heat riser
Pro
Joined: Jan 2008
Posts: 616
Likes: 1
From: Huntersville NC
Race Director
Joined: Apr 2005
Posts: 11,265
Likes: 2,131
From: Bowling Green, Kentucky
If you live in a southern climate, it would probably be a good idea. If you live in Vermont or Maine, I would leave as is.
You can remove the butterfly and shaft and weld up the ends, or buy a fuel injected car exhaust spacer that fits in place of the heat riser. Paragon (and others) sell them.
I have done this on many of my cars when living in south Texas and Louisiana. Then used an electric choke (like you) or a manual choke.
If you maintain the heat riser correctly, leaving it in is not a big power loss or engine cooling/fuel issue. Especially in most parts of the country.
Larry
You can remove the butterfly and shaft and weld up the ends, or buy a fuel injected car exhaust spacer that fits in place of the heat riser. Paragon (and others) sell them.
I have done this on many of my cars when living in south Texas and Louisiana. Then used an electric choke (like you) or a manual choke.
If you maintain the heat riser correctly, leaving it in is not a big power loss or engine cooling/fuel issue. Especially in most parts of the country.
Larry
Team Owner
Joined: Oct 2000
Posts: 38,897
Likes: 1,926
From: Washington Michigan
You have to have either the heat riser valve or a fuelie spacer in that joint, or the exhaust pipe joint won't seal; the R.H. manifold outlet surface is flat, and the top of the heat riser or spacer is also flat, and uses a gasket with a steel ring to seal. The bottom of the heat riser or spacer is chamfered, to accept the angled sealing surface on the "donut" that seals to the exhaust pipe inlet. 
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,874
From: Greenville, Indiana
You have to have either the heat riser valve or a fuelie spacer in that joint, or the exhaust pipe joint won't seal; the R.H. manifold outlet surface is flat, and the top of the heat riser or spacer is also flat, and uses a gasket with a steel ring to seal. The bottom of the heat riser or spacer is chamfered, to accept the angled sealing surface on the "donut" that seals to the exhaust pipe inlet.
And even if you did find some way to pull the pipe up and make it seal, it's now too short to the engine and will probably ground out on the frame somewhere and rattle.
This has been an issue before here on this forum, believe it or not!
