This is a function of the somewhat wider lobe-separation angle of 112 degrees. (Image/Harrison Creamery). Seriously though if you're not planning on an all-out attack for HP, I'd consider a forged piston out of Probe's SRS line-up. . THANKS VERY MUCH! The factory heads have a boss for the exhaust valve that restricts flow through the exhaust port. I'd much rather be able to drive it at 8 or 9/10s of what it can handle. The GT40 heads are a bit more versatile, working with the 5.4 and 6.8, while the GT40P (Explorer/Mountaineer) heads will only work on the 6.8 due to an interference issue. Sponsored. Shop by category. Without changing the stock pistons. 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. . Pride is built, in your garage, with your two hands. Shop by category. They almost seem like flywheel numbers rather than RWHP numbers. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); This site uses Akismet to reduce spam. The entire front accessory drive and timing chain cover must be removed, along with the distributor and intake manifold. Very true about finding them at the local yards. Not to mention, they will run circles around GT40P's out of the box. I used Lightning heads on my 302, (GT40 not P) with stock rockers on a flat tappet engine. This combination should be good for about 400 horsepower and as much as 500 if you opt to use the stronger aftermarket pistons. Come join the discussion about performance, production numbers, VIN decoders, modifications, troubleshooting, power adders, DIY tutorials, and more! I spin it to 6500 and thats about it. Adding the headers may also require a slight increase in secondary (and possibly primary) jetting to ensure the proper air-fuel ratio, but thats also an easy tuning change. $700.98. Not *as* good as the GT40p heads, but I'd prefer to not have to worry about exhaust fitment issues, or have a narrow range of what I can work with. One benefit gt40P head will have over other 80's-90's model heads, including the gt40 head, is that it has a smaller combustion chamber much like the original 289 heads. Take the assembly to a machine shop to have it balanced and install it in the block. If you can find individual flanged headers like the obsolete MAC headers had, those worked really well with GT40P's. That carbureted GT40P motor made 465 on th engine dyno with a .500" 239/244 camshaft, Holley 650 carb and Weiand Stealth intake. Choose a cylinder head before you install the pistons. So . Horse Sense: The smaller valves found in GT-40P heads improve airflow velocity. This pushed that little Ford to a peak horsepower of 503, and that was where we stopped. However there are plenty of factory heads that with the help of an experienced machine shop can be great. Where they differ is the combustion chamber size. The reason this new generation of Ford engines make a ton more power is they also enjoy fantastic cylinder heads and four valves per cylinder. Find many great new & used options and get the best deals for FORD GT40p 4 BAR HEADS IN GOOD CONDITION w/ONE BOLT BROKEN at the best online prices at eBay! Performance & security by Cloudflare. I got a GT40P off the assembly line years ago. (A starter is a motor, windshield wipers use a motor,electric windows use motors) Any one uses that terminology in my shop will be corrected once, only once. You need to check. Slover primarily focused on the exhaust side of the GT40P heads. You didnt mention the car this engine is in, but lets assume there is enough room to remove the radiator and any other coolers and perhaps some or all of the front grille and/or brackets before the cam has sufficient room to exit the front of the engine. If I get different urges later, Ill pursue those then. this is the price for one head. The rest went very smoothly, and we reused the stock lifters and suffered no ulcers worrying about breaking in the cam. Features hardened 4140 Chromoly retainers, valve locks, spring shims, a spring height gauge, valve seals, and instructions. I wouldnt recommend reusing lifters though. '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 The older pushrod engines just dont offer the same kind of power potential for their displacement and it all has to do with cylinder head flow. That's an improvement of 22 hp over Test 2. Test 1: 750-cfm carburetor, dual-plane intake manifold, and stock camshaft. If you dont feel comfortable doing this higher a pro. The 2 heads are about the same when looking at the numbers with the GT40p heads having a slight edge. You gave me the info I was looking for, and I really do appreciate it. Car Craft mag. We were cruising the 'yard a while back and located a 2000 Ford Explorer with an EFI 5.0L V-8 engine. The gt40p head is considered the best OEM 302 head made. 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. Common sense would suggest that with the heavy lifting complete and the old cam removed, by not installing the new roller lifters along with the camshaft could be asking for the possibility of trouble just a few thousand miles down the road. However, stepping up in the performance head market will set you back more than $1,200 for a decent pair of aluminum castings--and that's straight out of the box, with no porting. Despite adding 30 degrees of intake duration, this cam improved torque throughout the entire test from 3,000 rpm on up. I am very happy too. i've got a short block started, and i recently came across a set of GT40P heads for FREE ( love family members). Test 2: Changed to the smaller of the two Lunati camshaftsno other changes. Install a used set of 5.0L Mustang "shorty" headers, generally available at auto swap meets for a reasonable price. Holten's best time is a 12.63 at 105.9 mph, and if we gain the desired result he will be right in the thick of things in Trophy Stock competition. The reply has so many assumptions that I cant even assume to know the answer. bmcdaniel, Feb 17, 2004 #7. v8maverick Member. These are Ford iron GT-40P heads. Richard Holdener 240K subscribers Subscribe 63K views 1 year ago WESTECH PERFORMANCE GROUP LOW BUCK, GT40P 5.0L HEADS-CHEAP &. Similar to regular GT-40 heads, the biggest difference between the two is that the P-heads feature a revised spark plug angle which extends the plug into the combustion chamber, putting the flame front close to the absolute center of the chamber, resulting in a smoother combustion process. He'd be the best source. the springs are new stock oem ford. GT40, GT40P, would be great factory heads. I'm wondering how these heads will interact with the paxton 1220 sl supercharger I'm trying to put on. Don't let the fact that the iron GT40 heads have a larger exhaust valve fool you. Stock heads with a fresh 3-angle valve job, shorty headers, T5, 4.10s, stock Explorer intake and stock '88 GT short block with 140,000 miles on it and an E cam in it. Obviously, tuneups will vary. 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. The best thing to do would be to use a specific break-in oil for the first 200 to 300 miles of use to reduce the change of a potential problem with undue wear. There was an article in Hot Rod magazine in the mid '80's where Jon Kaase was developing 351w packages. $169.50. They are more expensive than standard head gaskets, but they also do the job and are worth the additional money. This is a common mistake with first-time cam buyers who dont necessarily appreciate that the cam is just one component of the overall engine package. Eldelbrocks Air Gap intake manifold should work well with the combination. The SUV indicated barely 120,000 on the clock, and after yanking the valve covers to judge the engine's condition, Tim Moore instantly made the decision to do the boneyard version of a smash-and-grab. I think one of the finer traits of a true car guy, is the patience to put a prized car away and just let it sit for a while rather than selling it when life gets in the way. A solid 300-325 hp should be plenty and that's with good drivability and reliability as well. Even with relatively small valve sizes of 1.85-inch intake and 1.46-inch exhaust, the P-heads flow much better than previous. LOW-BUCK 302 FORD HEAD UPGRADE Richard Holdener 239K subscribers 189K views 2 years ago WESTECH PERFORMANCE GROUP WHAT'S IT WORTH? Assemble the rotating assembly with a stock 5.0L crankshaft, a set of 5.0L rods and the specified pistons with stock-type rings. MAC is the only manufacturer of these headers, and the parts we installed fit like a glove with no problems whatsoever. Best of all, no machining is required to install these on your stock cast iron heads! Start with any 302 block, but try to find one from 1985 and up since it will already have provisions for a roller camshaft. 302 explorer short block with roughly 80k miles GT40's from a local u pull n pay ($97) weiand x-celerator trick flow stage 1 cam 650 holley double pumper car made 322/329 SAE . The only way to really make more power is to go with a stroker kit, blower and/or heads. Nice to see actual dyno results instead of "butt dyno" guesses. Per a UEM tech support email I have the Icon IC736 is supposed to be good for GT40 heads when I asked about it. I turned it because it was tired when I got it. Weiand 7515 xcellerator intake. All Ford Mustangs | Model Specific Forums, GT-40P Heads - 5.0 Mustang & Super Fords Magazine. Come join the discussion about popular models such as the Mustang, Galaxie, Falcon, Fairlane, Torino, Shelby and many more! Install a set of GT-40P cylinder heads from a late 1990's Ford Explorer or a set of GT40 heads from an early 1990's Mustang 5.0L. Using the manufacturer recommended springs for your camshaft are a safe bet. I have to agree, the GT40P heads flow better than the GT40 iron heads. Can I run the new cam with the same roller hydraulic lifters or do I have to change the lifters too? K.S. this head fits years 95-01 explorer mountaineer mercury mountaineer . Always the weak area in the 289 and 302 is the tiny 5/16 inch connecting rod bolts and the miniscule intake and exhaust ports. could the gear of off the oil pump drive(i know they're DIS), for the explorer motor be used on his dizzy? Step 1. With the tuning finalized, the little cam made far more power than we expected, cranking out 328 lb-ft of torque at 4,200 and 294 hp at 5,400 rpm. As you might expect with more duration, the idle quality dropped significantly but was still able to make 11.5 inches of vacuum at 980 rpm. But the part about a cam replacement possibly being a labor intensive undertaking is correct. people can stop saying that adding aftermarket cam with stock heads is a waste of time. There are caveats to this plan, however. A bone stock 2bbl early 351w with stock replacement forged pistons (9.0 compression) and dyno headers made 211 Hp . He has worked as a tractor-trailer driver and mechanic, a rigger at a fire engine factory and as a race-car driver and builder. If you can get the mentioned GT-40 heads with studs for a good price, that would be good for you. For additional insurance, we also added a set of ARP head studs, which are stronger and offer better thread overlap than factory bolts, which helps prevent pulling threads out of a used block. This is not a criticism but instead consider it to be more of a heads-up. The spark plug issue is almost a non-issue. The heads that were used were also old C8 casting with 58cc chambers. As with Chevrolet's small-block engine, the aftermarket has had dozens of years to expand the range and reduce the cost of the parts they offer for this engine. However, when we dyno'd the car before installing the GT-40P heads, the fan was on the car. the engine is carburated of that makes a difference. This test went so well that we were eager to see what the slightly bigger cam would do. Hey Motorheadty,Like your comments,question for ya,I have a 92 convertible,just bought a 5.0 out of a 94 gt that was just freshened up top end,gt40p heads w/new springs etc for the new E303 cam,new FRP roller lifters,Crane 1.7 rockers,hardened push rods,double roller timing set,all put on a bottom end w/104000 miles,needless to say previous owner pulled said engine after 800 miles and now building a 351,I pulled engine down my machinest,putting forged internals in and bolting everything back together,I want to run about a 150 shot N2o,and iam going carb,wondering which intake would be best w/the 150 shot,heard that dual planes might not be the way to go? BONUS TEST-FOUR DIFFERENT 302 INTAKES.. What would be the best cam and springs to use for these heads in a 302 Windsor? There are a couple of reasons for this suggestion. However realistically, with the amount of money spent modifying the gt40p heads or even those older 289 & 351w heads, you could have even better performing aluminum heads. Calculated compression to 9.8:1. The newer camshaft is designed for use with a soft bronze distributor gear, not the hardened steel gear used for older camshafts. The kit offers adjustable power from 50 to 250 hp with a simple jet change. i'd love to use these heads,. I am working on a set of iron GT40s hoping it goes faster. Have fun, be safe, enjoy. AFR 165cc 58cc Heads. 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. Runs well. Most of them are aware of what changes need to be completed. Yea. Late-model ford GT40 and GT40P heads with 1.84-inch intake valves will also flow 185 cfm at 0.50 . The GTp heads are like GT 40's with smaller combustion chambers and the spark plugs are relocated for a more efficient burn. This needs to be removed and different exhaust valves, retainers, and valve springs added to turn this into a decent street head. There are literally a dozen or so camshaft companies that offer a mild hydraulic roller cam for a 5.0L Ford. ported GT-40p, ported cobra intake, 65mm BBK, e-cam with 1.7s, longtubes, off-road x-pipe with flowmasters dumped. Depending on the Headers you have you might be okay. Well assume it is a 5.0L with stock heads. Vehicle: 1972 2 door 302 maverick, 1986 5.0 stang gt convertible,66 mustang coupe, HEMI ram. The only failures Ive had were timing chains and a couple broken rods in a mid 80s 302 with 200,000 miles on it that got about 35 lbs of boost stuffed into it when a pop off valve I bought on ebay failed. There are too many variables to add to this regarding aftermarket stroker kits or components. All in all, the addition of GT-40P heads to any 5.0 Mustang is a worthwhile venture, especially if you're on a budget (aren't we all) or shooting for the Trophy Stock title. 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. The Fora platform includes forum software by XenForo. A COMP hydraulic roller cam we found works well with this combination. Yeah, except those. a) ain't early and b) aren't 289 heads. Small-block Fords and Mopars only use four head bolts per cylinder, so retaining proper head-gasket sealespecially with nitrousis a point that demands attention, so we ordered a set of Fel-Pro MLS head gaskets rather than a standard, composition gasket. GT40P heads, what kind of performance do they give? Im now thinking of adding a cam to match the carb. GT40s have 64cc chambers. Im a different animal. This engine will be good for your 65 Mustang. However, since Holten's car has an E303 cam, we didn't want the pistons and valves becoming too close, so we chose the 1.6 rockers. You'll have to plug the oil hole that is in the engine from the old oil dipstick. I'd get the gt40 setup, and put an s trim on it. The dyno recorded a peak horsepower reading of 489 hp, but the air/fuel ratio was slightly on the rich side at 11.5:1, so we increased the nitrous jet to a 61 and hit the button again. 02-11-2012, 07:16 PM #6 fiveoh 86lx These are some of the pictures I have showing the Explorer manifolds. Those heads were unported and had stock valve sizes! With the GT-40P heads you will need to back off the timing a couple degrees and bump up the fuel pressure. There is a better way. When I purchased my "brand new" set of GT40P's, I bought them from an Mustang specific machine shop that used to exist called Central Coast Mustang. #1:::Throw out all your Magazines that suggest what to do! Free shipping for many products! I guess I had it backwards, sorry about that, didn't mean to spread misinformation. I must agree with Jeff Smith. Ford GT40P 302 5.0L 4 Bar Cylinder Head Assembly Pair w/ 1/2" Head Bolt Hole. That's a good combo in my book. thats after 3 hours of idling/midrange hits to tune the idle and part throttle . Because of this, your tuneup will probably need to be modified. Commonly referred to as Explorer heads, GT-40P iron castings are found on current 5.0-equipped Explorers. I'll prob take a trip up there this weekend after scavenging the junkyards, thanks a million. The Fora platform includes forum software by XenForo. Consider having the head's intake ports matched to the intake manifold gasket. You'll also have to use your 289 timing chain cover since it has a hole for the oil dip stick and fuel pump. There are several actions that could trigger this block including submitting a certain word or phrase, a SQL command or malformed data. Joined . http://vb.foureyedpride.com/showthread.php?t=89153, http://www.facebook.com/groups/233213650060739/, 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