#1:::Throw out all your Magazines that suggest what to do! Or, you could invest in a new set of heads that would also do the same job but you can expect to spend quite a bit more money. You can have your current 28 oz rebalanced to 50. We didn't increase the valve size, although we did have to add Manley valves to get the proper spring-installed height. I've not seen a set of longtubes that have an issue with GT40P's, either. Now he serves as a regular contributor to OnAllCylinders. With the GT-40P heads you will need to back off the timing a couple degrees and bump up the fuel pressure. GT-40 heads HP increase | Mustang Forums at StangNet I'm new and I'm currently building a 302 on a budget and want to raise compression without milling heads but by pistons and I want to get close to 10:1. Perhaps even more surprising was how well this engine idled, calmly purring with 16 inches of manifold vacuum at 980 rpm. Its increase while significant is still only about that of a decent 351 w, hi im building a nastalgic car so im not going to drag race it but it must go ok ive got a 302 windsor basicly recoed stock but i want to run tunnel rams to go with the the3am would like to put choppy cam and replace the heads any ideas would be much apprecited thankyou, What is the stock head cc of a 1992 f150 302 windsor. Different years can have different combustion chamber sizes but ffor the most part there will be no performance increases by going with 302 heads. Upgrading Fox Body Cylinder Heads - AmericanMuscle.com Consider having the head's intake ports matched to the intake manifold gasket. Not sure about that but got some pictures of the cast iron explorer manifolds on a 302. Dennis Hilliard of Central Coast says we can expect to gain three-tenths in the quarter-mile. Joined . 1986 Short block with notched pistons. fuel injection system . Stock Ford 351W 4bbl dyno numbers - Don Terrill's Speed-Talk HiPo manifolds and Ill be good. You didnt mention which cam you had in mind. Take the assembly to a machine shop to have it balanced and install it in the block. The multiple-layer steel construction allows the gasket to conform to movement between the cylinder head and block while maintaining a good seal. the springs are new stock oem ford. We've seen what happens from previous Ford experience when power levels above 500 hp tend to either pop head gaskets or saw blocks in half. They almost seem like flywheel numbers rather than RWHP numbers. Commonly referred to as Explorer heads, GT-40P iron castings are found on current 5.0-equipped Explorers. Performance & security by Cloudflare. i have a question once i get the gt40p heads from the explorer truck can i also take the exhaust manifolds or headers and fit them in my 66 mustang:?:!?!?!? I just read about this build on the corral.net. Required fields are marked *. If you dont feel comfortable doing this higher a pro. For a better experience, please enable JavaScript in your browser before proceeding. Car Craft mag. This pushed that little Ford to a peak horsepower of 503, and that was where we stopped. K.S. thats after 3 hours of idling/midrange hits to tune the idle and part throttle . Very true about finding them at the local yards. With the P-heads requiring pedestal-mount rockers, we also called up Crane Cams for a set of 1.6 pedestal-mount roller rockers. I am very happy too. $700.98. '85 GT vert two tone (white on charcoal)white leather, http://www.facebook.com/groups/233213650060739/, http://www.summitracing.com/parts/TFS-2500100/, ascMcLaren & Motorsport/Grand Prix IV Capris, RHD and Other International/Export Models, Mods, Maintenance & Mechanical FAQs/Archive, If this is your first visit, be sure to 1 - 7 of 7 Posts. The "P" heads flow better. Aside from the cost of the nitrous itself, this setup should cost you little more than a stock rebuild using all brand new parts. Someone does make the Tri-Y's headers for the early Mustangs using the "P" heads. I spin it to 6500 and thats about it. I recall having an absolute blast with my old K-code coupe back in the day. . In an effort to preserve the history of the Early Fox Era, FEP covers the following vehicles: 79-86 Mustang and Capri, 84-86 Mustang SVO, 78-83 Fairmont & Zephyr, 83-86 LTD & Marquis, 80-88 Thunderbird & Cougar, 82-87 Continental, 84-92 Mark VII, 81-82 Granada. Motor is going into a Ranger. Not bad for off the shelf parts and a stock shortblock. this is the price for one head. With gt40p heads and 289 hipo exhaust manifolds changing sparkplugs is the same as the original 302 heads and manifolds, I use the spark plugs that are recomended for the explorer with gt40p heads and you can use straight or angled boots. 68stang351 Founding Member May 16, 2002 850 There are a lot of variables that must be addressed to give a better estimate, but a good basic estimate is 20-40 HP at the crank. You will have to get special headers to fit these heads since the spark plugs are angled differently than normal 5.0 heads. .. i would not buy valves unless you need them amd would not switch to studs with these heads for your low hp . Vehicle: 1972 2 door 302 maverick, 1986 5.0 stang gt convertible,66 mustang coupe, HEMI ram. Gasoline/Diesel all makes on earth & still doing it today with great pride.Feel free to contact me anytime. The GT40P heads had a small combustion chamber ranging from 58-61cc while the GT40 heads had a 63-66cc combustion chamber. This is the main reason why these engines are not modified as much as the small block Chevy. Actually, making around 240 to 250 hp with a near-stock Windsor 302 will feel pretty good. Or just play it safe and let the fans ask away about another daring 5.0 TB bolt on or for an exciting surprise, do a LS______ fill in the blanks. Once the headers are in place, then you can consider if you still want more power. Install a set of 1.7:1 roller-tipped rocker arms on the heads. This is needed for the steel roller cam. 1979 Indy 500 Pace Car. I'm using the Trick Flow stage 1 cam with 1.7 roller rockers. Thanks for the help, I was planning on puttingin roller rockers or at least new springs, and that engine looks great, hoppfully mine will look at least similar to that one of these days. I'm sure the dyno operator used some goofball correction factor to make the numbers look higher. Yes Mr.Smith, your column here at OAC adorned with extreme performance without power adders, or all Engine as its known, from a superior pushrod Small Block featuring almost all USA sourced modern components with the familiar smell of Ford Blue. I view the GT40P heads similar to Granada brakes. They work, but present their own challenges. I am sure you have increased the bore size and possibly even the stroke a bit and spin it up pretty high in the RPM range. There was an article in Hot Rod magazine in the mid '80's where Jon Kaase was developing 351w packages. Purchase any used aftermarket manifold for the 302 that is designed to function in the 3,500 to 6,500 power band. 1985 Mustang GT Mild 331 4bbl 5 spd, 1985 SEFI LTD LX AOD. Calculating pushrod length Actually, making around 240 to 250 hp with a near-stock Windsor 302 will feel pretty good. These cast piston short-blocks are not quite as good as the forged piston 5.0L that came in Fox-body Mustangs, but the GT40P heads flow much better than earlier 5.0L heads. SB Ford GT40P Drop In Valve Springs Kit, Hyd Roller w/ Stock Cam, .450" lift and below. JUNKYARD GT40P HEADS-ADD 30+ HP TO YOUR 5.0L (FOR FREE?) For a better experience, please enable JavaScript in your browser before proceeding. I have a 302 Windsor V8 EFI engine that I converted to a 600 cfm carburetor with a Street Warrior intake manifold. In 1987, he assumed the role of editor for Hot Rod magazine before returning to his first love of writing technical stories. They are more expensive than standard head gaskets, but they also do the job and are worth the additional money. There are caveats to this plan, however. Depends on the budget. This needs to be removed and different exhaust valves, retainers, and valve springs added to turn this into a decent street head. Yea. The factory heads have a boss for the exhaust valve that restricts flow through the exhaust port. All manufactured using advanced CNC technology for the extreme durability and precision required of the modern canted valve Ford Small Block at power levels around the 1000 mark reached during recent competitions at the EMC and at the strip. Instructions on porting the GT-40p heads here. They suffered from poor aftermarket support up until about 15 years ago when it really came on strong. How to Build a Budget 383 Stroker Chevy How do I Increase Horsepower on a 440 Cylinder Head Specifications for a 1969 How to Get More Power Out of a 92 4.3 dragster engine image by Robert Young from, Copyright 2023 Leaf Group Ltd. / Leaf Group Media. If you're going to use the stock 289 heads, install 1.84-inch intake valves, then port the intake and exhaust; these mods will net you about 185 cfm of intake port flow at 0.50 lift. Both swaps made more sense when parts were readily available at the bone yard for cheap. If the head bolt holes are 1/2" or slightly larger, ARP makes the washers and can be sourced from Ford Racing or ARP through a speed shop or Summit, Jegs and PAW among others. Ford GT40P 302 5.0L 4 Bar Cylinder Head Assembly Pair w/ 1/2" Head Bolt Hole. You should be able to get away with a 150 to 200 horsepower shot later, but it's best to start out small and work up. As usual, there is much more to this story. This will cost additional money but is still worth it, in our opinion. Worst AFR 165 dyno ever | Factory Five Racing Forum The only one that's close, is #7. The GT40 and GT40P cylinder heads are highly sought after, but how do they stack up against other cylinder heads, and is it worth it to upgrade the Fox Body's stock heads? When compared to the new generation of performance engines on the market today like the 5.0L DOHC Coyote engine, your engine will not come close. What Cam and Springs to Use for GT40 Heads THANKS VERY MUCH! When you purchase through links on our site, we may earn an affiliate commission, which supports our community. Well offer one as an example. The engine was only rated at 215 hp, but it at least had 9.0:1 compression. Now we know why Dennis Hilliard of Central Coast Mustang is so high on these heads. Stock 93-95 Cobra shortblock (stock cobra cam), GT40X heads, 1.7 rockers, Edelbrock Performer RPM intake, Holley 650, and longtube headers. We compare the GT40s to modern cylinder heads as well as other heads from the era. The 302 uses smaller 7/16" head bolts and your "P" heads may or may not require the step washers. If you smooth out the bowls and exhaust ports and gasket match the intakes they should flow decent. how hard to put on? A forum community dedicated to Ford performance owners and enthusiasts. Never not once have I ever seen a SBF rod bolt create a failure. The Fora platform includes forum software by XenForo. JEGS High Performance. Their weak point is that the rotator used on the exhaust valve is very thick. It's a classic move we've pulled off many times. Ask Away! with Jeff Smith: Camshaft and Cylinder Head Recommendations Actually the regular gt40's in either aluminum or iron are the good ones but the gt40p's are only a slight improvement over regular 302 heads. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); This site uses Akismet to reduce spam. Compare. Ford Factory 5.0 Performance Cylinder Heads. . GT-40P Heads - 5.0 Mustang & Super Fords Magazine - MotorTrend (its not their engine) Yea. GT40P heads, what kind of performance do they give? The newer camshaft is designed for use with a soft bronze distributor gear, not the hardened steel gear used for older camshafts. Win or lose, if you buy the ticket you must take the ride. I went to a couple in Tucson and almost all the Ford vehicles that came with a 5.0 had the heads missing.