Chris289

Ok guys, managed to find the correct 4bbl intake for my 56 now I want to run a modern carb, in my opinion carb technology has come along way over 60 years and i want to run an edelbrock performer series carb, I use them on mustangs and like them plus the carbs them selfs and spare parts are readily available in the UK at several places. My question is, what size are people running on a stock 56 324 olds? Only mod will be electronic ignition. I was thinking a 600cfm should perform well but the 650cfm could be too big?

Second question, I've seen others run the edelbrock carb, do I need a base plate adaptor for this or do they bolt straight onto the intakes? I believe the actual bolt pattern fits but thought the bore sizes were different to the later muscle car engines but could be wrong. I've seen adaptors on ebay to fit modern carbs onto the early buick nail head engines and the same advert also list it for the olds 324 engine but wasn't 100% sure if I needed one.

Thanks guys

47 Convertible

324 Olds makes its maximum horsepower at 4400 rpm and maximum torque at 2500 rpm. With this data you can use this calculator: http://www.thecarburetorshop.com/Car...eselection.htm to find out how many cfm would be optimum for your engine. 600 is more than enough and 500 might give much more efficient running without hurting horsepower. The information in the link above will lead you to this conclusion.

Re. carb fit on manifold: Why not go on line and contact the Edelbrock Internet site and go to their Tech Service and ask them for advice. Have the measurement of the bolt hole spacing on your factory 4 barrel manifold. Measure center-of-hole to center-of-hole.

Let us know what Edelbrock says and how it works out.
Jerry

Tedd Thompson

I have seen it done with a Edelbrock but the owner was still complaining about the carb to transmission kick down adjustments.I'm not sure what you hope to accomplish with a newer carb (not that the 4gc was the best ever made) but the improvements would be very small and a rebuilt well tuned Rochester will get just about as much out of a 324 as can be got.....Tedd

Chris289

Thanks guys, I went on the edelbrock web-site, hadn't thought to do that. There is no online or e-mail tech support for that sort of thing, being in the UK it's easier to e-mail or ask on forums.

My reason for wanting to go down the edelbrock route is 1: I don't have an original 56 4bbl carb, I'm upgrading from 2bbl to 4bbl so would have to source an original then rebuild it which would probably be cheaper to buy a new edelbrock in the first place.
2: edelbrock carbs and spares are readily available in the UK at most US car parts specialists.
3: I'm a believer of technology advances over the years (don't want to get into a debate on why not fit fuel injection or a modern engine then) and a brand new carb must surely must be more technologically advanced than a 60 year old one.

Just trying to work out what size I would need and if need a base adaptor, I can fabricate new linkage pieces once I've got the carb on the intake, one of those I'll cross that hurdle when I get there things.

47 Convertible

Chris you should be able to source information on bolt spacing on the Edelbrock carb you want and you have your manifold so can measure the threaded mounting holes in that. If they aren't identical you will need some kind of an adapter.

FWIW, The Edelbrock performer is basically a copy of the old and discontinued Carter AFB carburetor from about 1960s so its not a new design. Edelbrock may have upgraded some of the internals over time. I sure hope so because the AFB that came on my then new 1965 Malibu SS 327 was OK but not really dazzling in any particular way except fairly easy to tune. I think Weber makes the Edelbrock Performer carburetor under contract to Edelbrock company.
Jerry

Chris289

Jerry, I know the actual mounting bolt holes fit the intake threaded holes, I found that info online, the info I can't find is if the actual 4 holes that the air and fuel flow through in the intake are the same size as the ones on the edelbrock carb. From my readings online it seems the 56 intake 4 port holes on the top of the intake are classed as a 4bbl small rochester where as the edelbrock is classed as a large 4bbl found on the later muscle cars (mustangs etc) which is why it's possibile I need an adaptor that makes the 4 port holes line up and then the air and fuel flow correctly and the carb butterfly's don't foul on anything.

This is the one I saw on ebay:
http://m.ebay.com/itm/131411116323

If the 4 holes are the same size then I won't need an adaptor and the carb will bolt straight up.

I can't measure my intake yet, it's coming from the USA by boat so will be a good month yet before I get it.

Ah yes I know the actual style/body of the carb is an old design but it's the internal changes, the modern design inside that I mean. Take comparing the original 68 ford 302 engine to the 90 ford 302 engine, it's the same thing yes, but one is far more advanced than the other when you open it up. That's my way of looking at it anyway

I'm not looking for a performance upgrade by doing this, (all though if it gains a few ponys over a stock 4bbl carb I won't complain) just a modern reliable unit that if it has a problem or fails, I can pick up a new one or the worn part within an hour.

Many thanks for your help.

Dave B

Hello Chris289.

I have upgraded my 57 Olds to an edelbrock, there is some fettling work required to open the chambers from Edelbrock gasket size tapered down to original internal size. Only the top 1/4 inch depth will do.

You will also require a 1/2 inch spacer plate with the 2 hole option as the nearer holes are for your set up.

I had to play around with the kickdown but it all works bang on now.

I see you are in the UK, me too are you at the hayride July 24-26, I'm frantically fixing my Olds to be there and you can see the work involved.

Here's a couple of helpful pictures in the meantime.

Chris289

Hi Dave, thanks for the info, see this is the thing I was on about:

http://m.ebay.com/itm/131411116323

I believe that does the work for you in regards to tapering the manifold chambers and lets you mount the carb too.

No won't be at the hotrod hayride this weekend, my car is much rustier than I thought, allready both front floors and toe boards, drivers rear floor is done, currently doing the drivers rear inner arch and lower quarter repair then can move to the other side then some repairs in the trunk floor then move onto fixing the mechanical issues which I can't express how much I really just want to get on with. Sick and tired of cutting and welding!

Also were in the UK are you?

Chris.

Dave B

Hello Chris289.

That piece looks like it'll do the job, if it was me I'd drop the bloke a quick email explaining your preferred set up to get 100% confirmation it'll work.

I'm just the other side of the Thames in Kent.

Here's a picture of the finished job on my 57.

Regards.

David.

Chris289

Hi Dave, the work on your intake looks good. I found this one summit do, looks the same and a lot cheaper:

http://www.summitracing.com/parts/trd-2064/overview/

I may get that one and my carb at the same time, need to order some buick engine parts for a customer soon so will grab it all from summit at the same time.

Out of curiosity, which edelbrock carb are you running on your 57, I know your engine is a 371 but just wondered what size you went for?

Dave B

Hello Chris289.

Currently running 1405 600 cfm performance, had to richen up as have mild street cam in there. Goes well.

Think a 1403 or 1404 500 cfm would be better suited to your engine if standard.

Hope this helps.

Regards.

David.

Chris289

Hi Dave, yeah I was using some online CFM calculators and seemed a 500cfm was the conclusion every time. I'm going to try that