Small block heads

P

Pops1532

Junior Member
I'm starting to accumulate parts for an upcoming project.....68 XL. I want to build a 302 or 351W with good performance, but want to keep it streetable. I'd like to build a 351 but budget may dictate a 302 since I already have a few laying around. What heads would work the best? I've got a buddy that has some 289 hi-po heads that I might be able to get. Would they flow enough for a healthy 302 or 351? I also have a pair of 351HO (the HO was a 351W with flat tops,and a 4barrel)heads from an '84 truck. How do they compare to the early performance heads?
Should I just look for something else?
Thanks in advance.
Pops
 
the hi po heads on a 351 might give a little too much compression, after about 1974 the 351 and 302 heads were the same valve sizes and all
the hi po heads on a 302 make a great combo, thats what I use and sometimes install bigger valve if there is enough room to do so, and the 351 heads on a 289 lowers the compression too much, I tried it and the darn thing woudn't pull the hat off my head, the 289 heads are around 58 cc's
you would be better of checking combustion chamber size and figuring the ratio before spending money on heads, I have a book on small block ford engines it has a wealth of info.
Hope this helps.
D.Estes
 
also I use the 1969-70 351 heads on my 351's, they will have a casting number c9 or d-o they are of the best compression for the 351's
D.Estes
 
I figured the 2 sets of '68 or the '89 302 heads I have weren't going to be what I need. Still kind of curious about the '84 351HO heads. I'll probably see if I can talk my buddy into parting with the hi-po heads.
What's the book with the info on SBF?
Thanks!
Pops
 
Biggest problem with the SB heads were the exhaust ports. Way too small and restrictive. Opening them up by doing a simple port matching with a dremel will vastly improve flow and up performance and it's easy to do at home.
 
The factory iron heads used on Explorers a couple years are suposed to be the good ones. They have two lines cast in on the ends of the heads. I also like the Edelbrock aluminum heads for a street motor. They show very good dyno numbers when used as a whole kit from Edelbrock.
 
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Pops1532 said:
I figured the 2 sets of '68 or the '89 302 heads I have weren't going to be what I need. Still kind of curious about the '84 351HO heads. I'll probably see if I can talk my buddy into parting with the hi-po heads.
What's the book with the info on SBF?
Thanks!
Pops
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Here's the book: http://www.mre-books.com/interchange/index.html to your left click on Heads in blue to preview it shows how to ID the Hi-Po's you really won't gain much as far as exhaust breathing goes but you will gain some compression you may want to go this route: http://www.kmjent.com/cart/product.php?productid=4520&cat=17&page=1 by the time you pay a machine shop to upgrade the stockers you could have these and gain real serious horsepower.
 
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If this car is a 68 Galaxie XL, its a heavy car. The 302, no matter what heads, cam, compression or carburation, it is not going to make the torque that will make you happy. Bite the bullet and use a 351, that extra 1/2" stroke will be much more to your liking. As mentioned the C9 and D0 heads will be the cheapest deal for a 351, just open up the exhaust ports. The 84 HO heads have smaller valves and bigger combustion chambers and still need to have the exhaust ports opened up
 
craig said:
If this car is a 68 Galaxie XL, its a heavy car. The 302, no matter what heads, cam, compression or carburation, it is not going to make the torque that will make you happy. Bite the bullet and use a 351, that extra 1/2" stroke will be much more to your liking. As mentioned the C9 and D0 heads will be the cheapest deal for a 351, just open up the exhaust ports. The 84 HO heads have smaller valves and bigger combustion chambers and still need to have the exhaust ports opened up
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I agree with Craig. The 351 w is more bang for the bucks and wont cost any more than the 302 to over haul. On heads the 351w for stock are ok but there are better ones available for under 1000.00 if you got the bucks or pick us a set of GT 40 heads as there are a lot out there for sale as well as other hotrod aluminum heads..
 
Fordestes said:
also I use the 1969-70 351 heads on my 351's, they will have a casting number c9 or d-o they are of the best compression for the 351's
D.Estes
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Ditto. I used 69 351W heads on my old 302 Fairlane and it was a good improvement. You need special washer headed bolts or hardened washers to use them on the 289/302 block. It was 30 years ago but I think the pushrods were changed also.
 
Don't the 351s use bigger head bolts?
I have also heard, but never used, the Exploder heds, GT40-P heads. They are supposed to be fairly decent. The problem I always seem to see with the old heads is the cost. If they need rebuilt you might as well buy a new set of aftermarket heads for about the same money. You can easily sink over $500-$600 into a set of early heads.
 
Well 289 HiPo heads are nice BUT by the time to get a valve job done and exhaust seats , you are going to have $600+ in them ! I would put that money to a better set of heads ! You can get real Cobra GT40 heads for the money you will put into the HiPo heads and have a much better flowing , bigger valve heads . Now if you can get the HiPo heads real cheap , then I would sell them for someone restoring a Mustang that had a 289 HiPo in it . Otherwise they are just 289 heads with better flow basically . I have a set of 289 heads I am using on a 1984 --302 for the compression . The heads were heavily rework with 1,90 intakes and ported , drilled with screw in studs and had Crane roller rocker and guide plate . I saw them on C/L one day for $450 and bought them ! Those had about $1000 in parts and labor in them .
On todays market you can buy some very nice alum for $1200 so why waist the money rebuilding a set of HiPo heads that won't give you anything close to what that same money can buy you today . I look at the money invested to the gain I will get and that will not get you thee HP & torque gain that a better set of heads will for the same money . Don't get me wrong , the HiPo are nice head but ONLY if someone else rebuilt them with new exhaust seats !
Just remember ANY heads that are earlier than 1974 you will have to put exhaust seats in and have a triple angle valve job done and exhaust seats aren't cheap ! You will be looking at $400 for just the exhaust seats . Then add the rest of the work . Kinda get the idea ?
Just my opinion !

Jim
 
willowbilly3 said:
Don't the 351s use bigger head bolts?
I have also heard, but never used, the Exploder heds, GT40-P heads. They are supposed to be fairly decent. The problem I always seem to see with the old heads is the cost. If they need rebuilt you might as well buy a new set of aftermarket heads for about the same money. You can easily sink over $500-$600 into a set of early heads.
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Yes the 351w bolt holes are larger and you have to buy sleeves to use them on a 289/302 block .
The GT40-P heads are OK BUT you will hate yourself when you have to put headers on them . Shorty headers will not work because they hit the back spark plug ! Have to use long tube headers . Not worth the trouble unless they have just been redone and are $250 !
You can build a Clevor small block . Take 351c heads and bolt them to the 289/302 and make sure you have the 351c intake too because nothing else will work ! Those were the Clevor engines back in my racing days back in the mid 1970's .
Still the best heads for a SB back then were the 1970 -- 351w 4 bbl heads with the large valves !

Jim
 
Jim, to use the cleveland heads on a 289-302 engine you can't use the 351 cleveland intake manifold, too wide for the short deck. Use a boss 302 intake or better yet, Edelbrock builds one to match the 2V intake ports
 
I was thinking back a long time ago and thought we used that intake . Back then so many parts were swaped around and "made to fit" buy having a machinist shave things down that I thought that was done that way . Nice that Edelbrock make an intake to safe the day !

Jim
 
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