Have my original 54,000 mile 1974 Ford 302 engine I saved for years now ready to redo it with better items for my 1955 Ford F-100 What CAM to use and what type heads to use-- DO NOT need HP-- it is a STD bore needs to be Honed and stored apart correct all these years, CLEAN and NO rust all complete but NO heads--
I used 1969 351 Windsor heads on a 302 years ago. You get bigger valves stock. But you need either washers or the special Ford made head bolts because the holes in the 351 are bigger. Thats a cheap way to go.
Isn’t there a later model head from an explorer that is a good upgrade? I can’t recall the name of them though.
I have the GT-40 heads (three bar) on my 302. The later explorer GT-40P heads flow a bit better, but have slightly different (edit) * Spark plug * locations that could cause some header to spark plug fitment issues (so I've been told).
351w 4 bbl cam wakes a 302 right up, idles good, real responsive. It is the cam Ford used in the H.O. 302's before they went to roller cams. Be mindful it changes the firing order to 351 !
The 69/70 351 heads have larger ports than the 302 head along with valves , the Explorer head can be a problem fitting headers or manifolds. I haven’t looked at prices lately but you should be able to find a set of new aftermarket heads for a grand , you can easily spend that much or more on a used set at a machine shop bringing them up to snuff.
If I didn’t have a set of heads, I’d just buy a set of the cheap aluminum heads. You would probably end up cheaper than buying an old set of heads and having the reworked. The aluminum heads will run cooler and have better flow so you can get by with lower octane gas.
Best way to go 351 C , 2v heads with special intake for the swap . If not that way , stock closed chamber heads are fine for a driver . GT40P is not the way to go for a driver , they require special designed headers , just not worth the effort to drive around . Stock cam with , early timing gears late ones retard cam timing . 37* full timing advance and it will last many of fun miles .
Around here you can buy a set of used 302 heads for $50 for stock 74 type heads. Chances are they need completely gone through, springs, guides, seats, surfaced, etc.... if they are really rebuildable at all. Like BamaMav said, it cost about the same to buy a set of aluminum heads brand new. The issue I ran into was like you I was trying to build a solid reliable 302 that made good power and torque AND was not planning to exceed 5,000 RPM. Opinions are like belly ****ons, everybody has one. When trying to research heads one brand is great and another brand is **** according to this engine builder or that builder but then they all point to a dyno graph that one makes 416 HP and the other only makes 394 hp at 6500 RPM. I don't care, a good solid 275 HP would be good with me and you can do that with stock iron heads. The cost of redoing (machining) the stock heads along with all the parts is the issue. Flip a coin my friend, GT40P heads seem like a good choice but as been said will still need to be redone and have some header fitment issues. Be careful of heads with 2.02 inch intake valves because they can require different pistons or fly cutting your pistons. The cam will dictate the RPM range of your engine.
If it was mine, I'd look at any of the smaller chamber heads. I think more compression might be better that just better ports for slow speed operation. The 74 is in the smog area and the compression ratios back then were pretty low.
Yep, the early '70s to early '90s SBF heads are not performance pieces. Finding a set of '65-70 heads would offer more compression, but by the time you do the probably-needed guides, seats and valves you'll have most of the price of a set of cheaper aftermarket heads. The various GT40 heads are good, but the same math may apply. The one caveat with the cheaper aftermarket heads is the supplied valve springs can be suspect, figure on replacing those. Personally, I'd hunt down a 351W core. Find a '95/96 version and have a factory roller cam. Uses pretty much all the same parts with the same prices, but that extra 1/2" stroke really wakes up the torque curve. Add in a $400 or less 3.85" stroker crank that uses stock 351 rods and 302 pistons for 392" (and don't rev it to the moon) and you'll have a low-RPM torque monster... that most guys will mistake for a 302...
If it were mine I’d rebuild most any 302 oem head…if it’s reasonably cheap. Once the cost starts getting to the 75% cost then just buy a set of aluminum heads. He mentions just a stock rebuild, no performance stuff. A rebuild on a stock set of 302 heads would be around $750-1000.
Flo-Tek 180cc.....58cc combustion chamber volume, 1.94/1.54" valve combination, 180cc intake port volume Small chambers to keep compression ratio from going in the toilet like 1970's smog heads will, and so that flat top pistons work well(even 69-70 351W and the newer GT40P heads are at 64cc), nice 1.94" intake valve diameter is far bigger than stock choked port Ford 302 heads, but not so big to need piston mods to clear them, plus they are nice aluminum, have better modern chamber shape and far better adjustable rocker system. Just over $900/pr......you won't be far from that figure just rebuilding stock junk heads. Small Block Ford 180cc/58cc | FloTek - Evansville, IN (flotekheads.com) Trick Flow also has some nice 302 sized heads, just a bit more $$$
Do 'they' still make Windsor jr. iron heads ?! That's what I wanted back a few years ago when I built my 5.0 engine. They were a bit cheaper than Al. heads and no worries if the engine ran hot by accident. I had them milled down to get 9.5 CR and put them right on the engine. Sure thy are heavier than Al. but...Al. needs to have 10:1 CR to MAKE UP for their running cooler than iron. I needed guide plates for the pushrods because I used adjustable roller rockers (which upon further research do NOT make any more HP than stock rocker......just a bragging point) Street performance does NOT need 202 intake valves either ! (that's just shivel-laz I reckon!) When ***embling the engine rotate the pistons on the rods for a better angle to the crank pin. The pistons are offset on SBF engines. (free HP) ARP rod bolts and have the stock rods resized. As good as HP rods without the expense....max RPM around 7000 'occasionally'! You COULD....use 289 rods with a custom piston and make it a boss 302 without the huge port heads. That's more money for small gains for a street engine. Isky type camshaft with 108* LSA but somewhat mild duration gives super performance on the street. Take pictures and post'em fer us !!!! 6sally6
Yes you can dig up some old cast iron heads, have them all redone and have quite a bit of money in them. From my perspective, why not put modern aluminum heads on it - you'll not spend much more money and you'll pickup some very useable street horsepower. Example: 185cc SBF Enforcer Cylinder Head (airflowresearch.com)
These heads have stock sized valves and are setup for a flat tappet cam but the cost is attractive. https://www.summitracing.com/parts/flk-203-505f
Not a stock Ford valve size....standard 302 is 1.78" intake valve, some of the performance stuff and 351W got 1.84". 1.94" is a stock small block Chevy size, but very commonly added to Ford small block heads as a budget upgrade in the old days. That's for a single head, ***embled. Pair is $930 or so.
From post #6, the GT40 (not GT40P) heads have the same spark plug location and angle as the regular 302s. They also have hardened exhaust seats. You might be able to get a decent set that can simply be bolted on and run for a reasonable price. They also have pedestal mounted rocker arms that are fine for mild performance use. If you go this route, you'll need pushrods from an engine with a flat tappet cam and pedestal style rocker arms. The pedestal style rocker arms started in about 1978 or 79, and the roller cams started in 1985 in some cars, a few years later in other cars and trucks. To be sure to get the right pushrods if you order a set, specify something like a 1980 pickup with a 302.
The plug location is the difference in GT40P heads . Tough to get at plugs with std 302 headers . Look inside the exhaust port of OEM 302 head . See the bump inside , use care and remove the bump , and you will breathe much easier .
Thanks @Beanscoot & @deathrowdave for the clarification... I knew there were some header - sparkplug issues, but had mistakenly thought it was exhaust port location when it was spark plug location. Thanks!
For what it's worth.....The HiPO exhaust manifold work great (so I've been told) on these heads. Since it'sa street engine this could be an option. 'They' DO make headers for these heads that work. (prolly better than the run-of-the-mill headers that CLAIM to fit SBF!) 6sally6
Shortys; I don't know if still available. Just a set I had hanging on the wall from project never started.
I was fortunate when I got my engine, it came with the GT-40 heads and a set of JBA shorty headers and was a roller cam block. Not a bad deal when I got the entire truck it was in for a couple of hundred bucks.
Since you are not looking for a performance build just use some that don't have the holes for the smog plumbing.
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