getting webers to work correctly Options

[Jgilliam914]

44IDF ...I rebuilt them (first timer) and I can't get enough fuel to flow through them. What are my next steps and who could I send them to to get them set up correctly?

[Jgilliam914]

float height was off so I will adjust this and see where I am at

[ctc911ctc]

According to:

https://www.performanceoriented.com look at the various weber posts, this is critical for the same reason you raised,

I recently did the same as you - looking forward to the results when I fire it up.

CTC

float height was off so I will adjust this and see where I am at

[Superhawk996]

44IDF ...I rebuilt them (first timer) and I can't get enough fuel to flow through them. What are my next steps and who could I send them to to get them set up correctly?

Not enough info to answer your question without info on engine size and Venturi size.

You’re starting from a disadvantage with 44’s unless you have some big bore / stroker.

[Jgilliam914]

44IDF ...I rebuilt them (first timer) and I can't get enough fuel to flow through them. What are my next steps and who could I send them to to get them set up correctly?

Not enough info to answer your question without info on engine size and Venturi size.

You’re starting from a disadvantage with 44’s unless you have some big bore / stroker.

96mm with a 74mm stroke

[Chad911sc]

I think if I remember correctly I set mine at 10.5mm. Mine are Webber IDF 40s.

[Superhawk996]

44IDF ...I rebuilt them (first timer) and I can't get enough fuel to flow through them. What are my next steps and who could I send them to to get them set up correctly?

Not enough info to answer your question without info on engine size and Venturi size.

You’re starting from a disadvantage with 44’s unless you have some big bore / stroker.

96mm with a 74mm stroke

Not big enough to support 44’s. What venturis?

[Jgilliam914]

44IDF ...I rebuilt them (first timer) and I can't get enough fuel to flow through them. What are my next steps and who could I send them to to get them set up correctly?

Not enough info to answer your question without info on engine size and Venturi size.

You’re starting from a disadvantage with 44’s unless you have some big bore / stroker.

96mm with a 74mm stroke

Not big enough to support 44’s. What venturis?

36mm with 38 sitting on the shelf in reserve. I figured it was a good starting point and adjust after I got it running

[Superhawk996]

Those Venturis are ridiculously large for 2150 cc.

You need stronger vacuum signal - you should be running more like 30mm for street use.

Even with 30mm Venturis 44’s hurt you bigly at initial throttle tip due to the larger butterfly’s.

[brant]

street car with street cam?

you'll need much smaller venturis to get those to work on the street

[Superhawk996]

Here’s the standard venturi selection chart for MAX horsepower. If you set up to this chart you’ll end up with (IMG:style_emoticons/default/stromberg.gif) driveability.

Street driveability is 4-6mm smaller than this chart would suggest.


Also going to give you this chart out of the Weber tuning guide (page 21)


Edit: clarifying the chart above - this chart from the Weber tuning guide is for total engine displacement. The point being that a vehicle like early BMWs from the 70’s often ran on 30-32 mm progressive carbs with small bore Venturis.

Here is the Weber tuning guide chart for single cylinder per barrel Venturi selection chart - basically the same as the Excel chart posted at the top, the main difference is the chart from the Weber manual has 6000 rpm as the lowest curve while the 5500 curve in the Excel chart is more appropriate to our 914’s.

[Superhawk996]

Download the Weber tuning guide and spend some time with it.

https://www.lainefamily.com/images/WeberTuningManual.pdf

Pay particular attention to understanding the progression circuit (page 10).

Weber IDF spend about 60-70% of their life running off the idle circuit / progression holes in street driving.

[Jgilliam914]

Download the Weber tuning guide and spend some time with it.

https://www.lainefamily.com/images/WeberTuningManual.pdf

Oh that should help. I've got. whole box of different Venturi's.

[VaccaRabite]

I had dual 44s on my 2056 for a while. 32mm vents IIRC (It was a long time ago).

It was a fun motor, but it was ALL top end. No torque at all below 3500 rpm, but at 4000 it was going to throw you back in your seat.

I swapped down to IDF 40s with 28mm vents and eventually got on the EFI train.

Zach

[DennisV]

What are my next steps and who could I send them to to get them set up correctly?

This 2-pager from Jack Staggs and Carburetor Rescue might help. He is very well known in 356 community. It's a practical setup and troubleshooting guide that I think applies to most any carb use.

[930cabman]

Those Venturis are ridiculously large for 2150 cc.

You need stronger vacuum signal - you should be running more like 30mm for street use.

Even with 30mm Venturis 44’s hurt you bigly at initial throttle tip due to the larger butterfly’s.

Ran into this exact problem with a fresh 2056 a couple years ago, just not enough volume of air. switched to 40IDF, 3 years and about 10k miles later all is very good

[NARP74]

Trust the knowledge-base here. You will disagree until you learn enough to know the truth. Ask me how I know... I'm stubborn, but I get there in the end.

[porschetub]

Those Venturis are ridiculously large for 2150 cc.

You need stronger vacuum signal - you should be running more like 30mm for street use.

Even with 30mm Venturis 44’s hurt you bigly at initial throttle tip due to the larger butterfly’s.

(IMG:style_emoticons/default/agree.gif) well said , sadly in this case they will end up in the FS section ,they don't have a place on a motor that size ,however you deal with it the airflow will be wrong .
Cheers.