Webber 32 / 36 Set Up Recomendations

[androvers]

I know, I know, search the FAQ, and I have. Maybe not well enough?, Likely.

 

My car info is this currently, Ireland engineering 9.5:1 Pistons, oversized SS intake and exhaust valves, 292 reground cam with oversize eccentrics, HD rocker arms, 5 speed conversion and has a Webber 38 / 38 carb that runs well and strong.

 

The car came with a Webber 32 / 36 that the previous owner said was needed for smog / DEQ.

 

I took the carb apart today and it looks to be in good shape this is what's inside:

 

Primary Main Jet 145

Secondary Main Jet 140

Primary Air Corrector Jet 170

Secondary Air Corrector Jet 160

Primary Emulsion Tube F50

Secondary Emulsion Tube F6 (I swear it says this)

Primary / Secondary Venturi 26 / 27

Primary Idle Jet 65 (says RCA 65?)

Secondary Idle Jet MISSING!

Primary & Secondary Aux Venturi 3.5mm

Needle Valve 200

 

I would like to set up this Webber 32 / 36 for long distance trips with the goal of great gas mileage primarily. I have a trip to a friend's wedding in Nebraska Planned in May (I am in Oregon) and wanted to drive out there and visit some friends in Wyoming on the way. If there is a recommendation that would also help pass DEQ with the same set up that would be great but primarily thinking gas mileage at this point. Was unsure if C.D. Diesels recommended settings were what I should go with for good gas mileage with my engine build. Any thoughts links or rebuking is welcome. 

 

 

[Simeon]

CD's prescription is generally considered to run a 'bit rich' but should be a reasonable match for your car.

 

How you drive it and things like weight carried, ignition timing, tyre pressure/ windows rolled down etc will effect your mileage more (unless your carb jetting is just plain wrong and it is washing your bores with fuel). Your jetting will end up either being right or wrong. Right will mean best mileage and best power. 

[androvers]

Thanks Simeon,

 

Will go with C.D.'s recomendation as a starting point I think.

[71bmr02]

I just rebuilt and installed a 32/36 man. choke and went back with baseline weber factory settings as follows;

(all numbers are in primary/secondary order)

 

main jet   140/140

emul. tubes f50/f50

air correction jets 170/160

idle jets 60/50

pump jet 50

float level 35/51 plastic  51/41 brass  (mm's)

 

c.d.iesel recommended on this forum (2013)

main jet   140/170

emul. tubes no recommendation

air correction jets 145/175

idle jets 60/55

pump jet 50

float level 40mm

 

a well known weber performance rebuilder

main jet   150/190

emul. tubes no recommendation

air correction jets 150/160

idle jets 55/55

pump jet 50

float level no recommendation

 

I have only had the weber factory settings on the street for a couple of days but can honestly say i'm pleased with the performance and hopefully gas mileage.  My other setup was closer to the performance builder numbers and gas mileage wasnt that great and performance wasnt that much better.

do a google search for   proper and only way to tune a weber 32/36   there is quite a bit of useful info on tuning these carbs. and finally block off the secondary enrichment hole

at the top of the carb which apparently makes a big difference in more accurate fuel metering (see reference to carb in c.d.iesel article)

 

Gale H

 

 

[androvers]

Thank you, my setup seems way out of wack, and missing the secondary idle jet. Will look into this.

[zinz]

The jets and parts are readily available at Pierce Manifolds and other places... You will need the missing idle jet.

 

Ed

 

[avoirdupois]

 

As so many threads/posts on this subject will attest, there is no easy (exact) answer to your question.  Simeon's good advice allows for many obvious variables, most of which involve reduction of rolling and wind resistance and weight applied to the gas pedal.  Each engine tends to have slightly different needs and that includes ignition timing, valve lash and yes, even spark plugs and their gaps.  Each one of these variables can make or break the best carburetor set up.  An exhaust gas analyzer and/or dyno is probably the most scientific method to establish what carburetor settings work best for your engine and driving needs/style.  The next best advice is "when in doubt, lean it out."  If you have the time (and inclination) start with your decent baseline and proceed incrementally as lean as possible without sacrificing engine performance.  Read your spark plugs and exhaust pipe.  Experiment with ignition timing.  Your wallet, seat bottom and tailpipe will indicate your success rate.

 

Keep reading:

http://www.bayarea02.com/techtips/bmwfaq_2002.html#13.3.7

http://www.bayarea02.com/features/carburetor/index.html

 

 

 

Edited February 13, 2017 by avoirdupois

[androvers]

1 hour ago, zinz said:

The jets and parts are readily available at Pierce Manifolds and other places... You will need the missing idle jet.

 

Ed

 

 

Going to give Pierce Manifolds a call today, thank you!

[androvers]

36 minutes ago, avoirdupois said:

 

As so many threads/posts on this subject will attest, there is no easy (exact) answer to your question.  Simeon's good advice allows for many obvious variables, most of which involve reduction of rolling and wind resistance and weight applied to the gas pedal.  Each engine tends to have slightly different needs and that includes ignition timing, valve lash and yes, even spark plugs and their gaps.  Each one of these variables can make or break the best carburetor set up.  An exhaust gas analyzer and/or dyno is probably the most scientific method to establish what carburetor settings work best for your engine and driving needs/style.  The next best advice is "when in doubt, lean it out."  If you have the time (and inclination) start with your decent baseline and proceed incrementally as lean as possible without sacrificing engine performance.  Read your spark plugs and exhaust pipe.  Experiment with ignition timing.  Your wallet, seat bottom and tailpipe will indicate your success rate.

 

Keep reading:

http://www.bayarea02.com/techtips/bmwfaq_2002.html#13.3.7

http://www.bayarea02.com/features/carburetor/index.html

 

 

 

 

Thanks for the link and advice, I am going to start with C.D.'s baseline and order a pack of jets and emulsion tubes and tune it out.

[androvers]

What is everyone's favorite guide to tuning Webber Carburetors? Hopefully one that covers both the 32  / 36 and the 38. Thanks all, this site makes all of this doable. 

[Leitrum]

To be fair, secondary idle jet is only missing because I robbed it for the 38/38 that came on the car at sale.   32/36 was rebuilt when I got it so other than re-jetting, should be in fine shape as you saw. 

 

Also, if you want to pass emissions with ease, drop the 32/36 on and take it to Pacific Motorsports and get James to take care of it. It'll cost a bit extra (around 300 if I recall), but it's guaranteed no matter how many trips he has to take. you're going to have a hell of a time on your own unless you swap the cam, especially considering those pistons. 

 

Good luck! 

[APka]

This is a novice question, as I have only just ordered a book explaining Weber carburators, but either I am unable to find 36/38 DCOE carbs, or are you modifying DCOE 40's?

 

All I can see for purchase are DCOE 40 151 such as these : 

https://classiccarbs.co.uk/product/pair-of-weber-40dcoe-151-twin-carbs-mk1mk2-escortsierravw-golfalfa-romeo

[Simeon]

The carbs in question are a 32/36 DGxx or 38/38 DGxx the xx can be a few different combinations of letter depending upon the type of cold start choke it has. For example DGAV is a water/coolant temperature operated choke (A for aqua, Enis electrical). DGV is manual choke. 

[APka]

On 23/03/2017 at 1:54 AM, Simeon said:

The carbs in question are a 32/36 DGxx or 38/38 DGxx the xx can be a few different combinations of letter depending upon the type of cold start choke it has. For example DGAV is a water/coolant temperature operated choke (A for aqua, Enis electrical). DGV is manual choke. 

Thanks for the response, but what do the 32/36 indicate? The size of the carb?

[rstclark]

The size of the primary and secondary

the 33/36 is progressive and the 38/38 is not