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Discussion Starter · #1 ·
Have a 91 302 roller 0.30 with e303 cam. What CC size and intake/exhaust should I be looking for when purchasing a set of heads.
Also what rockers and rods to purchase.
 

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What are you looking for? Aluminum, Cast, Stock?

Need a little more info. As for the rods, I guessing you mean push rods; That will be dependent somewhat on your heads.
 

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Discussion Starter · #3 ·
Cast Iron and I plan on dual plane intake, 600 Holley and shorty headers hooked to a t5 and installed in a 68 coupe.
 

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I'd go with 58cc or less and no bigger than a 19.4" intake valve. If you want cast iron, what about the Roush/World windsorJr heads? Scorpion brand roller rockers go for about $140 on ebay and the quality seems impressive to me, from the sets I've seen at swap meets.
 

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Discussion Starter · #5 ·
I thought about the World Jr heads, I'm on a very tight budget and would like to get around 300hp. Can I get this with Gt40, Gt40p's
 

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Daf said:
I thought about the World Jr heads, I'm on a very tight budget and would like to get around 300hp. Can I get this with Gt40, Gt40p's
Yep, I'd take a set of GT40s and get 'em shaved and CC'ed to 55cc, and get the intake faces angle-milled so you can run an unmodified intake, and go for it. 300hp pretty easy in an SBF IMO.
 

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RHS 180's in cast iron are not only affordable, but flow great. They actually outflow AFR 205s up until .400. They do have 2.02 intake valves, so you'd have to rent the Isky flycut tool (no big deal.) Going with a GT-40 iron will give you a baby power increase, but not worth the hassle in my opinion. Windsor Jr's, as stated, are also another good option with a 1.94 intake valve. I've seen used sets on corral.net for around $500. Good luck.
 

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Your shortblock is the same as the 340HP GT40 crate motor from FRPP. That engine uses aluminum turbo-swirl heads as part of it's hp components. Those heads are worth between 20-30 hp over iron GT40 heads, and up to 40 HP over stock heads if you believe the specs advertised by Ford. Both iron and alum versions of the head have 64cc chambers (same as oem heads) for ~9:1 compression. So, assuming everything else in the engine is fresh and your head choice maintains at least 9:1 compression you should be pretty close to your HP goal. Rather than spend the money to buy iron heads that may need freshening anyway I think I would install 351W size valves (1.84"I, 1.54"E) with a 3 angle valve job and mill the deck surface to bump up compression a little more. This should keep the cost under $500 by reusing your present heads and still close the HP gap between stock heads the alum head used for the 340 HP crate motor. Of course, the more you spend on the heads the more power you will make. Modern aftermarket port design has made huge improvements over factory Ford heads, and they do it at very economical prices that make reworking iron heads not very cost effective. You can save maybe $200-$300 from the cost of aluminum heads by keeping iron heads with simple performance improvements (valve size, 3 angle grind, mild port/bowl work, etc) but the amount of HP to be gained by these mods is small compared what a good aluminum head can make right out of the box. You can just bolt on the stock '91 heads and with the cam you have you'll be close to your goal (I'd est about 275hp) and that might be good enough for you, but if you want to start swapping heads or working on the stock heads to boost HP the best HP per $ available is simply bite the bullet and spend the price for aluminum heads.
 

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I would personally say no to either of those.. First ones are E5's (And though it says highly modified, they are not desireable heads).. ANd I've never heard of the second.. Which would make me stay away...
 

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I agree. The "High Swirl" heads were an oem casting used for only 1 year ('86). With everything that goes into bringing a new part into production it should say something that Ford abandoned these castings after just 1 year. I've always heard to avoid the '86 Ford swirl heads, and I'm amazed anyone would put the time and money into modifying them to try to sell them. I think for the price you could find GT40 heads similarly prepped, which would be a much better choice.

As for the 2nd link, I've never heard of them either and can't find any info about them on the net so they are definitely a gamble.
 
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