More questions about Weber Carbs

[Chasedan]

I've been reading the posts in this site about the Weber Carb retrofit / replacement for the Solex 32 PAIA. I was planning on re-using my original Solex if I can figure out how to get the secondary throttle to operate right. When the car was running (about 20 years ago) I had a large rubber band (seriously) attached to the secondary throttle linkage and wrapped around the secondary vacuum diaphagm body. The effect was to provide a little extra up-force for opening the secondary throttle. The draw back was that sometimes there was a time lag from the moment I released the throttle to having the engine actually slow down. It sometimes made it interesting in stop and go traffic.

My questions are:
1) What is the recomended Weber replacement for the Solex 32PAIA? I have visited Webercarbsdirect.com and there seems to be a few variations on the 32/36 DG**. My Alpine is serial number B94000037. The engine is the original 1592. I am in process of rebuilding, .030 oversize pistons, original crank, reground original cam, original connecting rods, new bearings, original oil pump.

2) What is involved in adapting the Weber to fit my engine?

3) Is there any value in keeping the engine "Solex ready" in order to keep the car original equipment?

4) Is there any performance advantage to the Weber over the Solex?

Thanks in advance for any advice.

 

[Alpine Bob]

Just for one advantage, I bought my series IV 8 years ago, it had a Weber carb on it, I just replaced the engine with a 1725, removed the Weber and intake off the 1592 and bolted it in the 1725, and still hasen't been adjusted yet. Is this an advantage, you "betja" it is, there's too many other things on an Alpine that need attention.

 

[65beam]

weber carb

i have several cars with the 32/36 weber.it is a direct bolt on to the series 4 intake.it requires one minor change to the linkage at the point where it fastens to the carb.the end needs turned about 90 degrees.about 30 years ago i clamped it in a vise,heated it and bent it .still on the car.if you ever wanted to put the solex back on ,which is not a good idea, you only need to redo the linkage.with all the possible problems with the solex,you would be wise to turn it into a paperweight.the solex is one of the worst carbs ever built .the the vacuum unit comes loose , the starting valve falls off ,jets come loose and end up in the valves,plus they leak fuel so bad that my car caught fire at an early age. put the weber on and enjoy trouble free driving.

 

[lemansvk]

Chasedan;

I'm not sure that there is a "recommended" downdraught Weber for the Alpine, but several people have told me that the 28/36 variant (fitted to early Cortina GT and some Fiats) produces the best results in terms of response, performance and economy because of the smaller primary. However, these are scarcer than the 32/36 which was fitted to many Pinto engined Fords.

My Alpine has a 32/36 DGAV (Auto choke - operated by heat from engine coolant) which has been converted to manual choke - there are manual choke versions around and much newer electric choke versions. For many it's a case of what they can find within a budget.

The Weber secondary throat is mechanically operated. Webers are truly 'set and forget' propositions.

As well as my Alpine I have a Vogue with same engine, but with original Solex. Compared to the Alpine its harder to start, hates running when cold (stalls easily), has less power. The Vogue is bigger and heavier so it's hard to compare fuel consumption but others tell me the Weber is better.

'Adapting' the Weber to your engine involves bolting it on, adjusting the linkage (I believe bending one rod is all that is needed), getting an appropriate air filter (I use a Lynx Ram-flo) and hooking up the fuel line - I think the inlet to the Weber is slightly larger than that on the Solex. Of course it will probably need to be jetted to suit your motor - I had mine done on a dyno at a trusted tuning shop.

The only advantage I can see to keeping the Solex is if you wanted to 'show' the car in concours events - the Weber would cost you originality points.

Cheers, Vic

 

[Wombat]

Vic

Do you know if anyone here in AU has tried the Weber 34 ADM off the XE & XF Falcons? The mounting bolt spacing is the same as the Solex.

 

[lemansvk]

Robert,

I should probably answer "No" to that question, but I have a sneaking suspicion that I know someone who either has or is about to do so (without them necessarily knowing so). It's a long and complex story and involves people in far places. Rather than spend 3 pages explaining it, I'll get back to you after I've asked some more questions.

Cheers. Vic

 

[Chasedan]

More Question:
Does the Weber have a good vacuum port for operating the vacuum advance on the distributor?

Grand Rapids ,MN doesn't have a dyno shop. The closest dyno shop might be in Duluth, about 90 miles away. Very few people around here have even heard of a Sunbeam, or Weber Carbs. Do I need to bring along a handful of various sized Weber jets or can jets from a Holley, Rochester, Carter,or Mikuni fit?

thanks again

 

[65beam]

weber carbs

finding the 32/36 may be hard for you guys down under but not here.the ones that suppliers here sell are already jetted for the alpines. at least the ones i have bought were.they were straight bolt on,adjust,and drive.on the road they give me close to 30 mpg,great response and are trouble free.i also run K&N air filters.

 

[65beam]

weber carbs

chasedan,
call rick at sunbeam specialties. 408 371 1642.im sure he can sell you everything you need.the 32/32 and the 32/36 do have the connection for the vacuum advance.other than the modification to the linkage ,they are bolt on.i run the same timing same everything and have since i installed the weber on my series 4 in the late 70's.i have never done anything to it since.i have three cars with this set up and i connect the fuel line to the carb with a short section of rubber hose and two clamps.i'm not sure why a dyno would be needed since these cars are all 40 something in age.fit the weber,drive it and enjoy it .

 

[Nickodell]

65Beam. In most cases it is a straight bolt-on, but some of us who have done the conversion have found an annoying and dangerous flat-spot, where the car bogs down and even stalls when moving off from stationary. The solution we have found is a larger primary jet than the 0.055mm one supplied. Rather than experimenting with, and paying for, a range of jets I used micro-tool drills (which I use in model making) to steadily enlarge the standard jet. I found that I had to go to 0.077mm before the flat spot disappeared. You need to keep the idle mixture on the rich end of the range, too.

 

[husky drvr]

65Beam. In most cases it is a straight bolt-on, but some of us who have done the conversion have found an annoying and dangerous flat-spot, where the car bogs down and even stalls when moving off from stationary. The solution we have found is a larger primary jet than the 0.055mm one supplied. Rather than experimenting with, and paying for, a range of jets I used micro-tool drills (which I use in model making) to steadily enlarge the standard jet. I found that I had to go to 0.077mm before the flat spot disappeared. You need to keep the idle mixture on the rich end of the range, too.

larger primary idle jet

 

[65beam]

weber carbs

i have said this many times; WHAT AM I DOING WRONG? i have converted three cars,no hesitation from the carbs right out of the box.they are trouble free.i have another carb in a box,maybe i should convert another car.maybe you guys are not using the right carb.do it right the first time and no problems.seems to work for me.

 

[jumpinjan]

I never had any problems with the Webers, right out of the box either. I haven't experienced this flat spot off idle until I drove the car after it sat for about 2-3 years (engine was apart to rebuild it). After I got the new engine in and fired it up, I had the flat spot syndrome. I wonder it is could be deposits in the pilot jet? Ian's old white, seriesIV automatic, had a very bad flat spot, the worst that I ever seen.

 

[Nickodell]

larger primary idle jet

Oops. Quite right.

 

[husky drvr]

I never had any problems with the Webers, right out of the box either. I haven't experienced this flat spot off idle until I drove the car after it sat for about 2-3 years (engine was apart to rebuild it). After I got the new engine in and fired it up, I had the flat spot syndrome. I wonder it is could be deposits in the pilot jet? Ian's old white, seriesIV automatic, had a very bad flat spot, the worst that I ever seen.

Jan,

I'm curious, how was the engine different after the rebuild? Cam? Head and/or valves? Valve springs? Good valve job? Cylinders bored and new pistons and rings fitted probably having less blowby? Disassemble and clean or even eliminate the PCV? All of the above?

Any or all of those items could have changed the vacuum signal to the carb enough to require a different sized idle jet ( pilot jet ).

The only thing certain at this point is that virtually no Rootes engine is now as it left the factory. A new carb is going to have generic jetting close enough to allow the engine to run but probably in need of fine tuning. If someone has a carb that works well out of the box, then they have probably had it a while. Say from a time when more Rootes engines fit in with the factory performance baseline and Weber thought that carb conversions for Sunbeam engines might have been a big enough market to worry about supplying a properly setup carb.


Just a few thoughts,

 

[jumpinjan]

Jan,

I'm curious, how was the engine different after the rebuild? Cam? Head and/or valves? Valve springs? Good valve job? Cylinders bored and new pistons and rings fitted probably having less blowby? Disassemble and clean or even eliminate the PCV? All of the above?

Yes, all of the above and in a 1600 Lemans engine.
In another case, I hopped up a 1725 with KB cam, lighten flywheel and so on, and never had the flat spot with the new Weber carb. However, I felt that the engine didn't "feel" right, like it was starving for gas off idle, so I went to Tiger Auto to change out the pilot jet to the next size. I did that and the engine ran worse, so I replaced the original jet back in, and marveled at how well the factory jetted the carb.
I have suspicions that the jet is susceptible to varnish, but I never had the time to inspect that carb on my Lemans yet.
Jan

 

[Alpine 1789]

I have suspicions that the jet is susceptible to varnish, but I never had the time to inspect that carb on my Lemans yet.
Jan

You may be on to something Jan. I've noticed that my flat spot seems to disappear every time I put in a larger jet, then comes back some months later. I wonder if periodically spraying carb cleaner into a running engine would help?

 

[Nickodell]

Jim: for a reason only known to - well, I don't know who understands it really, but in the two Weber carbs I have owned I've the idle mixture tends to drift into the weaker end of the range in time. Over the years I've found myself readjusting the idle mixture screw out (richer) to get a smoother idle and acceleratiopn from rest. Just one of life's great mysteries (and no, I haven't developed an air leak anywhere).

 

[Chasedan]

Wow,
Thank for all the input. I was away from my computer for 1 day and look what happens.
I am going to install a Weber. Audios Solex.
Yesterday I had the huge dilemma of whether I should tork the Alpine engine head or take my kids fishing.
We caught 4 walleyes, three sunfish. We also threw back a dozen or so rock bass.
Thanks again

 

[Alpine Bob]

I believe you did the right thing, your kids are more important then a stupid Weber, you can work on it after the kids go to bed.