Coolant crossover tube at back of engine...needed?
Coolant crossover tube at back of engine...needed? I installed an LS6 intake on my engine. I quickly figured out that the stock coolant lines under the manifold would not squeeze in there. I fabbed up a cross over for the front, but I simply capped the two rears.
The question is, is this safe? Could that have caused the heat that may have destroyed my motor? (seems like it let go around #7) or is it normal to just block off the back ones?
I am installing an LQ4 as a replacement for my boomed motor and am considering making a crossover for the rear as well. What are yall running?
The question is, is this safe? Could that have caused the heat that may have destroyed my motor? (seems like it let go around #7) or is it normal to just block off the back ones?
I am installing an LQ4 as a replacement for my boomed motor and am considering making a crossover for the rear as well. What are yall running?
Mine has the caps on the rear of the heads. If you go find a way in your situation to form a crossover and route it back up to the radiator, that would be ideal, but not necessary. You are fine leaving them capped.
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I believe they are called steam tubes and were designed to cool cylinder #7 because of heat and detonation problems. I believe i pulled them off the back of my lq9. I would guess they are there for a good reason, but maybe GM found another way around cooling it with out them. I know the early gen lll's had an x setup but I think was changed with the introduction of the ls6 manifold in 2001. (became standard on all gen lll car engines). Dont quote me on that.
Good luck
Good luck
I know its overkill for a mostly street driven car, but I installed two Front Crossover Tubes to my car when I added my LS6 Intake. One on the front and one at the rear.
I then attached some 1/4" Rubber Fuel Line to the Rear and plumbed it and the Front Crossover to a "T" Fitting and then to the Radiator.
It really wasn't that tough and it insures each cylinder is being properly cooled.
But, again, its probably overkill since GM installed the Rear Block-offs from the factory on 2001 and up LSx equipped vehicles.
I then attached some 1/4" Rubber Fuel Line to the Rear and plumbed it and the Front Crossover to a "T" Fitting and then to the Radiator.
It really wasn't that tough and it insures each cylinder is being properly cooled.
But, again, its probably overkill since GM installed the Rear Block-offs from the factory on 2001 and up LSx equipped vehicles.
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Has anybody ever definatively proven or disproven the idea that having the crossover blocked off heats up the cylinders, #7 in particular? I wouldn't be too keen on grinding or chiseling on the bottom of a new intake.
Mine's already taken care of with block off plates, but I'm just curious
Mine's already taken care of with block off plates, but I'm just curious
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From: rosemount,mn/windsor locks,ct
I did the same thing and it has worked great. I figured if there were lines running to the rear of the heads originally,then why would I want to block them off with the plugs. Just my .02.
I know its overkill for a mostly street driven car, but I installed two Front Crossover Tubes to my car when I added my LS6 Intake. One on the front and one at the rear.
I then attached some 1/4" Rubber Fuel Line to the Rear and plumbed it and the Front Crossover to a "T" Fitting and then to the Radiator.
It really wasn't that tough and it insures each cylinder is being properly cooled.
But, again, its probably overkill since GM installed the Rear Block-offs from the factory on 2001 and up LSx equipped vehicles.
I then attached some 1/4" Rubber Fuel Line to the Rear and plumbed it and the Front Crossover to a "T" Fitting and then to the Radiator.
It really wasn't that tough and it insures each cylinder is being properly cooled.
But, again, its probably overkill since GM installed the Rear Block-offs from the factory on 2001 and up LSx equipped vehicles.
Has anybody ever definatively proven or disproven the idea that having the crossover blocked off heats up the cylinders, #7 in particular? I wouldn't be too keen on grinding or chiseling on the bottom of a new intake.
Mine's already taken care of with block off plates, but I'm just curious
Mine's already taken care of with block off plates, but I'm just curious
rovided the coolant system is properly evacuated***. The coolant that surrounds cylinder 7 & 8 has ONLY been through the block, by the time is makes it back up towards the front of the engine, it has passed a mixture of the block and multiple combustion chambers, and the combustion chambers are where the majority of heat comes from. The front of the engine has better ***EDIT: external*** air cooling though. From the gauges, it shows to run about 3-5*F cooler on cylinder 7 versus cylinder 1. Last edited by 1SLwLS1; Sep 24, 2010 at 09:24 AM.
The water temperature is not changed a readable amount when the engines have a problem. The vapor vent tubes are made to clear air out of the upper corners of the heads, if the air is present it insulates the combustion chambers on the rear cylinders and causes localized heating of the rear cylinders. This can aggravate the higher power engines if they are running hard with this air pocket present, normally resulting in detonation on one of the rear cylinders. If you use a stock waterpump/coolant and stock type power level it should be ok.
Kurt
Kurt
Has anybody ever definatively proven or disproven the idea that having the crossover blocked off heats up the cylinders, #7 in particular? I wouldn't be too keen on grinding or chiseling on the bottom of a new intake.
Mine's already taken care of with block off plates, but I'm just curious
Mine's already taken care of with block off plates, but I'm just curious
The tube that connects the front to the back and goes over the valley cover was elminated for Fbodies in 2001 and in stock form its not an issue.
You can grind on the intake, it wont hurt it. People do it to clear that tube. OR cut off and JB weld the ends. OR just get a 01+ set of lines, and then again just cap them off all together. It's a personal choice and do what you feel is right.
