Main jets??

They may, or may not be 135s. Lots of guys drill them.

As to the question- "2332" can mean anything from 94s and a 84 mm crank with stock heads and a set of Kadrons running into a Monza exhaust, up to the engine in Al's outlaw with Comp Eliminators, 48s, and 1-7/8" header.

Heads, cam, exhaust? How big are the carbs? Details?

How has it been running with the "135's"?

What color are the plug electrodes after running a while?

I know you don't have an air/fuel mixture gauge, so we can do this old school (like when you had your coupe).

If the plugs are grey or white, it's too lean.  If they're dark brown or black, it's too rich.  If they're light brown/tan, you're in the ballpark.

Also, it would be cool to know the size of the idle jets.

Just as a reference, I'm running 162's for mains with my Dell 40's, and as Stan said, you don't know the size of your jets without a jet reamer to use as a sizing tool.  (Oxy/acetylene torch drills can do the same thing and are more readily available).

OK folks, I'll spill a bit more.  I have gauged the jets, and they are damn close to 135.  Idles are 55, also gauged. Running 44 IDFs (thought EVERYBODY knew that). According to Mr JPS, this engine is of course 84x94, CB Alum pent roof case, clearanced for the extra throw,  Scat lifters, Engle 110 cam,  8 dowel lightened flywheel,  Mahle 94 pistons, CB 044 heads 40x35.5, single springs, Scat 1.1 rockers, Kennedy 1500 lb pressure plate.  

And some other stuff.  Plugs look about right, although almost everyone who has stood around my car w engine running thinks its running rich.  But they also say that's the idle circuit not tweaked right, not the mains,  When right, this engine pulls very strong and lights up my life, as well as whomever may be in the right seat.  When operating where the mains are the "main" player, it seems good to me.

Reading some old SOC posts w/ the search feature here, I see mains for 2 liter+ engines all over the place.  Most seem to say that if you are serious about this, you cut and try various combos until you find one you like.  Well, that is a whole lot of wrenching, and if you are truly serious, you get up on a dyno, hang on an O2 sensor.  And if you are totally insane, you pay an exorbitant fee to Jake Raby and have him dial the sucker in.

If you want a dyno tune, ask around at some of the engine guys that Cory knows in the area and see who has a rear-wheel dyno and what their fee-structure is.  Might not be too bad for them to do it - usually $200-$400 bucks.  Here in Mass. we have ACS Racing over in Hanover and they do that stuff for a living and LOVE aircooled engines. 

The tough part with your Webers is getting to the jets, plus you'll need a selection of Mains to play with, like 145 - 160's (at $4/each*4*5 sets = $80 for a bunch of jets you won't need once done finding the right ones).  

It's hard to judge air/fuel ratio for main jets when you're not on a track - Performance and plug color are your only insights but most of the time on the street you're on the idle jets.  I tested mine by running hard on an interstate then pulling right into a parking lot, cooling off a little and pulling the plugs to check color (real old-school, that!)  THAT was so much fun    that I ordered a CB Air/Fuel gauge which made the process a whole lot easier and more fool-proof.

So, you can buy a set of jets to try for $80 and not use $64 worth of them, or buy a Wide Band A/F meter for $300 delivered, use it for one day and set it on a shelf for a looooooong time, or you can take the car to a shop with a wide-band A/F meter, get them to dial you in so it's running right and never mess with it again for a price in between the two.

I apologize for not memorizing your carburetor specs, Kelly. I still don't see anything about the exhaust, but regardless-- with that mild of a cam, that engine would be a lot happier with 40s.

Anyhow, with a 110 cam, 1.1 rockers, and unported 044s (if they were ported, the card would have said so and had something about port-matching the manifolds as well), I'm guessing you are pretty close to correct as presently jetted. You might go one step fatter on the mains, but probably not.

Either way, somebody re-jetted them. That's not how they come from Weber, so somebody took the time to set them up as they saw best.

Gordon is right-- you can easily end up with hundreds of dollars in jets trying to get it just so, and without an 02 sensor in the exhaust, you are just guessing anyhow.

Not to let it out of the bag, but in the near future I will be able to offer Classic dyno services. From just running it to see the torque/hp numbers to tuning it. 

On Webers, in a Speedster, the idle jets are a pain in the ass. The mains, however, are screwed in the top just like your beloved Dell's. So how is that difficult exactly?

Kelly, don't fret. I think you're jetted just fine. BTW I never smelled anything bloody rich when behind you. And if it was lean, it would have burned up a long time ago.

Without O2 sensor and real time driving with someone to read it (or a dyno) is all just mental *********ion.

Cheers.

FYI, I have a wide band, but you need a bung in your exhaust or need fabricated tube to attach the sensor. Closest to where all 4 pipes come together is bestest.

Gordon Nichols posted:

If you want a dyno tune, ask around at some of the engine guys that Cory knows in the area and see who has a rear-wheel dyno and what their fee-structure is.  Might not be too bad for them to do it - usually $200-$400 bucks.  Here in Mass. we have ACS Racing over in Hanover and they do that stuff for a living and LOVE aircooled engines. 

The tough part with your Webers is getting to the jets, plus you'll need a selection of Mains to play with, like 145 - 160's (at $4/each*4*5 sets = $80 for a bunch of jets you won't need once done finding the right ones).  

It's hard to judge air/fuel ratio for main jets when you're not on a track - Performance and plug color are your only insights but most of the time on the street you're on the idle jets.  I tested mine by running hard on an interstate then pulling right into a parking lot, cooling off a little and pulling the plugs to check color (real old-school, that!)  THAT was so much fun    that I ordered a CB Air/Fuel gauge which made the process a whole lot easier and more fool-proof.

So, you can buy a set of jets to try for $80 and not use $64 worth of them, or buy a Wide Band A/F meter for $300 delivered, use it for one day and set it on a shelf for a looooooong time, or you can take the car to a shop with a wide-band A/F meter, get them to dial you in so it's running right and never mess with it again for a price in between the two.

Hello Gordon., what size engine are you running your Dells on? I run a 1915cc and I have dual Dell 40's and when I adjust the idle mixture screws in or out from the baseline 3.5 turns, there is not much of a difference noted. My dells use 145's for the main jets, 180 emulsion tubes, and idle jets are 60's. any suggestions for idle jet changes or ???? Thanks much.

Dutch

Dutch:

The engine is a 2,110 with 35.5 and 40 valves in 044 heads, CB's mid-size intake manifolds (match ported), an Engle 120 cam and a Berg extractor exhaust.

Jet Sizes:

The carbs are 40mm Dellorto DRLAs I got from CB back in the mid-1990's, but I installed the Horizontal Discharge tube kits before I ever used them – The horizontal tubes make more power. That's all that has been done to them, but the Horizontal tubes ask for different jetting that I’ve slowly been homing in on.  

These Dell carburetors came stock (mid-1990's) from CB with .60 idle jets, 140 Main jets, 180 air correction (Emulsion) jets and .35 accelerator pump jets. Using those gave a huge hesitation as it transitioned from idle to main jets – it was undriveable.

The current jet sizes are:

.65 idles (makes it a bit rich, like 13 on an A/F meter - I may be going to .60's)

1.625 mains (1.50 jets reamed to 1.625 with a jet reamer - gives 14.2 on an A/F meter)

160 air correctors (to slow down the fuel through the main jets to overcome the hesitation)

.55 Accelerator pump jets (pump stroke about mid-range right now)

and the new venturis from the horizontal tube kits.

 You might try going down to .55 Idle jets (maybe even .50's)  My air mixture screws are turned out around 3 turns (can't remember exactly how many turns) but when I go in 1 to 1-1/2 turns it starts to stumble until I come back out at least 1/2 turn and then I slowly go another 1/2 turn or so til it's smooth.  If I go out another turn or so it will begin stumbling again til I go back in.

If I develop a gasket leak between intake ports (I don't have a lot of metal between intake runners at the head - Maybe 1/8" between them) then the mixture screws don't have much effect.  But then, the engine idles roughly and gently pops a lot at idle, too, and the A/F meter shows it running lean.

Hope this helps.

Come to think of it, Dutch, what kind of fuel mileage are you getting, and do you know roughly what color your sparkplug electrodes are when you pull a plug?

Great info as always Gordon thanks. My CMC came with the Dells so I do not know when the last time was that they were gone through. I am looking at going to the Dell Kit with the horizontal spray bars as well, but then it sounds like it becomes a new jetting game like you said. I'll try changing to the .55 or .50 idle jet first to see if anything changes. I have not really monitored my mileage and will start doing that. When I pulled the plugs to replace them last time all were a nice tan color except cylinder 1 on which the electrode was a  gas smelling black so too rich running cylinder was my guess. I'll check the plugs again, change the jets then run it and check the plugs again. 

I will also check for any kind of manifold leaks to make sure that is not a contributing factor.  

Gordon I sent you a PM...