First mod will be GT40, help a newbie out

[putertopia]

I just bought a 95 GT and I think I want to the GT40 head/intake conversion for my first mod. Also want to throw a cam in there, but I want to keep this car acceptable for every day street use.

I'm a mod noob, I've never dived into performance. All I want is a simple list of what items are needed to make this conversion happen, and maybe a ballpark cost figure. I guess the part I'm most worried about is the computer considering my car is a 95. Am I going to have to get a custom computer done up for my car? What about injectors, are the stockers fine? If you can find a thread that has the list of materials, please post it. I didn't have any luck finding any, although I'm sure there are considering how many threads there are pertaining to this subject. The work itself I can handle, I'm not stranger to being under the hood, I've just never gotten into performance modifications.

As for right now, current mods to my knowledge are b&m short throw shifter, flowmaster full exhaust, no cats, BBK h-pipe, msd blaster coil, BBK fenderwell intake, 3.73 posi rear end, BBK adjustable FPR, BBK 70 MM throttle body, and air-fuel gauge.

Any other mods you would suggest to complement this? Or any mods to do before I get the GT40 to throw on a few extra ponies?

I don't want to be the classic newbie that asks what he can do to make his car faster when there's already so much information out there, I just want some guidance. Thanks!

- Josh

 

[302GTS]

Let's see the car! Sounds like a great starting platform! As for the GT40 swap, I havn't done anything like that, so hopefully someone will chime in with more knowledge. As for the computer, you should be perfectly fine, as I believe that the Cobras came with the same computer as our GT's did. I could be wrong though!

 

[LethalInjection]

Ok, GT40 setup on a street car makes wonderful power in the rpm range most often seen on the street. Very torquey and a brute from a stoplight. Price is going to depend on what parts you want. Here's a little info on the parts, you decide what you want and get back to me.

Intakes:

1) Original tubular GT40 intake - EXPENSIVE Makes wonderful power, very attractive to the eye. Upper doesn't allow for porting down the road.

2) Cobra intake - Cheaper than the above and more available. Cast version of the GT40. Makes almost identical power. I also am a fan of the way it looks. Upper can be cut, ported, and welded if your future plans go more extreme. Also comes in the 94-95 version with built in elbow.

3) Explorer intake - Cheapest. Fairly easy to find. Came on 5.0l explorers. Also cast version of GT40. Not as appealing to the eyes, but also makes almost identical power. Some ppl say the plenum design distributes air from TB opening better. Upper can be cut, ported, and welded.



Heads:


There are 2 versions of the cast iron GT40 castings.

1) The traditional GT40's found on cobras, 351 based lightnings, and pre 98 5.0L explorers.

2) Then there are the GT40P's found on 98+ 5.0L explorers. These have rotated spark plugs to unshroud the valves, smaller combustion chambers for more compression, and a redesigned exhaust port that utilitzes a slightly smaller valve yet flows more. They are very efficient heads that will make a bit more power than the standard GT40's however they require a valve spring upgrade to run a bigger camshaft as well as special headers to clear the rotated spark plugs. Some headers work and some don't. Most longtubes do. Other than that it's a luck of the draw. They are usually initially cheaper to buy as well.


Cam:

There are many. We will discuss these options once you have a specific intake, heads, and computer tuning options picked out.



Computer:
The computers for a 5spd, auto, and cobra are all different. I'll not go into these differences at the moment, but will tell you I would wait until you get your Heads, cam, and intake up and running with supporting hardware, and then get it dyno tuned.

 

[Adam95GT]

it all depends on what you do for a cam... in any case if you have the money you should get a tune... u could always go with a cobra cam... cobra ecu and 24lb injectors

 

[Labora]

If you have the budget for it, get some aftermarket heads! (And a cam that matches.) Changing the intake later is cake.

Anyhow in respect to your OP, Lethal seems to have it pretty much covered.

Some may say you need a dyno tune, but if you can get your hands on a Cobra ECU a pair of injectors and possibly a MAF you would be set. And from my dealings the Cobra ECU is much more forgiving to mods, and even a cam then the 94-95 GT computer. (I know this sort of stuff varies car to car thou, my setup has had the good fortune of having all new sensors which I'm sure helps.) If you plan to change things up much later, or even run a power added a more powerful ECU may be the way to go.

Also don't forget to factor in small stuff into you budget. Such as head bolts, gaskets, head rebuild/valve springs, etc.

 

[Mr_302]

Intakes:

1) Original tubular GT40 intake - EXPENSIVE Makes wonderful power, very attractive to the eye. Upper doesn't allow for porting down the road.

2) Cobra intake - Cheaper than the above and more available. Cast version of the GT40. Makes almost identical power. I also am a fan of the way it looks. Upper can be cut, ported, and welded if your future plans go more extreme. Also comes in the 94-95 version with built in elbow.

3) Explorer intake - Cheapest. Fairly easy to find. Came on 5.0l explorers. Also cast version of GT40. Not as appealing to the eyes, but also makes almost identical power. Some ppl say the plenum design distributes air from TB opening better. Upper can be cut, ported, and welded.



I cant find the thread i put it on but i had this question in my head and now its finally answered thank you

I'm in the same sea fairing vessle (boat) as the other guy. And im certain that im gonig to go with the exploer intake do the the availbilty and the price. on ebay for dirt cheap comapre to the cobra on i was going to buy that i had to get the elbow for becuse it was off of a 93 model.
what do i need to know if i go with the explorer

meant to quote that first part

 

[LethalInjection]

If you have the budget for it, get some aftermarket heads! (And a cam that matches.) Changing the intake later is cake.

Anyhow in respect to your OP, Lethal seems to have it pretty much covered.

Some may say you need a dyno tune, but if you can get your hands on a Cobra ECU a pair of injectors and possibly a MAF you would be set. And from my dealings the Cobra ECU is much more forgiving to mods, and even a cam then the 94-95 GT computer. (I know this sort of stuff varies car to car thou, my setup has had the good fortune of having all new sensors which I'm sure helps.) If you plan to change things up much later, or even run a power added a more powerful ECU may be the way to go.

Also don't forget to factor in small stuff into you budget. Such as head bolts, gaskets, head rebuild/valve springs, etc.

I believe the MAF on the 94-95's is the same for the GT and Cobra. They are both 70mm units. The calibration for the 24lb injectors is inside the Cobra (J4J1) computer. If he could come across the cobra processor cheap then that would WORK with the 24lb'ers, but it would probably be more cost efficient and overall better to go with a mail order chip for his GT processor taylored to his mods. A dyno tuned chip would be best, but more expensive due to the dyno time.

 

[LethalInjection]

Intakes:


I cant find the thread i put it on but i had this question in my head and now its finally answered thank you

I'm in the same sea fairing vessle (boat) as the other guy. And im certain that im gonig to go with the exploer intake do the the availbilty and the price. on ebay for dirt cheap comapre to the cobra on i was going to buy that i had to get the elbow for becuse it was off of a 93 model.
what do i need to know if i go with the explorer

meant to quote that first part

You'll need to get the 94-95 mustang intake elbow in order to run the 94-95 throttle body and throttle linkage setup. That's pretty much the same for all non OEM intakes for the 94-95's though. Of course the 94-95 Cobra intake has it built in, but the elbow is required for all others.

 

[LethalInjection]

it all depends on what you do for a cam... in any case if you have the money you should get a tune... u could always go with a cobra cam... cobra ecu and 24lb injectors

Don't forget the cobra cam was somewhat whimpy. It has some pretty small duration times and wide LSA. Duration and LSA help with cylinder filling and increase power along with duration shifting your powerband up. Also, the cobra's lift numbers are on a 1.7 ratio rocker arm so take the lift divide it by 1.7 and multiply that number by the 1.6 ratio of the rocker arms on the stock GT's and you are close to the stock GT cam. However a very popular cam with the SN95 crowd with GT40 heads is the Trickflow Stage 1. I am personally swapping my B cam out for something a little more aggressive than the TFS1. I have some work in my heads and intake and my computer takes well to being monkeyed with though.