head gasket question

[slighty_sykotic]

Hi,

Some of you know, im building up a 4agte for my trueno, and have almost come to the assembly stage.

Now, i've got myself a new head gasket, and i'm a bit confused... It seems to be blocking one of the holes (both in the head and the block).

http://pocketpower.co.nz/tsimages/hg.jpg
MOD edit - dont post massive pictures

But, then I look at a TRD one, and its the same thing, so i guess its meant to be like that? But why?



--Sykotic

[slighty_sykotic]

The right hand hole...

[Malcolm]

AFAIK they normally use the headgasket to control cooling to parts of the head, to get uniform temp distribution and prevent warping. They do this by making changes to the holes in the headgasket to increase or reduce coolant flow into the head.

[fangsport]

AFAIK they normally use the headgasket to control cooling to parts of the head, to get uniform temp distribution and prevent warping. They do this by making changes to the holes in the headgasket to increase or reduce coolant flow into the head.

but why??surely the thermostat can control localised heating??

the 4K gasket is similar.

if it was my engine, i'd open the bastard up, better to have temperature controlled coolant flowing in the pocket, than a superheated pocket of air

[Malcolm]

there will probably be stationary coolant in there, it just wont flow/flow much (the water gallery in the head will be connected to other parts too).

The thermostat controls temperature of the coolant throughout the engine, but it doesn't control specific temperatures in the head. Remember that you will have more heat on the exhaust side of the head, and the inner two cylinders generally would need more cooling than the outer two.