Holley or Edelbrock/Weber

[Bernie]

I'm creeping up to that point where I have to spend £500 or so on the top end of my 3500 Rover V8 rebuild.

It's going to go into a Sumo, and apart from replacing appropriate bits, the only change I've made is to put in a Viper Hurricane cam. Having read the very strong opinions of someone on the RPI site, (http://www.rpiv8.com/carbs-1.htm) I decided on the Weber, but that I would buy the Edlbrock equivalent at Real Steel, where I paid for the discount card.

Declan at Real Steel has been excellent with support and advice, and saved me lots of cash, but he disagrees with RPI, and showed me an Offenhauser chart which shows that you need a 390 Holley. Real Steel are Holley distributors, so maybe you would expect he would try to sell me one, but so far the cash he's saved me would have been spent with him, and he could sell me the Edelbrock anyway.

So what do people think, and what experience do you have?

[breskit]

It's my understanding that the Webber is much easier to setup and gives you less trouble getting the engine running.

For my Sumo, I also went for the Webber/Offenhauser combination. All I needed to do was simply plug it in and turn the key. It started first time, every time. It cost me $495 + VAT but has given me absolutley no problems. It also came jetted correctly.

The only little piece of confusion I had was plumbing it in. On the standard Rover manifold there is a pipe that runs underneath to the heater. There is no room for a metal pipe under the Offy, but they do supply a rubber pipe which does the job beautifully.

HTH.

Tony B
(Still working on my clutch. Can someome tell me which way round the clutch plate is supposed to sit? Ta.)

[wilf]

Bernie - generalities on Holley vs Edelbrock first:

1/ Holley is a much more "adjustable" carb than an Edelbrock, in that you can fine tune them more
2/ Edelbrock much simpler to set up.
3/ Holley has gaskets in its construction below the fuel level, Edelbrock does not - can sometimes lead to leaks, but not really a major concern.
4/ No "power valves" in the Edelbrock - these can give trouble on Holleys - they are not "backfire-proof".
5/ Far greater range of carb sizes available from Holley.
6/ Fuel level far easier to set up on Edelbrock.
7/ In the main, engine tuners know more about a holley than an edlebrock.

Specifics on the RV8 - The 500cfm Edelbrock carb is, in theory, too large for a 3.5 RV8 - hence the recommendation from Real Steel to go for a 390cfm Holley. Having said that, many folks have fitted that size edelbrock without problems - indeed many have found them to be right "from the box".

Summary - if you want to get the last drop of horsepower from ahighly tuned engine, then a holley would be the way to go, but you would need significant experience of twiddling holley carbs to get the very best from them. For an engine in a reasonably basic state of tune like yours - go for the simpler carb.
I use an edelbrock 800cfm carb on my car, have found it to be excellent, very easy to dial in (I adjusted it myself on the rolling road after reading the handbook! - it took one jet change on the secondaries to be right). Only problem I have at present is fuel surge on hard right hand corners - really only noticeable on a track.

Last thought - the above is my personal opinion - and you will read different opinions here no doubt. Ultimately it's your money!

Wilf

[StuartH]

Bernie,
I had a weber/edelbrock 500cfm (from RPi) on my 3.5 rover and it was great - it's now on my 4.6 rover and (with a jet change) is still great - off to the rolling road next week for some final tweeks.
A tuning bloke in the garage I spoke to much prefered edelbrock to holley because he reckoned holley's flood easily and are a pain to set up.

Stuart

[robert]

Wilf

Fuel surge is a common problem, and can be attributed to 2 reasons. Lateral or Longitudinal G forces (Cornering) or a slightly high float level.

With a slightly high float level, the fuel can come through the whistles, but as you are not experiencing the surge under braking, then the G force could be your issue.

I know holley sell a set of baffles to stop this, and in most souble pumpers, this is part of the kit as standard. I had a quick search on Edelbrock but could not see anything suitable, so a call to Repower might be your option, or a set could be made up.

Robert
Forum Admin

http://www.cobraclub.com/flags/UK.gif

[Happy Jim]

>Tony B
>(Still working on my clutch. Can someome tell me which way round the
>clutch plate is supposed to sit? Ta.)

Tony,

The clutch plate should have "Flywheel Side" stamped/engraved on it if it's from the Rover V8

Cheers

Jim

[wilf]

Rob - I have seen the anti-slosh baffles for Holleys, have not been able to find an equivalent for the Edelbrock. I have been lowering the fuel level gradually, some improvement, but not a cure yet.
The issue appears to be that there is an internal path in the carb for fuel to run from one float bowl to the other (float bowls are side mounted, not fore and aft). I might just try blocking that up, or at least, leaving a small orifice to allow air to flow, but not so much fuel.

As I said, it's really not too much of a problem on the roads, only at full lateral g on a track (and I rarely get anywhere near that on the roads, I still have some sense of self preservation left).
Now the car is painted and polished, not sure how many tracks it's gonna see!

Wilf

[robert]

Is there a fuel rail? Or do you have dual feed?

Robert
Forum Admin

http://www.cobraclub.com/flags/UK.gif

[interestedparty]

I would like to make a comment about the manifolds. The Offenhauser which is often reccommended, especially if there is limited under-bonnet clearance, is a 360 degree design. This means that both sides of the carb feed into ythe same plenum, and each inlet port can see both carb chokes. This arrangement is good for airflow at high rpm, but the drawback is too much air flow at low (street) rpm resulting in low gas speed and poor cylinder filling, hence poor torque. The edelbrock (performer) manifold is a 180 design, similar to the original rover setup, each side of the carb feeds 4 cylinders. Not so good at high rpm but ideal for street use. What I like in an engine setup is the ability to drive around at a comfy 2 to 3000 rpm, and , when the opportunity presents itself, to floor the accelerator and get a good strong rush of power with no flats spots or hesitation. The edelbrock (weber) 500 on an edelbrock performer manifold provides this. It worked great straight out of the box on a 3.5, and when I swapped it onto a tuned 3.9 it didn't even need a jet change (checked at my usual rolling road, Owen Developments in Oxfordshire)
John

[wilf]

Yes - there is an internal fuel rail, basically a drilling in the top cover, to supply both needle valves from one side, single feed. But there is, I think, (and I'm going to have to whip the to off to check because my memory is going), another connection, separate to the internal fuel rail, which essentially connects the two float chambers. This is where I think fuel floods across from one float chamber to the other under high(ish, this is a Crendon, not a GD) lateral G. I think I might arrange for a fuel jet to stop up this connection - will allow air to pass (and I suspect that air presure balance is the duty of this connection), but not too much fuel.
I have already changed the needle valves for "off road" types.

Not a pressing problem, just one of those "tweaks" you do.

Wilf