Heater muffs.....1 or 2

[Bsquared]

I am half way through phase 1 and I opened the pilot side heater vent for the first time (based in So Cal). It felt like a 2000 watt heat gun pointed directly on my feet! I installed the 2 muffs and plenum that came with my Vetterman exhaust. Do I need both and will I regret it later if I remove 1? Removing the muff on cyl #1 would also solve a scat tube/lower cowl rubbing issue I have been fighting.

[Bart]

I have the same exhaust equipment - originally installed only one then went back to two because I couldn't keep the scat clear of obstacles.

[Bsquared]

Bart
Any chance you can PM me a picture of your muff installation? Besides it being too warm, I am having an Issue with the scat tube that connects the exhaust of the muff on Cyl #1 to the intake of the one on Cyl #3 rubbing on the lower cowl. I have not found a combination of orientations that works.

[Bart]

Let me see if I have a couple. I'm in phase one now and just recowled it.

[Toobuilder]

Remove muffs, scat tubes and valves; replace with a length of wire and a power jack to plug your heated vest and insoles into. I'm just up the road from you and it works fine for me and my wife.

[Bsquared]

Originally Posted by Toobuilder

Remove muffs, scat tubes and valves; replace with a length of wire and a power jack to plug your heated vest and insoles into. I'm just up the road from you and it works fine for me and my wife.

I will have to see what my DAR thinks about that.... his hangar is right around the corner from you

[rvbuilder2002]

Originally Posted by Bsquared

Bart
Any chance you can PM me a picture of your muff installation? Besides it being too warm, I am having an Issue with the scat tube that connects the exhaust of the muff on Cyl #1 to the intake of the one on Cyl #3 rubbing on the lower cowl. I have not found a combination of orientations that works.

I don’t understand this comment because the SCAT tube that couples the outlet of the front muff to the inlet of the aft muff is only supposed to be about 2 inches long.
The ports on the muffs are meant to be positioned so they are aligned with each other, with the SCAT bridging the gap between them.

[Bsquared]

Scott
It may be because I am using a vetterman exhaust and the muffs Clint provided but the outlet of the forward muff is mis-aligned with the rear muff by about 15 deg in 2 plaines. I have to do a “slinky” arrangement to connect them and this results in the rubbing on the lower cowl. I don’t have any pictures to send until I remove the cowl for the next inspection.

[rvbuilder2002]

Originally Posted by Bsquared

Scott
It may be because I am using a vetterman exhaust

I missed that in your first post but that explains it.

[KeithB]

I have a Vetterman exhaust with 2 muffs, but I also have a Superior cold air induction sump, so potentially different. I plumbed my air differently than Vans instructions because of these differences, but I’m happy with the result and do not have cowl interference, though some clearances are close.

Conceptually, from the intake on the ramp, I went through the fuel injection air intake tubes to the back of the sump to a T split, sending intake air to each muff located on separate final exhaust pipes (output of 2-to-1), then each muff’s output goes to the separate heater vents.

Van’s installation has muffs in series using heat from 2 of 4 cylinders splitting output air - my installation uses muffs in parallel using heat from 4 of 4 cylinders splitting input air.