47-55.1 Exhaust manifold temp

[nvrdone]

Here's a fun one.
I just put a new 4 row radiator in MY Ad with a 327. Just for curiosity I started checking temps with my temp gun.
At the top outlet, the temp shows 177 deg. At the thermostat housing it shows 188.
I have cast iron rams horn exhaust manifolds. At the "V" in the middle of the right manifold it shows 217 deg. On the left it shows 422 deg. Does that sound right or should I be checking something? Possible coolant flow problem ?
Thanks

[leegreen]

do you have a stuck exhaust butterfly on one side that is forcing all the exhaust through the intake manifold heat riser to the other side?

[mr48chev]

Originally Posted by leegreen

do you have a stuck exhaust butterfly on one side that is forcing all the exhaust through the intake manifold heat riser to the other side?

Good point there if the truck still has the heat riser valve in the exhaust.

You should be able to tell real quick by checking the heat of the pipe down the pipes a ways. If the left side is a lot warmer than the right side that is the issue if the right side is still hotter the right side may be running lean but that doesn't fly with most manifolds that feed two cylinders on each side.

188 on the thermostat housing or just above it should mean that you have a 180 Thermostat and life is good temp wise.

[nvrdone]

no t'stat in it yet and no heat riser in the exhaust. left side is the hottest. Both sides are individual pipes from the manifold to the muffler. I will test temp next time I go for a drive.

[mr48chev]

Is there a big temp difference between the manifold runners on each cylinder?

[nvrdone]

dont know - I will check the runner temps hopefully this weekend

[nvrdone]

OK, Rob. Here's some stats. These were taken with a temp gun with 85 deg outside temps after a run into Yakima.
There is no thermostat installed right now.
Carb is an Edelbrock 4 bbl square bore. The manifold is an Edelbrock aluminum, not a high rise or air gap.
Left bank cylinder # intake exhaust right bank cylinder # intake exhaust
1 170 370 2 185 460
3 760 4 763
5 165 715 6 170 575
7 495 8 290
ON the intake manifold left front runner 207 left rear 105
ON the right front runner 208 right rear 108
At the "V" where the center exhaust ports come together left side is 760 right is 405
At the exhaust pipe where they enter the mufflers, left is 176 right is 166
What concerns me is that there is such a wide variation in temps.
The intake runner temps seem to be close to each other front & back.
The concern is the wide variation in temps at the exhaust manifolds
Any ideas from anyone would be appreciated.

[mr48chev]

I'd have to go out and dig my performer intake out of the shed and figure out if he hot exhaust is coming from intake runners feeding off the same side of the carb or same plane of the intake.

[nvrdone]

Im wondering if I have a coolant flow problem. With the old radiator I never had this problem but I didnt flush the system when I installed the new radiator. Wonder if there is some kind of blockage. Just a thought

[leegreen]

remind us why the rad was changed?

If you had a coolant blockage.....what are the temps on the cylinder heads / sides of the block?

I think mr48 is on an interesting idea: what is relationship between hot side and the the configuration of the intake runners / carburetor barrels? One side might be running lean (hot) or rich (cold); jet adjustment, mismatch jet sizes, a blockage inside carb.

have you pressure tested cooling system? Or checked to see if it holds pressure as it cools after a run.
Any bubbles coming up in tank when it is running? (headgasket?)
Valves over adjusted on one side of engine might make one side run at a different temperature - but I think it would run badly if it was that badly setup

[nvrdone]

rad was replaced because it started leaking after 30 + years. Don't know what the temps on the heads or block are. No bubbles in cooling system. Valves haven't been adjusted in years. May be time to do that. I'm thinking back flush the block, adjust the carb & adjust the valves.
I have an adapter that I can hook a garden hose to the water pump outlet hose and back flush the block that way.