the gt40s ported and a valve job done.

2-8-1
07-30-2007, 06:19 PM
I have a 1996 Ford Explorer 5.0 Liter engine. Just wondering if it was worth switching everything over. If/When I get the car.

RACEME
07-31-2007, 05:38 AM
I would not switch from regular heads to the "p"s. The "P"s take a special header due to that spark plug angle. I would either step up to alum heads or port the gt40's, upgrade the springs and get a bit more agressive cam in it.