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VetteLT193
06-06-2008, 08:46 PM
On closed cooling with stock manifolds where does the coolant return?

I have lines that go into the manifolds (at the bottom of each manifold) and additional lines that go into the risers. The lines that go into the manifold are part of the closed cooling system. the lines that go into the risers are the raw water dump.

I'm trying to figure out where the return from each manifold is because I don't see it...

gcarter
06-06-2008, 09:15 PM
On closed cooling with stock manifolds where does the coolant return?
I have lines that go into the manifolds (at the bottom of each manifold) and additional lines that go into the risers. The lines that go into the manifold are part of the closed cooling system. the lines that go into the risers are the raw water dump.
I'm trying to figure out where the return from each manifold is because I don't see it...
From the TOP of the manifold, the coolant returns to the coolant side of the HE.
The raw side of the HE discharge goes to the risers.
If your risers are stock, there are closed gaskets in the joints.

VetteLT193
06-06-2008, 09:33 PM
From the TOP of the manifold, the coolant returns to the coolant side of the HE.
The raw side of the HE discharge goes to the risers.


So, are the square/hex bolts at the top of the manifolds / base of the riser equivalent to the feed that comes out of a high end exhaust? basically the feed that is connected by a hose?

I'm thinking that I can pull the hex/square bolt (the one below the fitting in the manifold in the pic), put in a fitting, run a hose from the manifold to the riser and be ok. Is that correct? this would make it like aftermarket exhaust if I have the proper understanding of the system.

I would essentially bypass the built in water ports in the manifold and riser and use and external fitting.


BTW, I'm still trying to figure out the hydraulic stuff and am confused as ever...

gcarter
06-06-2008, 09:41 PM
You have it!

VetteLT193
06-06-2008, 09:50 PM
You have it!

holy crap I figured something out this week :bonk:

Thanks George. You are the Donzi Encyclopedia as always:wink:

MOP
06-07-2008, 12:39 PM
Here is a helpful diagram that should be posted in a tech section if we still had one.

cutwater
06-07-2008, 02:07 PM
Really helpful diagram George. I never realized that the coolant flow in the exhaust manifolds essentially stops as well (other than the trickle from the pressure relief path) when the thermostat closes. Is there ever a case where the exhaust manifolds get really hot, but the coolant temperature on the blocked side of the t-stat is much lower? Shouldn't there be a bypass that allows FULL coolant flow to the exh. manifolds when the t-stat is closed?

gcarter
06-07-2008, 03:21 PM
Big Griz uses a large T-stat controlled (on the HE) system on his Criterion. It's designed for boosted engines and allows for full circulation in the engine w/the HE mounted T-stat closed...in other words, the T-stat controls coolant flow in the HE, not in the engine. It's also kind of pricey.
I'd like to use one my self and may if I can find a deal.

gcarter
06-07-2008, 03:23 PM
But to answer your question, it doesn't really matter.....it allows everything to warm up quickly which is particularly important if your engine is EFI.

MOP
06-07-2008, 04:57 PM
The manifolds run almost identical to the block to the block maybe 3-5 degrees difference measuring at the outlet fitting by the riser.

MOP
06-07-2008, 05:01 PM
George I need to ask Randy about the Tstat in the exchanger and the reasoning, I have seen block mounted, duck bills in the bottom hose and remote did not seem to make any difference. Still did the same job as far as I could see.

Phil

BigGrizzly
06-08-2008, 09:25 AM
Phil, the reason is that this is a full flow system. This means that the water is not restricted by the T-stat. What happens id the heat exchanger mixes the cool coolant with the hot creating even temperature of the coolant without restricting the flow. This eliminates water pump cavitation. This is the type of colling system used on the new Cobra's and Corvettes. BTW it reduces the HP drain of the circ pump. The system is really good just a little expensive. It yses 496 tupe T-stats.

VetteLT193
06-09-2008, 06:59 AM
Here is a helpful diagram that should be posted in a tech section if we still had one.

Great diagram! THANKS!!