Performance exhaust manifold

[lepa]

Hey!
Is there any performance exhaust on the market for my vts 16.16v 2002 moddle? Does it make any difference?

Other mods: dynamic airbox with k&n filter. Cat removal.

[MartinObviously]

Having tested this on a dyno.

No.

I'm making 138hp with the standard cast manifold, with catalytic converter and exhaust.

I had a 4-2-1 branch manifold from a popular company, made the same power (actually made 0.5hp less peak but that could have been a difference in the dyno) with or without cat.

This is how my engine has been for 10 years, it's been on 4 different dynos and made the same power each time.

The last 3 power runs were on the same dyno, as I need a new power certificate for competing every year.