Topic: Heat riser......... necessary?
in Forum: C3 Fuel, Emission Control, and Exhaust Systems
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Houston, TX - USA
Joined: 2/7/2008
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Vette(s): 1970 454 4 speed A/C power everything else
I know it performs a function, but It seems it also clogs exhaust flow....................
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It allows the engine to get to operating temp quicker, as it helps re-routes hot exhaust thru the bottom of the intake manifold. If the valve is functioning properly, it will open completely when hot...usually about 5 minutes or so. If it is stuck shut, it will hamper performance, for sure.
So...is it necessary? Not really...big blocks seem to warm up pretty well on their own! Since you're here in Texas, you prolly won't see enough really cold weather to make it mandatory to have.
So...is it necessary? Not really...big blocks seem to warm up pretty well on their own! Since you're here in Texas, you prolly won't see enough really cold weather to make it mandatory to have.
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Most folks tend to remove them.
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Mounds View, MN - USA
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Vette(s): 70 LT1 coupe, 69 350 HP coupe, 69 390HP 427 coupe, 71 LS5 convert, 85 coupe, 93 coupe
There is a simple heat riser eliminator. It is just a heat riser casting that was never drilled for the extra parts. They are about $30.00. You do need to use this piece or your exhaust pipes won't fit.
Larry
Larry
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Houston, TX - USA
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Posts: 93
Vette(s): 1970 454 4 speed A/C power everything else
Thanks, I have the old one..........I could "gut it" an reuse it.
Former Member
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Mounds View, MN - USA
Joined: 5/24/2007
Posts: 1031
Vette(s): 70 LT1 coupe, 69 350 HP coupe, 69 390HP 427 coupe, 71 LS5 convert, 85 coupe, 93 coupe
If you gut the old one, be sure to weld up the holes where the shaft went through.
Larry
Larry
in Forum: C3 Fuel, Emission Control, and Exhaust Systems
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