70/71/72 402

1964SuperStocker

Well Known Member
Supporting Member 3
Tooth,
Using the 781’s on the first block, put 225/188 valves in, it’s the spec you and Don J came up with. It will have a 700R4 behind it
I have a set of 236 and a set of 360 for the second block. Going to build a torquer motor. I’m thinking the 236 are the better of the 2 because of the better exhaust opening.it will have a TH400 behind it
https://www.youtube.com/results?search_query=bbc+peanut+port+heads
Nothing wrong with peanut port heads. They can make some power, just not drag racing monsters like 291's but I found these videos helpful in finding combinations that would be worth building.
 
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425/409ER

Well Known Member
1409236086-88oval OPEN454 Truck
33678173-85oval OPEN454, 118cc chamber, 256/114cc ports
34623675-87oval OPEN454, 120cc chamber, 225/116cc ports
33678173-85oval OPEN454, 118cc chamber, 256/114cc ports
Tim here is a comparison and I cannot find any numbers on the 360 heads either. The 781 is used on a lot of 496 motors. The intake runners are 31cc bigger than the 236. They also have a 113 combustion chamber. Since they are peanut ports they will automatically give you more low-end torque and more throttle response from idol. Not much good above 5000 RPM with any cam. If you’re going to put a small lumpish lump choppy idol The 236 will work fine. Not sure about the 360 due to the lack of numbers. I’m sure they’re fairly similar.

Number one, GM did not use 781's on any 496's they build which were only built in the mid-2000's. As for the little peanut port heads 236's or 360's my 236's were in the high 11's and the 360 which I think are a far superior head to all the others, the car was in the 11.20@117mph and the 360's I did will pull 6500 any day of the week with only an 8:1 compression engine. Even after some chamber work my 360's cc'ed @116. People always snear at those little runner heads until they get beat by a set. Look up Vortecpro online, his little peanut pot BBC makes very close to 600hp and is streetable.
 

Tim

Well Known Member
Supporting Member 4
Number one, GM did not use 781's on any 496's they build which were only built in the mid-2000's. As for the little peanut port heads 236's or 360's my 236's were in the high 11's and the 360 which I think are a far superior head to all the others, the car was in the 11.20@117mph and the 360's I did will pull 6500 any day of the week with only an 8:1 compression engine. Even after some chamber work my 360's cc'ed @116. People always snear at those little runner heads until they get beat by a set. Look up Vortecpro online, his little peanut pot BBC makes very close to 600hp and is streetable.
Clift notes of what I’m doing;

Both engine blocks I have are 5445 markIV blocks. One is 4 bolt and one is 2 bolt. The 4 bolt came with the oil cooler holes in the filter boss the 2 bolt came with an adapter for the same cooler. Both out of motor homes and neither came with 781. The 4 bolt had 360 heads and the 2 bolt 236. The 781’s I have to go on the 4 bolt I don’t know what they came off but I had them redone with 225/188 valves, roller rockers, roller cam and I mild ported them myself. Bottom is 25cc dome pistons and 30 overbore. Eddy 7161 intake and a Holley 850 carb on top.this I have ready to put together.
The second(2 bolt) I’ll do relatively stock except 25cc dome pistons and use the 236 heads( they are in better shape than the 360) I’ll use a flat tappet cam, stock rockers, (so I can use stock covers) and I’m thinking a Holley sniper for the top with an eddy intake.
both motors are not for racing or above 6500 so I used the stock cranks to keep the costs down.
 

Tooth

Well Known Member
Supporting Member 3
Number one, GM did not use 781's on any 496's they build which were only built in the mid-2000's. As for the little peanut port heads 236's or 360's my 236's were in the high 11's and the 360 which I think are a far superior head to all the others, the car was in the 11.20@117mph and the 360's I did will pull 6500 any day of the week with only an 8:1 compression engine. Even after some chamber work my 360's cc'ed @116. People always snear at those little runner heads until they get beat by a set. Look up Vortecpro online, his little peanut pot BBC makes very close to 600hp and is streetable.
The 496 is a stroked ..060 454, I may have worded it wrong. A lot of people who build 496 motors use a 781 head. What I should’ve said was a lot of people use the 781 on a 496 stroker motor!
 
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