Weber carbs

[jerry and kathy smalley]

I have solex's on my sc engine and fight the usual low rpm lag. Will webers fix that, if so what do you recommend. I have b s car with zenith that is much better at the lower rpms. Recomendations?

[Martin Benade]

That’s pretty much the nature of bigger carbs, either brand. The Solexes are jetted correctly, switching to Webers maybe you could get them jetted correctly but that’s hard to count on.
The same cam is used in a 1600S with smaller Zeniths, giving a fairly reasonable lower end.

[Phil Planck]

Perhaps you can share current jetting, accel pump output and float level. I have same carbs on SC spec engine and dont have that problem.

[Martin Benade]

It’s partly a matter of taste. I consider my similar S90 to have OK low end torque but below 3000 rpm it is pointless to give more than about half throttle. Too much doesn’t slow it down but it doesn’t make it accelerate any harder either.

[Wes Bender]

Blanket statement (YMMV): The Zeniths have always been known for good, smooth low end acceleration, Solexes good for high end power and Webers also good for high end power, although they seem to have a narrower atmospheric pressure band than Solexes. I.e. you might have to change jet sizes more often with Webers as you change altitude. They're all subject to correct jetting. It really depends upon what your driving requirements are.

[Glen Getchell]

Ignoring my current carb issues on a different thread, I don't have the issue you are talking about with either 356 (one with Solexes and one with Zenith's) or any in the past with Solexes. I suspect a tuning issue.

My buddy with a Speedster put it into perspective best I think when he said "My Speedster with a 912 engine and duel Solexes has more carburation then my 1966 Mustang with a 289 and a 4 barrel."

So think about that. That's a lot of carb on a little engine! So obviously if they are not in tune you can have a problem. In my opinion the original type carbs correctly tuned are the way to go. And Webers on 356's have their own well known issues. To me the only advantage to the Weber is that its new in the box.

Glen
64Cx2

[Jim Kaufmann]

I'd check the float level on the Solexes first. If high you'll never be able to dial in the carbs correctly. As Phil mentioned accelerator pump, too much or too little quantity could be the problem. If the throats and butterflies are very worn, that will create low end issues also.

[Phil Planck]

I will add that having my carb bodies rebuilt by 356 Carb Rescue probably contributed to their smooth running at all rpms.

[Robert Reed]

Jerry; I have 40 IDF Weber’s on a Super 90, and it pulls from bottom to top smoothly. I have 28mm venturis which I think helps with the the lower end. It’s been many years since I changed from the Solex carbs, and have not had any issues.
I have 50 idle jets, 120 main jets, 200 air correction, f11 emulsion tubes.
I know that there are some members here that will tell you that I am some kind of heretic because everything that came out of Stuttgart is gospel. I don’t care what they may say, it’s my name on the title and I enjoy it the way I have it.
I will recommend that you use the original intake manifolds with adapters, do not try to use aftermarket manifolds.
Bob

[John Clarke]

Dellorto DRLAs run very well with no flat spots, 36 DRLA Dellortos with 28mm vents will work very well with lower states of tune.
We run the Dellorto 40 DRLAs on our 912 engine with the raised tower Idle jets to stop them clogging, with Spray Bars.
Don't fit the IDF Webers you will go down the rabbit hole of F11 V F7 / flat spots etc
Dellorto DRLA The Best Carbs ever for the 356, But finding them is now getting difficult.
Just I.M.H.O
Regards Jay

[Cliff Murray]

Weber builds such a poor product that Porsche installed them on many 4-cam cars and used them to tame the 911.

Yes the aftermarket manifolds for Webers are not good and the adapter plates on the stock Solex manifolds are much better.

The easiest solution to worn old original carbs is to send them to Jim at Carb Rescue. You don't need to have any tuning skills to make them work well.

[John Clarke]

Yes Cliff
To quote Bob Tomlinson author of the Dellorto Tech book, 'First there were Webers and Then there were Dellortos' ,
when asked about the change of preference.
When there was Only Webers You used Webers
Cheers Jay

[Phil Planck]

Jay
Where can I buy new Dellorto carbs?

[Al Zim]

You cannot solve your situation with a 55 year old engine, with a distributor and carburetors to match. for instance you cannot make the engine run smoothly with a 50++year old distributor and 25 year old spark plug wires. Start at the beginning with a leak down test and see how strong the mechanical portion of the engines is then work on the auxiliaries of he engine slowly and carefully to return them to OEM specifications. If you are lucky plan on a 2 week stint ( working daily) to figure it out. Be patient parts suppliers are having the usual inbound shipping situations.

[Keith Brooks]

I got lucky and bought the exception that proves the rule! A barely used set of Dellorto drla 40s that had been pulled from a VW 1915. I switched to some old Dellorto manifolds I had, scored some air cleaners and bolted them on to my fresh 1720 with a engle 110 cam and vintage speed sebring exhaust and I couldnt be happier, I didnt check the venturi or jet sizes but it has nice idle no flat spots and OK fuel economy, its smooth and STRONG!
. I have a decent mostly complete pair of Dells if someone needs em