I have been told that i can take a 302 block and put 351 windsor heads on it. Will this work? If so what will it do as far as power gains? Is there anything else i would have to change?

 

youd probably want to look for a set of 69 windsor or gt40 heads if you actually wany to gain performance from stock heads.

 

early 351w, or gt40(off a 302) heads are best, but i've been told late model carb heads are good with a little port work. that's what im doing. using heads off an 87 351W. If the project gets done sometime this century I'll let you know how it turns out.

 

Nothing. Zip. Nada. The heads are exactly the same.. except for the larger bolt holes in the 351 version. If you want gains you'll have to port a set or go aftermarket.

 

The early 351W heads had larger valves 1.84 1.54 and they had larger intake ports.. C9OE or D0OE heads are the good ones chambers where 60cc....but wait someone might tell you they had 62 or 64 ...but you get the idea.

 

351W has 1/2" head bolts vs 7/16" head bolts on the 302. One option is to have 302 block holes enlarged to 1/2" or use bushings in the 351W heads. As for the late model 351 heads I have to agree with Scotty, Conanski, and HemiEater, no gain.

Prior to 1970 or so and EPA regs these heads would be more desirable. The after- market has lot of offerings that are 50 state legal aswell as off-road only. The gt40 and gt40p heads offer significant improvement over other stock offerings. Hope this helps. I picked up a set of edelbrock performers off ebay for a reasonable price. These are 50 state legal. I won't know for a while the improvement. Motor is currently on the engine stand. Hope this helps

 

why is it when someone ask something about iron heads aluminum heads always gets thrown into the post.........

He ashed about 351W heads................I think we all know aftermarket heads are available....

 

My reason is that life is full of choices. Some of my choices are economic. If good iron heads, such as gt 40s or gt40ps or pre 70s like on my 69 bronco are available and don't need any machine shop service I wouldn't hesitate to put em on in a minute.

When I weigh local machine shop costs for valve and seat grind, guides, true surfaces etc.. etc.. those costs plus the purchase price of the heads weigh in. Some times the aftermarket is a choice cuz out of the box and money spent is so close.

Just my opinion.

 

yup your right but he asked about iron 351W heads.....might just as will get a crate motor too because by the time he takes the heads off and bla bla bla.....

 

So basically its not really worth the time to put windsor heads on if they arent going to give me any more power.

 

'69-'77 351W heads will give you a little power boost over some other stock heads. After '77, 351W heads are the same as 302 heads, which aren't worth poo.

scottie2hottie, If those heads are off an '87 truck, they will be E7TE's, which again are the same as HO 302 heads of the same era. If they are off a police car, they will be E5AE's and pretty much worthless as far as performance goes.

 

the ones i have are e7's.(actually taking e5's off in favor of them so I hope theyre a little better) theyre going on a 302.

 

E5 and E7 are so close it's not worth talking about. Either will outperform the other with some mild port work. I have both in my shop, and side by side you get them confused unless you can see the casting numbers.

 

Don't know if this helps but if you have E7TE head and they are in good shape I'd get a cam that favors the exhaust. Or put 1.7:1 rockers on the exhaust side and the stock 1.6:1 rockers on the intake side. I had some decent results w/just changeing the rockers as listed above.

As for heads here are some flow numbers I have collected from the internet and other sources. I only list the Trick Flows from the after market cuz thats all I have. You can see an improvement w/Gt40s and GT40Ps over the E7...s The GT40p heads might give you a headache when it comes to exhaust manifold/header fitment and your particular application. As a rule of thumb I look at the flow numbers at .300" lift first. It's just an area that says alot.
INTAKE EXHAUST
.100" .200" .300" .400" .500" .100" .200" .300" .400" .500"
E7TE 59 114 144 156 156 42 78 105 115 116
GT40 54 107 157 183 192 47 94 119 128 128
GT40P 61 128 169 195 196 52 90 123 135 139
TFS/TW 63 141 205 233 251 53 107 144 171 187
cert.

 

Sorry the spread of numbers didn't turn out as I wanted. Intake numbers are left of the exhaust numbers. The numbers on the far right should be below the .500" column. The numbers starting w/59 should be below .100" : I Need to work on the puter skills.