ideal exhaust diameter or a 1.6 VTR?????

[air121005]

As the title suggest, i'd like to know what the ideal diameter exhaust pipe is for a VTR to optimise its torque / bhp?

[CampDavid]

2 1/4 IIRC. 2.5 is too big (BTB)

[jonesyFX]

yea more than 2.5 will just add mor sound wont it? tht about it ?

[CampDavid]

pretty much. You start loosing performance as the exhaust won't pull the gasses out of the cyclinder efficently. I'm not big on this so I'll let someone with more expertise fill this in, but 2 1/4 is the ideal bore for a VTR

[Barry123]

there some random shitty equation i know which relates internal pressure (gases exiting engine), external pressure (atmospheric), nozzle diameter (exhaust), enthalpy, entropy and a few bits of shite...

I'll dig it out when i can be assed, but too thin a nozzle creates a restriction where as too wide has something to do with shock wave expansion and creates inefficient flow as a result rah rah.

[yorkie]

ad your on form again mate!!!

[air121005]

cheers fella's!!!!!!! i know i don't post on here often but i use the search feature constantly and this website is a great source of information!