Edelbrock or Offenhauser ?

[beanpole]

Guys,

I am about to order a Weber 500 Carb Kit for my Rover 3.5, however which manifold do I use , the Edelbrock or Offenhauser ?. I have heard the Offenhauser is lower.

This is for a Sumo build.

Steve

[Dan]

I have an offenhauser dual plane manifold fitted (I got it as a pacakge with the carb from RPI), Even with the Weber a leveling plate and a 3" airfilter I still have clearance under the bonnet. mind I do have the engine mounted as low as possible.

I have no experience of the Edelbrock manifold so unable comment on the height difference.


Dan ~ http://homepage.ntlworld.com/danny.mann/

[kev]

try http://www.roverv8engine.co.uk/index2.htm This guy has a good reputation for the Rover, but he can be a bit long with his lead times.
regards
Kev

[maxGD059]

I have a webber 500 with an Edelbrock dual plane manifold & there's loads of room under the bonnet of my GD. Personally I don't think there's much to choose between them. The main difference is if you go for a single plane that is possibly going to be less tractable but better on the track.

Cheers

Richard
(It'll only be a 5 minute job)

[perky]

I have just purchased a Weber/offenhauser kit from RPI after taking much advice from a guy there called Holley (no not the carb !) and he advised this combination with a 2" air filter as this will ensure that you will have room to manoever on a SUMO.

Also the offenhauser is a better option because this is actually a John Wolf Racing (JWR) Dual Port manifold developed from and Offenhauser. Being Dual port this is effectively two manifolds in one casting, with the inside of the manifold runners divided horizontally to correspond with the primary and secondary fuel/air flows of the carb. The primary mixture is fed into the bottom portion of the manifold runners, giving high mixture velocity at low rpm. For full power, the secondary mixture from the carb is fed into the top half of the manifold runners giving maximum flow. In summary the manifold provides the correct mixture flow/velocity for the engines needs at all throttle openings.

you need to be aware that the throttle cable suppied will need the end modifying for a Sierra pedal

Hope this helps,

[russell_ram]

I agree with most of what you say about the dual port Offenhauser/TWR manifold. However, in my opinion it is not as good a performance manifold as the Edelbrock. The ports on an Offenhauser are small to start with and then are further compromised by the splitter, and they are difficult to 'open out' because of the splitter. True, it probably gives a slightly more tractable performance characteristic than an Edelbrock manifold but there's not much in it.

In terms of height, again there's only 1/4inch in it although the Offenhauser has a very pronounced tilt down to the front of the engine which will probably require use of a leveling plate - the Edelbrock can nearly always be installed without one. Using a leveling plate makes the Offenhauser taller than the Edelbrock!

As Kev says, THE performance Rover/Holley manifold is the Wildcat item which is similar in design to a Huffaker tunnel ram design but with a built in thermostat/head bleed coolant circuit. Can't comment on height though yet - but I'm waiting for one in the post for a slight re-work of my engine. Definately not in the same 'low end tractability' as either the Edelbrock or Offenhauser though but I wouldn't consider my engine particularly tractable anyway!

Anyway, my choice between Edelbrock or Offenhauser would be to go for the Edelbrock everytime.

Russ