bigphil

My Feedback: (6)

Can someone please measure the inside diameter of a Magnum 1.80 4 stroke exhaust for me. I lost the back cone out of my muffler and a machinist friend made me a new one. I just guessed at the exhaust diameter and I think it's too big. I'm getting quite a difference in performance even though I've richened it up a good bit. So I'm thinking I have insufficient pressure to the tank.

Thanks in advance for your help!

goirish

Are you talking about the very end of the exhaust, where it steps down from the barrel of the muffler

bigphil

My Feedback: (6)

Yes the very back end of the muffler. There is a tapered back cone, which necks down to where the exhaust exits the muffler. I need the inside diameter of the exit.

bigphil

My Feedback: (6)

The inside of the little tube where I drew the arrow

goirish

Just got my loaded ready to go flying in the morning. How about 8mm. Measured twice, 1st. 7.94, second 8mm.

bigphil

My Feedback: (6)

Thank you!

bigphil

My Feedback: (6)

Thanks again Irish, my machinst buddy made a plug with the correct size oriface and it's back to its old self now. Out flying today and it ran great!