rv8

[ew_topcat]

has anyone ever played with quad carbs on a rover v8, does this give noticable power gains over the standard su's?

[eliotmansfield]

RPI used to make the boXer manifold for the rover, that used four SU's. It was supposed to be ok, But, and its a BIG but, it was a pig to set-up. Setting up a pair of su's is a pain, 4 is a nightmare. I think thats why he stopped selling it.
I opted for the weber(edelbrock) 500 carb and manifold, bolted straight on and was very responsive.
Eliot.
(quick google: www.rpiv8.com/sell-and-buy-pages-parts.htm#Boxer)

>> Edited by eliotmansfield on Wednesday 23 July 21:02

[GreenV8S]

ew_topcat said:

has anyone ever played with quad carbs on a rover v8, does this give noticable power gains over the standard su's?

I know somebody who runs quad webbers and somebody else who gets even more power from twin SUs. The SUs seem to be more tractible under part load conditions. I think the big advantage of cars is a good manifold with upstream fuelling (so you get plenty of charge cooling). Seems to me the difference between different carb types is relatively small compared to the difference between good/bad manifolds.

[Fatboy]

Didn't the westfield SEight run quad twin dellortos?

Remember reading it in a magazine - think it was Max Power about 7 years ago...

[2 sheds]

Quad down drafts will give you ultimate bhp , the only minus point is they a prone to catching fire.
Tim

[kevinday]

GreenV8S said:

The SUs seem to be more tractible under part load conditions. Seems to me the difference between different carb types is relatively small compared to the difference between good/bad manifolds.

Totally agree with you Peter, I ran twin 2" SUs for my modded 240Z, resulted in 265bhp from a 2.8. This was almost identical to Weber or Dellorto'd versions. Main difference was in fuel consumption, an SU is better for this. If you know how you can also improve response from an SU by filing away the lip of the piston on the upstream side of the airflow. Webers and Dellortos tend to respond faster, simple physics of inertia is the reason.
Filing of the needles in SUs is also possible if you are a real expert, they need to be identically matched and usually one of the many hundreds of standard needles will be a good profile.