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Ford Performance Turbo-Swirl GT40X Aluminum Head - 64CC Chamber (82-85 5.0L; 87-95 5.0L)

AmericanMuscle no longer carries the Ford Performance Turbo-Swirl GT40X Aluminum Head - 64CC Chamber (82-85 5.0L; 87-95 5.0L). Please check out 1994-1998 Mustang Cylinder Heads & Valvetrain Components for an updated selection.
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Features, Video & Details

  • Bolt on 65 More Horsepower
  • Improved Air Flow Over Original GT-40 Heads
  • Combustion Chamber Volume 64cc
  • Intake Port Volume 178cc, Exhaust Port Volume 62cc
  • Lightweight Aluminum
  • Fully Assembled
  • Fits 1982-1985, 1987-1995 Windsor-Style 5.0L V8s
  • Sold Individually

Review & Installation Video

Review & Install Video

Hello and welcome back to Stage 3 of AmericanMuscle’s project Foxbody, as you can see we’re currently out enjoying the fruits of our labor which took place in the first two stages, and for the first time since we started this project, I can honestly say I’m not embarrassed to be out driving it. Of course a part of that lack of embarrassment is because we haven’t pulled up to anything fast yet, there’s no doubt our GT is looking good, but what’s the point of having all those Cobra parts if we don’t have the performance to back it all up, well, welcome to stage 3 my friends, where all of that is about to change. Before we get back to the shop where we lay out our plans to increase our tire slaying abilities, let’s recap what we knocked out in stage 2. In stage 2 we completely replaced our destroyed factory convertible top, with a brand new top and rear glass, along with just about every piece of molding and weather stripping you can think of, we put the finishing touches on our convertible Cobra vision, thanks to our Cobra tail light covers and 10th anniversary Cobra style wheels, made possible through the 5 lug conversion kit we installed. Finally, we moved to the interior and made it look as good as our exterior, thanks to the freshly painted dash, new carpet, and other miscellaneous items making our GT look and feel like it was 1993 all over again. Alright, I can’t wait to get back to the shop to show you all the stuff we have in store for this stage, let’s get to it. As you can see we have some big plans for our 302, all with the goal of replicating the Cobra’s power plant, which is going to drastically improve our performance. For starters, we’re going big with a trio of parts from Ford Racing, all of which will do wonders for our 5.0. First up we’re looking at the Turbo Swirl GT40X aluminum heads from Ford Racing, these heads are a variation on the original GT40 heads found on the 93 Cobra, with a few improvements. For one they’re made out of lightweight aluminum versus the heavier cast iron and they’re designed to flow much better than the original GT40’s. To top it off, we’ve installed some Cobra valve covers. For us to see the biggest gains using these heads, our stock cam just isn’t going to cut it, so we’re going to go with a popular street cam, the Ford Racing E303. This hydraulic roller cam should really compliment those GT40’s, and is an excellent choice for any street car thanks to its low to mid range torque. Of course we’re still going to have that great lope at idle which should sound amazing by the way, but it’s not radical enough that we’re going to have to worry about stalling out at every red light. The cheery on top for our 302 has to be this Ford Racing intake manifold, which is getting nearly impossible to find anymore, this part, paired with our Ford Racing heads and cam, is going to allow our 5.0 to flow some serious air, and will complete our Cobra transformation under the hood. Alright, in order to move all that extra air out of the engine, we’re reworking out entire exhaust from the headers all the way back, in order to keep up with that Ford Racing theme we’ve got going on under the hood, we selected our ceramic shorty headers, which we’d already installed when we did all of our motor work, and are designed to work specifically with those GT40 heads. From there, we go to BBK’s off road H pipe which does feature mandrel bent 2.5” stainless steel tubing, and should bolt up to those shorty headers without issue. Finally, everything’s going to exit out of Flowmaster’s American Thunder Cat-Back exhaust, which features those iconic 44 series mufflers. This exhaust features 100% stainless steel constructions throughout, including 2.5” mandrel bent tubing, and those OE style polished tips. Alright I think it’s safe to say we’ve got the performance side of things pretty well taken care of, but we haven’t addressed the fact that this thing still handles like a boat. So we’re going to attack our suspension much like we did our engine, go big or go home. Ron and I are just finishing up installing the KONI STR shocks and struts, which are actually a killer set for the price. We’re pairing those up with the SR Performance lowering springs, which should lower our Fox about an inch and a half on all 4 corners. Finally, we have the car in the air, the wheels off, we figured this would be a great time to ditch those rusty old drum brakes, in favor of these brand new disks. To dial in our new Fox’s alignment, we’ve installed the SR Performance caster/camber plates, which should get everything back into spec without issue, and offer a little bit more adjustment in future if need be. Since our car is a convertible, we are losing some of the structural rigidity which comes along with having a steel roof, to help combat this, we’ve installed the SR Performance subframe connectors, this part along with our springs, shocks and struts, should take all the laziness out of our suspension, and get it handling like a sports car should. Alright, now everything’s pretty much buttoned up, we’re going to tie it together with one of our custom Bama tunes, and see if all this hard work has paid off in really cranking up the power. We’ve already grabbed our baseline run after stage 1 when we got the car back from painting, so I’m going to hop in, bury this thing one more time, and see what the improvements are. Alright, our baseline run with our 93 GT gave us 194 horsepower, and 266 ft/lbs of torque. With all of our stage 3 modifications, the car put down an impressive 279 horsepower, and 317 ft/lbs of torque, making for a solid gain of 85 horsepower over our baseline numbers. The car did even better throughout the power band, picking up as much as 103 horsepower, and 107 ft/lbs of torque, throughout the curve. With the power finally there to back up our Cobra appearance, I think it’s time for one more cruise to see how our Fox does with all its modifications. Alright, stage 3, performance, check. The car's breathing better, the tune brought it all together, and as a result, this thing has some serious balls. Here we are, we’re in the back roads, moving along at a good clip, I’d saying the car is doing quite well, it’s pretty confident, I feel confident driving it, I don’t feel like I’m going to fly off the road, which I couldn’t have said before we did all this work. The car feels good, sounds awesome, and it’s just a whole hell of a lot more fun to drive. I know some people might question this build, you know, why a convertible, why a Fox body, well, because we wanted to, I mean that’s what car building is all about, it’s doing what you want. In this case, we’ve never seen Cobra convertible Fox bodies, so we wanted to build one, and I think we did a hell of a job. So is this the last you’ve seen of this car? I don’t know, maybe, maybe not, but in the meantime, thanks for watching stage 3 of AmericanMuscle’s project Fox body.

More Power. Increase the horsepower and torque output of your push rod 5.0L engine with the Ford Racing Turbo-Swirl GT40X Aluminum Head. These GT-40X heads feature a 64CC Combustion Chamber to greatly improve the airflow over the original GT-40 design allowing you to bolt on 65 more horsepower.

Improved Air Flow. These Ford Racing GT-40X heads have an intake port volume of 178cc allowing for an intake flow of approximately 240 cfm at .550" lift (at 28" of H20) and an exhaust port volume of 62cc allowing for an exhaust flow of approximately 170 cfm at .500" lift (at 28" of H20). Machined for 1.94" Intake and 1.54" exhaust valve diameters.

Lightweight. Made from high quality original equipment style 356-T6 aluminum castings, each head weighs in at only 22 lbs. that is 25 lbs. lighter than the original cast iron GT-40 head, that is a weight savings of 50 lbs.

Fully Assembled. Leak tested prior to assembly, each Ford Racing Turbo-Swirl GT40X Aluminum Head comes fully assembled with M-6507-J302 intake valves, M-6505-G302 exhaust valves, and M-6513-A50 valve springs. As an added bonus the valve springs are compatible with all Ford Racing roller camshafts.

Installation Notes. Ford racing "X" heads are designed to use either GT-40 or aftermarket performance intake manifolds, M9439A50 intake gasket, and AGSF-32C spark plugs. Designed for bolt-down rocker arms part number M-6564-B351 for a 1.6 ratio or use part number M-6564-A50 for a 1.7 ratio.

Application. The Ford Racing Turbo-Swirl GT40X Aluminum Head is designed to be a direct bolt-on for the 1982-1985 and 1987-1995 5.0L Windsor-style V8 engines. It will not fit 1986 5.0L with flat-top pistons unless pistons are notched for valve relief.

Technical Note. Be sure to check your intake manifold for port match, because not all intakes are compatible due to the tall high-flow ports.

Fitment: 1982 1983 1984 1985 1987 1988 1989 1990 1991 1992 1993 1994 1995 Details

MPN# M-6049-X306

CA Residents: WARNING: Cancer and Reproductive Harm -

What's in the Box
  • (1) Assembled cylinder head
Installation Info
Tech Specs
Will it fit my Mustang?
  • Cobra - 94, 95
  • Cobra R - 95
  • GT - 87, 88, 89, 90, 91, 92, 93, 94, 95
  • LX - 87, 88, 89, 90, 91, 92, 93
  • Other - 82, 83, 84, 85

Fits 5.0L Ford V8 engines. It will not fit 1986 5.0L with flat-top pistons unless pistons are notched for valve relief

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Questions & Answers (50)

5 Top Rated Questions

whats the difference between 58cc chamber and 64cc chamber?

  • The Ford Performance Turbo-Swirl GT40X Aluminum Head - 64CC Chamber features a 64cc combustion chamber. This is the area where the combustion cycle takes place, which is inside the cylinder the head. The Ford Performance Turbo-Swirl GT40X Aluminum Head - 58CC Chamber, item # 50542, ( features a 58cc combustion chamber.

Helpful (2)

Do I need an after market intake in order to successfully bolt on 65 horses? I'm looking to buy an expensive bolt on for my mustang. Either an intake manifold and throttle body or just plain aluminum heads. What is best for a stock engine? Thanks

  • If you are looking for 65 hp then get the heads they will add a good bit more hp the intake and throttle body will help with the heads but only about 15 to 20 hp the heads alone will be close to 65hp or more

Helpful (2) Show 2 more answers

Are these heads equipped with thermactor smog ports?

  • The Ford Performance Turbo-Swirl GT40X Aluminum Head will have Thermactor ports.

Helpful (1)

would this work im in search of new heads for my 88' gt and was curious if i could put the cobra intake and manifold on it ,it came with the car as extra parts not sure what it could possibly do or not do if i try

  • Yes, any gt40 intake will match up perfectly to these heads. You will need intake gasket part number 1262R.

Helpful (1)

will i have any issues as far as passing smog test or emissions with these heads?

  • The Ford Performance Turbo-Swirl GT40X Aluminum Heads do not have a C.A.R.B EO and therefore may not pass smog.

Helpful (0)
Post Your Question
10 More Questions
Will an Edelbrock Performer Intake Manifold 2121 fit with these heads? 1 answer
Hi. Will these heads work on a stock 89 gt lower Intake. Only reason I ask is bc my Kenne Bell is made for that lower intake and I don’t want to get rid of it. I would have the stock intake Ported to help out from choking the new heads down. 1 answer
would these heads be compatible with Edelbrock performer EFI intake manifold, This question needs to be answered yes or no 1 answer
Is this order only a pair or just one head? 1 answer
Would I need to change the pushrods if Im running a letter cam? 1 answer
I really want long tube headers...but not sure if HP wise, will give the same results as to the short headers that recommend for these heads. Can I get long tube headers, instead of short tube? 1 answer
Will these heads work with the stock cam and rods? And will it mess with the speed density meter? 1 answer
Will these heads fit my 1973 302 block? 1 answer
Will the turbo-swirl GT40x Aluminum head work for my 86 5.0. If i get the scat stroker series 9000 347 rotating assembly? Item #100932 because they have the valve reliefs? 1 answer
will this fit a 95 ford Thunderbird ? im not getting any clear answers on whats the difference between 95 t bird v8 and 95 stang plzz answer guros 1 answer

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Customer Reviews (15) Write a Review

Overall Rating 4.9

out of 5 stars

Installation Time:Full Day

Installation Cost:$500-$1000

  • Performance Gain 4.733333 4.7
  • Fit 4.933333 4.9

  • 5/5

    Installation Time: Less than 1 Hour

    September 26, 2017


    Fit very well! Looks great, lightweight vs the boat anchor iron! Can't wait to fire this baby up


    Year: 1990 Submodel: GT

    Helpful (9)

  • 5/5

    July 27, 2017

    Gt40x heads 64cc

    Good fit, ready to add the supercharger, and I'm already shredding tires brought out a lot of the low end torque and compliments my cam well


    Year: 1988 Submodel: GT

    Helpful (12)

  • 5/5

    May 31, 2017


    Exactly what I planned on, bolted right up no problem.


    Year: 1994 Submodel: GT

    Helpful (11)

  • 5/5

    Installation Time: Full Day

    May 24, 2017

    My heads

    Made a huge difference in the build!!! Way more power love them!!!!!!


    Year: 1995 Submodel: GT

    Helpful (12)

  • 5/5

    Installation Time: Weekend

    July 01, 2016


    Great quality Ford product, fit and finish just like they came on car from factory. Great PAC springs that will work with most every camshaft excluding crazy big cams. Big combustion chambers great for forced induction cars. If staying N/A recommend getting 58cc to keep compression up. Flow devent, not best but I prefer genuine Ford Parts. Would definitely buy again. Fast delivery as with all AM parts.


    Year: 1993 Submodel: Cobra

    Helpful (12)

  • 5/5

    Installation Time: Afternoon

    June 08, 2016

    Upgrade hp

    My head gasket recently blew! So instead of just cleaning it up and replacing the gaskets And possibly paying to machine the stock boat anchors.I decided to spend the extra money and go for a weight reduction and hp gain and yes it worked out! They look great and I can feel the extra ponies when I hit the gas!


    Year: 1982 Submodel: GT

    Helpful (9)

  • 5/5

    Installation Time: Shop Install

    Installation Cost: $500-$1000

    December 12, 2014

    Would I reccomend? Yes and No

    Silky smooth install. Good quality parts. If you do not plan on porting these heads I would recomend going with the Edelbrocks that AM offers. Although they are a little more expensive they flow much better on paper. With that being said I think these heads flow excellent. I can hear the difference in air that my engine gets now. If I could go back in time I would order these heads again


    Year: 1995 Submodel: GT bay area

    Helpful (12)

  • 5/5

    Installation Time: Full Day

    June 22, 2014

    Great fit

    This heads arrived insanely fast. I think it was like two days. And wow what a difference these made!


    Year: 1988 Submodel: Other Redding, CA, USA

    Helpful (10)

  • 5/5

    Installation Time: Afternoon

    May 08, 2014

    Very nice setup

    I read tons of reviews and forum discussions but it came down to price for me I bought one head new and the other new but open package on Ebay and for about $700 I have a set of aluminum heads that blow away the stock anchors. I havent had the car out for a full pass yet but sure does seem a lot more alive I do want to mention that the chambers needed some cleaning up any novice can do it I have porting experience and the tools but just gave them a quicky.


    Year: 1990 Submodel: Other Long Island, New York, USA

    Helpful (11)

  • 4/5

    Installation Time: Weekend

    January 24, 2014

    Finishing off the top end

    Installed in about a weekend. everything fit nicely. Only negative comment is the packaging for an expensive machine piece the packaging left a lot of opportunity for damage in shipping.


    Year: 1991 Submodel: GT

    Helpful (10)

  • 5/5

    Installation Time: Shop Install

    Installation Cost: $250-$500

    December 20, 2013

    great pricing

    the web site was easy to use and the pricing was great. not installed yet doing a whole engine rebuild this spring. looking forward to breathing more life and power into my car.


    Year: 1995 Submodel: GT Oklahoma City, OK, USA

    Helpful (11)

  • 5/5

    Installation Time: Afternoon

    April 26, 2013

    more than expected!!!!

    I was expecting some heads to arrive that were as heavy as the stock heads and that would perform a little better than stock. man was I wrong. these gt40x heads weigh half as much as stock and way out perform them. along with the ford racing e303 cam and shorty headers in saw a 115 rwhp gain on the dyno. the icing on the cake is that now my stang just sounds meaner than ever.


    Year: 1993 Submodel: GT vidalia, GA

    Helpful (18)

  • 5/5

    Installation Time: Weekend

    March 21, 2013

    Great heads for the money!

    I make over 450 HP at the wheels using these heads on my 110,000 original 302 with a procharger P1SC, F Cam and GT40 intake.


    Year: 1992 Submodel: GT Dayton, OH, USA

    Helpful (15)

  • 5/5

    July 11, 2012

    roller rockers

    you will need 1.60 PEDESTAL roller rockers to fit.


    Year: 1995 Submodel: GT Sarasota, FL, USA

    Helpful (22)

  • 5/5

    Installation Time: Less than 1 Hour

    March 16, 2012

    Fresh Build, Clean Power

    Ordered through a local ford shop. Shipped quicker than "All" the competition. Clean Fit, awesome detail done by ford racing and even weighs less than the v6 cast aluminum heads. These heads are awesome!!!


    Year: 1998 Submodel: Other Hampton, Va

    Helpful (17)

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