Buy the lifters for peace of mind now and hopefully for the duration. Our recommendation would be, rather than change the camshaft, you might want to look into adding a set of long-tube headers and a dual exhaust if the engine is not already so equipped. SB Ford, GT40 .575" Lift Max Output II Drop in Valve Spring Kit, Hyd Roller, 140 Lb Seat. The fix: basic power upgrades for a sluggish 302 Ford 302W / 5.0L History & Specifications - The Ranger Station The spark plug issue is almost a non-issue. Come join the discussion about popular models such as the Mustang, Galaxie, Falcon, Fairlane, Torino, Shelby and many more! I'll save the effort and lighten my front end by 50# with aluminum. With. the engine is carburated of that makes a difference. Weiand 7515 xcellerator intake. The newer camshaft is designed for use with a soft bronze distributor gear, not the hardened steel gear used for older camshafts. Install a set of 1.7:1 roller-tipped rocker arms on the heads. An aggressive cam will wake it up a bit. 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. For a better experience, please enable JavaScript in your browser before proceeding. Speedmaster PCE281.2046 Small Block Ford Aluminum Cylinder Heads 62cc We turned to Rare Auto Design in Orlando for dyno tests to find out how much horsepower we gained. There's not a lot of reson to use 351 heads later than '75 since they essentially identical to 302 heads except for head bolt holes. hole size 302 is 7/16 and 351 is 1/2 He'd be the best source. You will have to get special headers to fit these heads since the spark plugs are angled differently than normal 5.0 heads. We started with a 120,000-mile 5.0L out of a Ford Explorer, removed the EFI and DIS, and pocket ported the stock GT40P iron heads with stock valve sizes. After graduating from Iowa State University with a journalism degree in 1978, he combined his two passions: cars and writing. They suffered from poor aftermarket support up until about 15 years ago when it really came on strong. 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. And have discovered something that I dont think anyone else knows. When combined with modern power-makers, such as nitrous, the 302 is more than capable of producing 400+ horsepower for little more than the cost of a stock engine rebuild. Have fun, be safe, enjoy. I've got gt40p heads for it I'll be running, and can't afford better . I wouldnt recommend reusing lifters though. 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. 97% Positive Feedback . GT40P Heads how much hp from them. - StangNet Be careful, I was once bitten by one of those reptile engine builders. Ford Factory 5.0 Performance Cylinder Heads. This combination should be good for about 400 horsepower and as much as 500 if you opt to use the stronger aftermarket pistons. 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 you purchase through links on our site, we may earn an affiliate commission, which supports our community. GT-40P Heads - 5.0 Mustang & Super Fords Magazine - MotorTrend Just got through porting one of my gt40p heads today. JavaScript is disabled. Smith began writing for Car Craft magazine in 1979 and became editor in 1984. Many years ago, a friend bought a used 2001 Mercury Mountaineer 5.0L that was equipped with a set of really decent GT40P style iron heads. The GTp heads are like GT 40's with smaller combustion chambers and the spark plugs are relocated for a more efficient burn. I'd much rather be able to drive it at 8 or 9/10s of what it can handle. This test went so well that we were eager to see what the slightly bigger cam would do. 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. are you twisted331 also? This website is using a security service to protect itself from online attacks. Location: Re: Stock Ford 351W 4bbl dyno numbers. We also added an Edelbrock Performer RPM dual-plane intake and a set of 158-inch headers with no mufflers. You will have to address the 50 oz balance of the 5.0 engine by getting a 50 oz flywheel. Beyond the engine's amazingly good appearance, Moore had a couple of good reasons for choosing this engine. For real performance, stock E7TE heads leave a lot to be desired. You didnt mention what camshaft you would be choosing or exactly which 5.0L Ford Windsor engine you are working with. Stock 93-95 Cobra shortblock (stock cobra cam), GT40X heads, 1.7 rockers, Edelbrock Performer RPM intake, Holley 650, and longtube headers. Do you guys have part numbers for the spring kits? 1979 Indy 500 Pace Car. These are a great head but do need some machining mods to make they really work well. Since 2003, Jeff has held various positions at Car Craft (including editor), has written books on small block Chevy performance, and even cultivated an impressive collection of 1965 and 1966 Chevelles. SBF engines are modified constantly. This is the main reason why these engines are not modified as much as the small block Chevy. 402 HP NA from a HI PO 289 isnt that mysterious of a feat to accomplish with todays SBF Aftermarket parts availability. The heads that were used were also old C8 casting with 58cc chambers. We took the heads to Mike Slover of Slover's Porting Service in Sun Valley, California, to do this work, plus some basic pocket-porting to improve flowespecially on the exhaust side. Holten tells us removing the fan is worth two-tenths in itself, which tells us the fan soaks up roughly 20 hp. 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. In 1987, he assumed the role of editor for Hot Rod magazine before returning to his first love of writing technical stories. Come join the discussion about restoration, modifications, NOS parts, troubleshooting, VIN codes, and more! Advanced: Daily Deals; Help & Contact; Sell; My eBay Expand My . Runs well. Someone does make the Tri-Y's headers for the early Mustangs using the "P" heads. I got a set of AFR heads , night and day. 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. Consider having the head's intake ports matched to the intake manifold gasket. Ford GT40P 302 5.0L 4 Bar Cylinder Head Assembly Pair w/ 1/2" Head Bolt Hole. Both swaps made more sense when parts were readily available at the bone yard for cheap. THANKS VERY MUCH! Well assume it is a 5.0L with stock heads. The specs are a conservative 212/218 degrees of duration at 0.050-inch tappet lift but offer a really nice 0.512-inch valve lift for both the intake and exhaust. A forum community dedicated to Ford Mustang owners and enthusiasts. We guarantee plenty of burnout action when you add GT-40P heads to your 5.0 Mustang. I am very happy too. 331/347 stroker w/gt40p's, waste?Hp?cost involved? - Maverick I have a 66 mustang with its original untouched 289 with over 140 k on it that Ive been running a blow thru turbo making 14 lbs of boost on for the last 5 years and its never given me a problem. The GT40 heads have thermactor holes built in to connect to the EGR/smog equipment whereas the GT40P heads use an external EGR connective system. Generally expect with a good cam, intake, roller rockers and a good ignition system to see around 300-350 max rear wheel horsepower, depending on what type of dyno you use. 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? I'm also have the regular GT40 heads on my current build. Some ideas never go out of style. 289 or 351 heads on a 302 advantage? | The H.A.M.B. Thanks. I love my setup and it is very strong engine. 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. 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. I'm using the Trick Flow stage 1 cam with 1.7 roller rockers. Also, you'll need to get a steel distributor gear to replace the iron gear that is currently on your distributor. Holley 670 street avenger carb. Can I run the new cam with the same roller hydraulic lifters or do I have to change the lifters too? I just read about this build on the corral.net. The GT40P cylinder heads had a small combustion chamber ranging from 58-61cc while the GT40 heads had a 63-66cc combustion chamber. 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. . The Fora platform includes forum software by XenForo. So . They fill that spot between power and budget. With the P-heads requiring pedestal-mount rockers, we also called up Crane Cams for a set of 1.6 pedestal-mount roller rockers. A solid 300-325 hp should be plenty and that's with good drivability and reliability as well. I view the GT40P heads similar to Granada brakes. Nudge us with emails, and we'll make it happen. Stock Ford 351W 4bbl dyno numbers - Don Terrill's Speed-Talk Compare. anyone have experience with GT40P heads on a 92 351W I guess I had it backwards, sorry about that, didn't mean to spread misinformation. Purchase any used aftermarket manifold for the 302 that is designed to function in the 3,500 to 6,500 power band. You might even say its like flogging a dead horse without any animals actually being injured during my moments of sarcasm. 02-11-2012, 07:16 PM #6 fiveoh 86lx Also, the spark plug angle makes it a pain. Took me 7 hours to do one head.but they cleaned up real nice.