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True Hotrodder
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Yes sir.
 

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Not all Chevy manifolds use the rear coolant returns. Some don’t tap these at all, some pick up one side often as a heater source, others offer returns on both sides. This is variable from the factory as much as the aftermarket.

I only use those that have 4 corner returns as I think the old SBC benefits from this. The paired exhausts create a hot spot in the middle of the head, I modify all my build to bring most of the coolant return at this spot. The rear exhausts also run a bit too hot, I like to bring up a little more little coolant here as well. The fronts run the coolest as they are being fed stream that is just off the pump. These temperature differentials between exhaust seat temps and those of adjacent but cooler areas encourage the SBC’s famous casting cracks so I do things I think are reasonable approaches to reduce the thermal gradients between these very hot and just hot locations. To that end I like to use the thermal wash off the adjacent exhausts to level out the cylinder to cylinder combustion chamber temps and the exhaust seat temps to adjacent areas which includes spark plugs and intake valves which requires using both ends of the heads as returns.

I’m not above modifying the Edlebrock intake but I use more Professional Products intakes for this reasons I stated.
Bogie
 

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When the Holley Group took over Weiand they went the cheapo route and eliminated the rear water passages on SBF versions of the Stealth intake. SBF's being a thinner block casting benefit from having front and rear water passages to equalize cylinder cooling my Professional Products SBF intake has front and rear but it looks like they are going el cheapo as well the older ones are pretty much gone off the market.
 

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When the Holley Group took over Weiand they went the cheapo route and eliminated the rear water passages on SBF versions of the Stealth intake. SBF's being a thinner block casting benefit from having front and rear water passages to equalize cylinder cooling my Professional Products SBF intake has front and rear but it looks like they are going el cheapo as well the older ones are pretty much gone off the market.
You have to be careful with 4 corner return on the Ford. The SBF does not cool like the SBC largely because it doesn’t use adjacent exhausts in the middle of the head. The SBF brings coolant to the rear of the block then feeds the heads which flow the coolant forward to a return at the front. The idea being that cold coolant is introduced at the front of the block making those cylinders the coolest running with those at the rear the warmest. Then the coolant flow forward in the head this gives the rear cylinders the hottest cylinder but the coolest combustion chambers while the coolest cylinders in front receive the hottest combustion chambers. This is simply a scheme to balance out cylinder to cylinder operating temperatures and thus power. The problem on these engines if using 4 corner coolant return is that unless modification is made to reduce the back of the engine coolant transfer and increase it elsewhere too much coolant is shunted to the return at the front without doing any further work.

Most GM engines, the Chrysler A and B blocks and the Ford big and small Y blocks use the old Hispano Suiza valve and port layout which pairs up exhaust valves in the middle of the head. This creates a sizable heat concentration which demands a different approach to coolant transfer from the block to the head as compared to alternation of the in and out valve and port layouts. A big help in any engine is swapping the adjacent firing cylinders on one of the banks at the rear of the engine to moving that forward so that two cylinders immediately next to each other with the hottest coolant aren’t firing 90 degrees apart. While this is sold as making better power, it’s really a better distribution of temperatures which might or not actually make power mostly through better detonation/preignition supression.

As I said awhile back, I bring most of my SBC coolant up the middle to give priority to wetting those adjacent exhausts then return at the ends of the heads. Even FelPro started including instructions with their gasket sets for how to do this modification. For competition SBC’s it is a common practice to drill and tap the heads at this location and the coolant pump to deliver cooled coolant directly to this point. The SB2 engine was the end point for this paired exhaust arrangement, the power being developed as heat energy finally hit the limit of what could be done with crutching this area of heat concentration with more and more coolant.

Bogie
 

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You have to be careful with 4 corner return on the Ford. The SBF does not cool like the SBC largely because it doesn’t use adjacent exhausts in the middle of the head. The SBF brings coolant to the rear of the block then feeds the heads which flow the coolant forward to a return at the front. The idea being that cold coolant is introduced at the front of the block making those cylinders the coolest running with those at the rear the warmest. Then the coolant flow forward in the head this gives the rear cylinders the hottest cylinder but the coolest combustion chambers while the coolest cylinders in front receive the hottest combustion chambers. This is simply a scheme to balance out cylinder to cylinder operating temperatures and thus power. The problem on these engines if using 4 corner coolant return is that unless modification is made to reduce the back of the engine coolant transfer and increase it elsewhere too much coolant is shunted to the return at the front without doing any further work.

Most GM engines, the Chrysler A and B blocks and the Ford big and small Y blocks use the old Hispano Suiza valve and port layout which pairs up exhaust valves in the middle of the head. This creates a sizable heat concentration which demands a different approach to coolant transfer from the block to the head as compared to alternation of the in and out valve and port layouts. A big help in any engine is swapping the adjacent firing cylinders on one of the banks at the rear of the engine to moving that forward so that two cylinders immediately next to each other with the hottest coolant aren’t firing 90 degrees apart. While this is sold as making better power, it’s really a better distribution of temperatures which might or not actually make power mostly through better detonation/preignition supression.

As I said awhile back, I bring most of my SBC coolant up the middle to give priority to wetting those adjacent exhausts then return at the ends of the heads. Even FelPro started including instructions with their gasket sets for how to do this modification. For competition SBC’s it is a common practice to drill and tap the heads at this location and the coolant pump to deliver cooled coolant directly to this point. The SB2 engine was the end point for this paired exhaust arrangement, the power being developed as heat energy finally hit the limit of what could be done with crutching this area of heat concentration with more and more coolant.

Bogie
The idea of front and rear water passages on the SBF was brought up often on SBFtech.com which at one time was a very active site it looks like the moderators have departed :( and the manifolds of choice there were the ones mentioned above. Do you think there is a relation with the change in firing order made in later SBF's ?
 
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