Polished air system components

[SimonR]

Do you reckon it'd make a difference in an S-Series engined car to polish the inside of the inlet manifold and plenum so that they'd not cause turbulence in the air passing through them?

I've had a variety of responses from 'no difference at all' to 'as much as 5 bhp' depending on whom I've asked.

What do you lot think?

[Mat_C]

IMHO polishing does sweet FA. It might make 0.1% difference or something.

[G Force]

Hi there. polishing inlet manifolds, plenumn chambers & inlet ports is the wrong thing to do. They should be left with a shot blasted finish, polishing causes droplets of fuel to condense on the walls of the manifold etc. resulting in poor atomisation. Polishing of combustion chambers piston crowns, exhaust ports & manifolds is recomended.

Cheers gary

[E_T_V]

Couldn't have put it better myself. Air turbulence can be good or bad it just depends where it is!

[SimonR]

Thanks for that info - most interesting. In that case I'll leave them as the are! That's freed up a couple of evenings, which is nice. I think I'll spend them working out the order that I'm going to dismantle the various bits of the car :)