Cabin heat from front or aft baffle?

I?m building a 7 with IO-360 angle valve. Are there any pros/cons to routing the cabin heat starting from front or aft baffle? I have a vetterman exhaust with a dual muff from pipes for cylinders 1 and 3. If I take air from the front, are there pros/cons to routing the scat tube through, or around the pipes under the cylinders.

Thanks.

My setup using a single heat muff has no tube from the baffles and works just fine down to about 20F, which is more than adequate here in the south.

Mine comes off the rear baffle with no issue.

If you are looking to maximize your heat, cover just the heat muff with exhaust wrap, available at most auto parts stores. That will keep the heat in muff and help bake you out of your cabin.

Maybe not exactly what you're looking for...

The builder of my bird put the air intake in the front baffle just ahead of #1 cylinder. There was a bit of spaghetti-looking SCAT tubing also installed getting it from the intake, to the heat exchanger, to the firewall...

Vetterman exhaust installed.

FWIW, my heater never really seemed that effective (as auto heat is) and heat output really went downhill when you pulled the throttle back for descent. I tried stuffing it with steel wool...didn't try wrapping it as I'd heard that can hide problems during inspections.

Since I too live in a more moderate climate (South) and felt the heat system has its issues (efficacy/CO/Maintenance) I decided to go another route and pulled the heat exchanger off the exhaust pipe. Completely deleted it.

I pulled the old SCAT tubing off from the previous install and used new SCEET tubing instead. (More water resistant) Ran it from the front baffle intake back to the firewall (pretty much like the original installer had done with the heat exchanger present) and securing it where needed to keep it from moving around.

It now makes another nifty fresh air inlet pushing cool outside air into the cabin at our feet and offsetting at least some of the heat gain off of the firewall (which is more of a problem in my climate than trying to stay warm.)

For cold conditions, I bought a couple of cigarette-lighter-plug seat heaters from Amazon:

https://www.amazon.com/Wagan-IN9438...40502770&sr=8-4&keywords=auto+seat+heater+pad

and supplement those with battery-powered heated jackets from an outdoor store:

https://www.thewarmingstore.com/mobile-warming-mens-rain-gear-jacket.html

I still have the old heat exchanger and SCAT tubing, so it's an easy project if I want to go back to as it was before, but with one cold season under my belt with my new setup and no complaints of being cold from the Wife, I'm going to keep what I have for now...

Rob

N941WR said:

Mine comes off the rear baffle with no issue.

If you are looking to maximize your heat, cover just the heat muff with exhaust wrap, available at most auto parts stores. That will keep the heat in muff and help bake you out of your cabin.

Click to expand...

I did this as well, standard rear baffle inlet. I took a couple of layers of 1/16" thick fiberfrax insulation, wrapped it with heavy oven foil (sealed it) and wrapped my heat muff can. A template was made from cardboard first. It is held in place with safety wire. Works well down below zero, but it has enhancing heat transfer studs welded to the exhaust pipe.

Raymo said:

My setup using a single heat muff has no tube from the baffles and works just fine down to about 20F, which is more than adequate here in the south.

Click to expand...

Ray, I like your idea, but I have one question. When you are not using cabin heat there will be no airflow through the muff. Have you seen any overheating problems with the muff or scat?

Ron B.