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Today on eBay I ran across a Edelbrock 7501 Black Air Gap listed with a "Rear Cool Kit". The kit appears to be a sharp looking black braided hose, some NPT fittings that must fit the manifolds water ports and some other parts. Its my understanding that there is no way for coolant to circulate from the rear of one cylinder bank to the other rear bank. Does that kit allow that to happen via the hose and fittings?
I don't see that cooling kit fitting in the limited confines of a C3 engine compartment. Anybody know about the Rear Cooling Kit? Pretty slick set-up.
Ok, I see. Circulates coolant back to front. I figured, looking at those parts on eBay that the kit circulated from drivers side to passenger side across the rear.
Last edited by HeadsU.P.; Aug 25, 2018 at 07:44 PM.
Ok, I see. Circulates coolant back to front. I figured, looking at those parts on eBay that the kit circulated from drivers side to passenger side across the rear.
I cant say either way if it works....found this link. Some seem to think the lines should be very small otherwise all the coolant is bypassing the head.
I cant say either way if it works....found this link. Some seem to think the lines should be very small otherwise all the coolant is bypassing the head.
Today on eBay I ran across a Edelbrock 7501 Black Air Gap listed with a "Rear Cool Kit". The kit appears to be a sharp looking black braided hose, some NPT fittings that must fit the manifolds water ports and some other parts. Its my understanding that there is no way for coolant to circulate from the rear of one cylinder bank to the other rear bank. Does that kit allow that to happen via the hose and fittings?
I don't see that cooling kit fitting in the limited confines of a C3 engine compartment. Anybody know about the Rear Cooling Kit? Pretty slick set-up.
very slick and totally worthless. Hooking a cross pipe between the rear cylinders would have little or no flow and that is the hottest cylinders.
connection from the rear sides to the thermistat crossover is beneficial
gen 1 small blocks are very poorly designed as to uniform cooling
gen I I like the Lt1 in the 80s used a reverse flow water pump sending cold water from the radiator to the heads first and then down to the cylinder water jackets
the most trick intake I have ever seen was an 8 stack sprint car motor They eliminated the front cross over and thermistat return. They plumed the return from the rear head ports to the radiator
I have returns from each rear to my raised filler cap
Not sure that pic makes sense. There is a front crossover ttube hats really not needed as the T stat area underneath does the same thing?
I bet the owner of that Dart Intake is a plumber-by-trade. The only thing missing is a butt-crack.
Anyway, engineers said several decades ago that the SBC had poor water circulation.
And looking at that Dart proves once and for all that their engineers got drunk at the same bar as Edelbrocks engineers.
Could you guys have put the Vacuum port in a worse place than that? Ridiculous!
Another beneficial thing that can be done is run lines from each side of the waterpump to the block drains along with a Fel-Pro 1003 gasket. There is an added hole to help cool the center cylinders as well as an enlarged hole towards the top. This combined with the lines from the rear to the front on the intake will help our poor cooling engines out a lot. I was going to do this but got lazy. Next time.
I cant say either way if it works....found this link. Some seem to think the lines should be very small otherwise all the coolant is bypassing the head.
Pressure created by the pump? OK... pump to block to heads to intake to thermostat housing to radiator to pump.
Yes, from the front of the block, through the cylinder water jackets and up through the heads and only exit is through the front t-stat. So the front cylinders are cold compared to the back. Ideally, You would want to restrict or eliminate the front cross over to the T-stat and have all the return from the rear out of the heads to the radiator.
V2racing was showing an older racing idea of more flow from the center cylinders. Back in the old day's of when the 400 block came out they ran external lines from the rear on the sides of the block to the pump suction side of the water pump. Even though it was not going through a radiator it kept positive flow
We recommend installing a pair of –10 AN lines that connect the rear of the aluminum cylinder heads to the thermostat housing crossover in the front. This step will help offset the smaller water jackets. A pair of -10AN lines connecting the pressure side of the water pump with the area in the center of the cylinder head (just below the exhaust ports) will offset the lack of surface area due to the extra material
Personally, if I was running lines I'd do like the above quote. Go from the pressure side of the pump to the middle of each cylinder bank or to head in the exhaust valve area. Run return lines from each corner of the cylinder heads. You've got to get the coolant going into the middle and out the ends of each bank to more evenly cool the bank. An important part not mentioned is restricting the stock passages at the front of the block to force a decent flow through these lines.
Also remember that temperature measurements by themselves don't always give the whole story. Say you only put lines from the back of the intake to the thermostat. You will then get flow from the back head ports to the thermostat which is bypassing some of the head passages. So, you might see lower temperatures at the thermostat even though the center part of the head is running hotter because you reduced the coolant flow in the center part of the head.
Different Edelbrock Air Gap
