Vintage GT350 Weber manifold with Webers

[tbone1209]

Hi- new poster. I have an old timer hot rodder buddy that has what a[ppears to be an original Shelby quad Weber manifold that he purchased about 20+ years ago when he had his GT350. It's been sitting in his warehouse and he now is thinking about selling the set but doesnt really have any idea what it's worth. I've attached some pics I snapped of it and some old pics of his 350 with it on.

Could someone give me an idea of what its worth, assuming it's not a copy?

Thanks!

[tbone1209]

more pics

[SFM5S000]

Hello tbone1209,

The manifold is a later "Shelby" catalog item. Depending on the series of the Weber's, there are stamped numbers on the flanges of the base on each carburetor. Can you post a pic or list the two sets of numbers of each carb. That would help tremendously on determining their value.
There are a few Weber guys here on the forum, myself included.

Cheers,
~Earl J

ps, one of the velocity stacks seems to have been modified (shortened) It looks odd. I have a few spares. Shoot me a PM I'll send you one free/no charge but you pay the postage. $7.00 I think.
~E

[JD]

Here is a photo summary of some of the Weber variation that was posted on the forum before (may have been Dan Case?) 

It may help with identifying the version of carbs your buddy has...

(seems to be the 4th version 1970 or later, others will know better)

[JD]

images rotated... hope that's OK, can delete if you want

[shelbydoug]

The carbs without the cast in mounting side tabs (JD calls bosses) are more desirable to the Cobra and GT40 guys. The lack of tabs dates them generally to the mid 60's or so.

Other then the tabs, they are functionally the same providing that the casting says made in Italy and not made in Spain. Spain castings are a recent phenomenon and not from the '60s or even the '70s. Sometime in the '90s I think?


The SHELBY manifold is desirable to the "Shelby guys" but so is the COBRA casting.
One thing is that you can't say that the manifold is a "reproduction". No one to my knowledge is recasting the SHELBY lettered version.


If you can see the COBRA lettering on the water neck when installed then it is correct for a "Mustang" application but as far as I know, never offered originally by Shelby and something that Inglese worked on around 1980 at getting made BUT is very desirable for a Mustang installation.

Initially the Shelby(Mustang) installation was using the COBRA water neck and just turned upside down so you couldn't see the COBRA logo.


Most Weber setups that I have seen selling are going to trade in the $3000 to $3200 vicinity and that would be a fair price.

The GT40 manifold is a different story. It has no performance advantage but is a unique casting and engineering number.


Small parts like rod ends in the linkage are not significant price wise if they need to be replaced. Even velocity stacks are nickle and dime items.

The main thing is that all of the castings are undamaged.


The early carb castings, which these are not, are worth more but it's difficult to put a number on them? Maybe $500 more for the set? Opinions will vary on that one. Many won't care about that detail.

SOME very early '60s carbs are serial numbered. There is a small but exclusive market for those. You could probably name your own price for those carbs since they would probably be going on factory race cars?

They will be stamped on the mounting flanges IDA, IDA-1, IDA-4. The IDA-1 will be the GT40 "original application" carbs, but the carbs in the pictures have tabs so they are not those carbs. Most likely stamped IDA-4.


If any of the carbs need servicing, then that's on you. It generally doesn't affect the value significantly. Most parts are available and the IDA's are not like the Holleys in drying up the bowl gaskets because there are no bowl gaskets.

The largest, most common problem that used carbs have are twisted throttle shafts. They are made out of soft brass and twist easy with too much throttle return spring pressure. You can get replacement shafts for them now but they aren't cheap.

[tbone1209]

Thanks for all the info and offer for the velocity stack! I think think the owner has a few extra.

Snapped some more pics of the manifold and Carbs yesterday. I don't see any casting identification aside from the Shelby logo. Where would the "made in ****" info be located? He said he's had the setup for well over 35-40 years.

[tbone1209]

More pics 👍

[shelbydoug]

The carbs are IDA-4's. Bologna, Italy.

The manifold is a Buddy Barr and they are usually marked that underneath on the bottom of the manifold.

I'm not that familiar with the Shelby logo version. I never had one in my hands.

SOME Buddy Barr castings have no id's on them. MOST do.


He has the COBRA logo waterneck which was made for the 289 Cobras and to use it on a Shelby/Mustang, you need to turn it upside down with the COBRA logo pointed down so you don't see it. It would appear from your photos that is exactly what is there.

I'd speculate that the COBRA logo was just machined off but maybe it was made that way, who knows for sure unless they were there at the time? The important thing is that it works. There are current reproduction waternecks readily available
if necessary. That is no kind of issue.

That makes sense since I don't think the Mustang versions were made until about 1980?



Look down the throats of the carbs. See if you see a number like 37 or 42. Stock that carb came with 37mm "chokes" or what Weber calls, "auxiliary venturi". Originals are cast and have size identification you can see from the top.

The GT40 version, the IDA-1 came stock with 42's.

Either one is fine but you may decide that for a 5.0L, you are happier with the 37's.
42's take a little torque out of the engine but give you noticeably more top end.



The date code is E6. You need to ask Dan Case what he thinks that is for.

The carbs have the tabs so I don't think they are from '66, probably May of'76? That would fit into the time frame that you suggested.



I don't see the linkage so I can't comment on that but the 289 Cobras used a center shaft with clamp on throttle arms for the carbs. That's what the two threaded bungs are for on center of the manifold.

A Shelby would use a side mount bracket bolted two the studs between the left side carbs.


It's a nice set up and should clean up well and easily.

[tbone1209]

Thanks for the info Doug. The water neck has the cast platform which would normally have the "Cobra" cast in but the platform on this neck is completely blank. I've attached a couple pics down the throats and the linkage.

[shelbydoug]

The linkage is a little "unique". I haven't seen that type of bellcrank and NEVER saw a throttle rod bent like that from bank to bank.
That really kills the ability to fine adjust left to right and sync them correctly.

I think with this set up, 1) the entire assembly needs to be vapor blasted 2) carbs gone through 3) linkage replaced entirely and 86 the fuel line set up.

So if you send it to Inglese about a thousand bucks for that? If carbs need throttle shafts, bearings, or a couple of brass floats more.

You're missing a couple of heat insulator gaskets but at least who built it knew the need? That probably means they have Gene Berg glass ball inlet valves too? They found out about fuel boiling and causing big time flooding.


Those are the K&N air filters. The thing is that you can't use air filters with individual runner manifolds. The overlap of the camshaft pushes fuel back out of the carbs. The filters will get saturated with atomized fuel and when you go to restart a hot engine, there is flame travel (not backfire) through the intake manifold and it will ignite the filters.

Sell 'em to the VW guys. They love'em on their dune buggies.

[Dan Case]

The carbs are IDA-4's. Bologna, Italy.

The date code is E6. You need to ask Dan Case what he thinks that is for.

The carbs have the tabs so I don't think they are from '66, probably May of'76? That would fit into the time frame that you suggested.

To me E = May and 6 plus the die cast zinc accelerator pump jet assemblies are most likely means 1976. In my notes zinc assemblies show up the first time in April 1971.

The original E. Weber manufacturing company dropped serial numbers by September 1970 and continued with date codes from them on. 

The "SHELBY" lettered intakes, carburetors, or complete induction systems were sold by parts businesses Mr. Shelby owned or partnered with (Autosports® comes to mind) and all the major mail order catalog 'speed' businesses and places like Sears, Roebuck, & Company® and Montgomery Ward® between mid 1968 until about early in 1972. The hitch, "Shelby" sold 48 IDA1 models for Ford V8s. In the 1966 catalog Shelby American claimed they were the sole importer of 48 IDA1 models.  Shelby American and Ford Advanced Vehicles used and sold IDA and IDA1 models in any mixture over their entire period of using new ones. (48 IDA and 48IDA1 models are exactly the same part for part except for which throttle lever E. Weber installed.  The levers E. Weber installed did not matter as Shelby's works and FAV replaced them with new levers of their own designs anyway.)



A vague reference in material published by  E. Weber in Italy (in Italian) indicate that the IDA 2C (two choke) models were created for GT40s.  I was hearing in the mid 1960s that Ford money paid for the tooling and came with the plan to buy one thousand carburetors over the life of the program. 48 IDA / 48 IDA1 models both used 42 mm chokes. (If you use the E. Weber system design guide formulas the maximum size choke a 289 Ford would require even at high volumetric efficiency is 41 mm.) The ready for manufacture drawings for the 48 IDA were signed off late in 1963. The first carburetors didn't get to Shelby until about late March or early April 1964.  The first version of factory over haul kit listed the application as "Type 48 IDA-IDA 1 FORD Cobra Lotus".  My translation right or wrong is GT40, Cobra race cars, and Lotus 30 (all powered by 289 c.i.d. 8V engines at the time).


Dean Moon's businesses (multiple) made 48 IDA 1 models available by 1965 and well as intakes for all kinds of applications. Moon also sold "Cobra" 289 Ford induction systems. Circa early 1966 Dean Moon released 48 IDA4 models. I have some handwritten letters between Moon and a potential customer. Along with the letters was the offering of 48 IDA4 models for engines of too small displacement to use 48 IDA1s. 48 IDA4 models left Italy with 37 mm chokes. (There were also 46 IDA2 and 46 IDA3 models for even smaller engines.) By 1967 Geon® started offering 48 IDA4 models as service replacements.


For the Boss 302 engine fans there was a "CS SHELBY' lettered intake after Boss 302 Mustangs came out.

[tbone1209]

Thanks Dan. Appreciate the info. Here are a couple picks I took today of the underside of the manifold. There didn't appear to be any information on the bottom.

[shelbydoug]

When anyone is discussing the size of the chokes, they are talking about "tuning".

I like 40's but 42's on my Cleveland are ok also. It depends on your likes and the engine displacement.

I can't see the numbers in your pictures because of lighting but I think those are 37's? Those are fine.


I remember when Gary Hall was selling complete bolt on systems for Panteras, he was supplying them with 32's. I don't know anyone with that setup so I don't know how those run but I would speculate that the engine runs out of rpm around 5500 to 6000.

I remember taking a demonstration ride in Andy Carr's Pantera around 1982 when Jim Inglese had it in "the shop" setting the Webers up in the car. I was never told what chokes were in it. It was very torkie. Probably 37's.

I haven't heard of Andy since?

[Dan Case]

Thanks Dan. Appreciate the info. Here are a couple picks I took today of the underside of the manifold. There didn't appear to be any information on the bottom.

You are welcome.