Where to start with disks in a custom V-rod application?

[mwdhand]

I'm using a single 4" Supertrapp megaphone muffler on a set of 2:1 headers from another exhaust manufacturer on a 1250 V-Rod. How many disks should I be using on the 4" to get similar flow to the 5" system that's made for the V-Rod? I have a PC3 map for the 5" 2:1 I was going to use a basis for this.

List closed and open endcap if possible.


Thanks

[hugger]

I'm using a single 4" Supertrapp megaphone muffler on a set of 2:1 headers from another exhaust manufacturer on a 1250 V-Rod. How many disks should I be using on the 4" to get similar flow to the 5" system that's made for the V-Rod? I have a PC3 map for the 5" 2:1 I was going to use a basis for this.

List closed and open endcap if possible.

Thanks

With the 5" on a stock set up we suggest 8 discs with the closed endcap, with the 4" discs you might want to try 12-14 discs with the closed endcap.

When using the open endcap you will take off approximately 8-10 discs. So if you are running 14 discs with closed, run 4 discs with open endcap. This will maintain the same performance as with the closed but will give you more sound.

Remember that with SuperTrapps your elevation and humidity will affect the tuning and you may need to run more or less. Be sure to use high temperature anti seize on the disc screws everytime you remove them and re insert.

[mwdhand]

Thanks. I ended up with an adjustable Trapp cap with two oval ports on the end, so I'm running 12 disks and usually keeping the cap ports closed, only opening them when I want to shatter nearby windows. The system I'm running is working very well, sound is adjustable from loud high performance, to insane dragster and the power is definately there with ports opened or closed. Feels like more low end grunt with them closed.