Exhaush Temp Difference
Thread Starter
Racer
Joined: May 2003
Posts: 406
Likes: 5
From: Miami FL
Exhaush Temp Difference
With the engine idling I took the temperature from each header collector just out of the flange, and I'm puzzled by the differences. The temp on the odd side of the engine were all about 200f +/- 15, but on the other side, cylinder 2 and 8 were about 90degres cooler, #4 and 6 were the same as the other side around 200f. Any ideas, is this something to worry about and investigate further. BTW, the engine is a 427BB aluminum heads, solid cam(a pain to adjust).
Drifting
Joined: Jan 2001
Posts: 1,358
Likes: 26
From: Florida
I do not think you should worry about it. You are at idle, the flow of the coolent through the engine will produce some differences because it is cooler just leaving the radiator and warmer as it enters. Running at a stand still your motor is not seeing any benifit of air flow. The job of the cooling system is to keep the coolant at a constant temperature but engines have hot spots where the metal is thicker, thinner, seeing different rates of air and coolant flow. If you are worried your cyls may be running hot check your plugs if they are all nice and tan and appear just about the same forgettaboutit! On the other hand if after a spirited drive, 7 are nice and tan and one is solid white or solid black then you may want to take a closer look.
Just my 2cents.
Just my 2cents.
Drifting
Joined: Mar 2005
Posts: 1,300
Likes: 0
From: Iowa
Exhaust temperature is a function of load and air/fuel mixture. In very general terms, for a given load, a leaner mixture is hotter.
You didn't mention your intake manifold type, but many dual plane manifolds route the mixture from one primary venturi to 4 of the cyli8nders, not all on the same side, and the other venturi to the others.
If one of the idle mixture screws is a little lean, it will lean out 4 cylinders, but the farther two will be warmer than the near two due to the longer runners and fuel dropping out of the air stream.
You didn't mention your intake manifold type, but many dual plane manifolds route the mixture from one primary venturi to 4 of the cyli8nders, not all on the same side, and the other venturi to the others.
If one of the idle mixture screws is a little lean, it will lean out 4 cylinders, but the farther two will be warmer than the near two due to the longer runners and fuel dropping out of the air stream.
