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Engine basics => Engine set up tips => Topic started by: Ron Varnas on March 29, 2009, 04:35:41 AM

Title: Correct Cyl. Head cooling & cowl designs ???
Post by: Ron Varnas on March 29, 2009, 04:35:41 AM
Hi all,

I'd like some input into the "correct" method for cooling our engines, namely SHOULD
the cylinder head of the motor should protrude "thru" the cowl & not like in some
designs either semi flush or even enclosed.

to my thinking the 'whole' section of the head should 'outside' the cowl base / bottom
not just half of it or some of the cooling fins exposed.
I know some motors run too 'cool' but I'm talking in general cooling terms preferably
ST 46.
Title: Re: Correct Cyl. Head cooling & cowl designs ???
Post by: Brett Buck on March 29, 2009, 04:13:30 PM
Hi all,

I'd like some input into the "correct" method for cooling our engines, namely SHOULD
the cylinder head of the motor should protrude "thru" the cowl & not like in some
designs either semi flush or even enclosed.

to my thinking the 'whole' section of the head should 'outside' the cowl base / bottom
not just half of it or some of the cooling fins exposed.
I know some motors run too 'cool' but I'm talking in general cooling terms preferably
ST 46.

    It's my opinion that a good fully-enclosed cowl cools the engine better than just hanging it out in the breeze. You can use the inside shape of the cowl to force air around very close to the engine. With current engines, however, I think that cooling the pipe is a much bigger issue than cooling the engine, so I am intentionally enclosing the pipe and allowing some of the air to bypass the engine.

    Brett
Title: Re: Correct Cyl. Head cooling & cowl designs ???
Post by: Ron Varnas on March 29, 2009, 08:34:11 PM
Hi Brett,

Good info on the cooling front, in theory it's like the old
automotive 'ram - air'

while on the cooling topic, is math that the air outlet holes
should be 2 ~ 2 1/2 times the air inlet hole...??
Title: Re: Correct Cyl. Head cooling & cowl designs ???
Post by: John Miller on March 30, 2009, 06:54:05 PM
Just to illustrate the point being made about 2 1/2 to 3 to 1 ratio, outlet to intake sizes, let me relate my experience with my Torino at the recent VSC.

I kept having overheating problems until I actually closed up the inlet to 1/3 the size. Overheating problem gone.