15 replies to this topic

[Turbo Phil]

Without wishing to offend anyone.........

RC 40 is just a name - adds £20 to the cost! Simple straight through Cooper S silencer and some exhaust tube is all you really need.

RC40 is a specific and well proven design, it's not just a name.

I would get the larger bore - for a 1275. But no doubt others will say 1.75" !

1.75" is the optimum size for large bore normally aspirated A series engines. Any larger and the gas velocity starts to drop below acceptable speeds.

At last somebody who knows what they're talking about. SolarB is one of the only sensible replys in this whole thread.
On a really cooking big bore NA motor you may need a 2" system, but for you're application the 1.75" RC40 will be ideal. You want the medium bore LCB manifold to.

Edited by Turbo Phil, 13 July 2009 - 12:02 PM.