Vetterman muffler weight

[Lars]

Yes, I know the obvious way to find out would be to call Vetterman exhaust and ask, but it's Saturday and I'm hoping to get an answer sooner

Specifically my question is, how much more does a pair of Vetterman mufflers weigh than straight pipes?

I'm finishing an RV-9A that has Vetterman mufflers on its IO-320. The CG worked out to be pretty far forward due to decisions made by the original builder. Enough that in order to keep the weight on the nosewheel under 325 pounds I can't fly it solo with full fuel without about 20 pounds in the baggage compartment- for that matter, even someone far more svelte and attractive than me would have the same problem. If the weight difference between straight pipes and mufflers is significant that could move the CG aft enough to mitigate some of the need for ballast.

For what it's worth, the aircraft is always within the published CG range for any loading condition; the issue has to do with the Van's Nose Gear Letter dated November 9, 2007 which shows a chart of gross weight versus nosewheel weight for various CG conditions. It is the limiting factor for loading on this airplane. Painting it will help since that moves the CG aft, but that's going to be up to the next owner.

I'm sure nosewheels are great, but I love my tailwheel RV-7

[JohnInReno]

An EarthX ETX680 will remove 10 lbs from the firewall. I have been using one since Feb 2016. Check out their website or threads here on VAF.

[Lars]

Originally Posted by JohnInReno

An EarthX ETX680 will remove 10 lbs from the firewall. I have been using one since Feb 2016. Check out their website or threads here on VAF.

Good point. That would help, a lot.

[Clint B]

Mufflers add about 2 lbs to the total weight of the exhaust vs straight pipes. Hope this helps. Clint

[Lars]

Originally Posted by Clint B

Mufflers add about 2 lbs to the total weight of the exhaust vs straight pipes. Hope this helps. Clint

Thank you Clint. Not enough to make me want to remove them in that case. I have them on my RV-7, the admittedly subjective feedback I've gotten from folks on the ground (my plane is quiet compared to what they expect) compels me to keep them if possible. The battery swap sounds like a better way to kill some weight for now.

[Robert Anglin]

Clint knows these weights and if 2 Lbs. is all you are looking at you may want to think about some small amount of lead installed in the tail. The Aero. guys do this to zero out their weight and some of them have small containers that they can pore shot into and then drain it back out after their matches. It does not take much back that far aft to get you where you want to be and you can keep most of that gross weight at the same time. Just some other idea for you. Yours, R.E.A. III #80888

[airguy]

The RV10 elevator balance weights are a convenient 2.5 pounds each in a single piece of lead - one or two of those bolted under the empennage fairing will move the CG considerably without adding too much total weight.

[Lars]

Originally Posted by airguy

The RV10 elevator balance weights are a convenient 2.5 pounds each in a single piece of lead - one or two of those bolted under the empennage fairing will move the CG considerably without adding too much total weight.

It turns out that 4 pounds at the 10th bulkhead would negate the need for baggage ballast but it messes with my OCD to add weight. Though I'm not ruling it out. The 2 pounds I could get back by losing the mufflers wouldn't be enough. The battery swap would though. Had I been involved with this build from the beginning I would have done some things differently.

It does surprise me in my searches involving w&b and various nosewheel concerns that little mention is made of Van's service letter with its charts. Surely it's standard practice to check this as part of a w&b check. I attached a copy of the chart to the w&b document in the airplane.

[JohnInReno]

Originally Posted by Lars

It does surprise me in my searches involving w&b and various nosewheel concerns that little mention is made of Van's service letter with its charts. Surely it's standard practice to check this as part of a w&b check. I attached a copy of the chart to the w&b document in the airplane.

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