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Posted by: bondo Jan 21 2007, 08:17 PM

Bear with me because it's been a while since I've done carb stuff and I don't remeber all the names of the bits.

I'm rebuilding a couple webers for markb, and he's going to use them on a 2 liter.

Here's what they have:

Venturis: 28
Thing above the venturis: 45
Idle jets: 45
Main jet assembly numbers starting from the top: 200, F11, 110
Accelerator pump jets: 50
Accelerator pump check valve: 55

I have another set of carbs to pull parts from that have the following:

Venturis: 28
Thing above the venturis: 45
Idle jets: 50
Main jet assembly numbers starting from the top: 200, F11, 115
Accelerator pump jets: 50
Accelerator pump check valve: 55

I realize there's not much different, but of what I've got, what will be the best starting point to minimize the amount of tuning later?

Posted by: Lawrence Jan 21 2007, 08:22 PM

For a 2.0/4 or a 2.0/6?

Posted by: bondo Jan 21 2007, 08:23 PM

Hehe, /4.

Posted by: Aaron Cox Jan 21 2007, 08:37 PM

32 vents...

125-140 mains depending on cam etc....
airs? - around 170-200
50 idles...
f11 emulsions

and the jet stacks you pulled F11 - emulsion, 200 is aircorrectopn, 110/115 main jet

Posted by: bondo Jan 21 2007, 08:58 PM

32 venturis! Yikes. Is that because a 2.0 really should have 44s instead of 40s?

Posted by: Twystd1 Jan 21 2007, 09:06 PM

Unless these 40s are for a VERY high performance 2.0

Your 40s are more than adequate.

C

Posted by: bondo Jan 21 2007, 09:09 PM

Ok, one more question... What's the correct float height setting? My weber book went to Hammy with the engine/webers I sold him.

Posted by: sww914 Jan 21 2007, 09:34 PM

Bondo, I can help you with the float height, it's easy. I drop off & pick up my son at the school across the street every day. Let me know and I can stop by.
Steve

Posted by: John Jan 21 2007, 09:35 PM

What else has been done to the engine?

In ours, many moons ago, we ran 40's, because that is what people at the time recommended. In retrospect, 44's would have been a better choice.

The 28mm chokes were stock with our 40's. We bought 32mm chokes and it was better. We had the 28mm chokes opened up to about 34mm at a machine shop and it ran even better (the best it ever did).

I believe:

F11 emulsion tubes
180 air corrector jets
135 main jets
50 idle jets

The engine was:
2.0 Euro Pistons
Rebuilt stockish heads (new seats, guides, valves, springs, retainers)
WebCam (don't know the grind, but it was what "everyone" recommended 20 years ago).
4 - 2 - 1 header, with stub pipes (make unknown but could be looked up) with a Phase 9 muffler.

For a street engine the 28mm chokes should be fine, I would work to get the idle jets dialed in well. On a street engine, most of your driving will be at part throttle and that will be depending on the idle circuits.

just my $0.02

Posted by: Twystd1 Jan 21 2007, 09:36 PM

(edited post)

There is a standard float adjustment that works for base line adjusting.

Go to REDLINE or CB performance and look it up.

In truth... The float adjustment can be used to help change transition and main fuel flow.

If you adjust it a bit high.. the emulsion tube/main jets get less aeration of the fuel and more pure fuel. Higher bowl settings... the opposite happens.

Just in case ya wanted to know...

C

Posted by: Aaron Cox Jan 21 2007, 09:38 PM

10 or 12mm depending on book for float height...

32's are for a base 2.0
i run 34's in my hot cammer'd one...

2056's are the toss up between 32's and 34's...

Posted by: Aaron Cox Jan 21 2007, 09:39 PM

isnt that backwards?

less fuel in bowl... less fuel thru the emulsion tube..more airation

check your email dude.

Posted by: John Jan 21 2007, 09:40 PM

The float should be 10mm in the full position, and should have 22.5mm travel (32.5 mm empty).

This distance is measured from the top cover without gasket in place.

I could scan something if you want to see it.

Posted by: r_towle Jan 21 2007, 09:41 PM

Hi,
buy your parts from aircooled.net.
They will swap parts with you till the motor runs perfect.

If the vents are to big, it runs to rich, so read the plugs.

Rich

Posted by: Aaron Cox Jan 21 2007, 09:47 PM

vents have more to do with intake velocity no?

you can go to smaller jets even with bigger vents

Posted by: r_towle Jan 21 2007, 09:51 PM

my experience was that larger vents made the car run richer...dont know why, it just did...

I kept all the rest the same, and kept stepping DOWN in vents till the plugs were perfect......again, no idea why...

Rich

Posted by: Twystd1 Jan 21 2007, 09:53 PM

AA.... U B right....

I wrote it backassward.......

Such is the beauty of senility.
I forget that I know what I don't know even when I know it.

Oh.. Man... I need some coffee and viagra.....

I mean aspirin....

I'll go back and edit the post so I don't screw somebody up...

C

Posted by: Aaron Cox Jan 21 2007, 09:58 PM

think of a river... a restriction (smaller venT) makes it flow faster....
a wider river flows slower....

so now begging the question (and thinking you are mistaken at the same time) doesnt more air velocity rushing by= more fuel sucked in an atomized?

Posted by: r_towle Jan 21 2007, 10:01 PM

again...no idea why it worked.

I was reading, learning, all the same stuff.
I had changed all the jets, no good.

When I changed the vents, to smaller...it did not run as rich...go figure...but it worked.
I was on the phone with the aircooled guys 30 min after each set of parts came up...till we tuned in on the venturis...
Baffled me...but when I got it,,,I was happy..

Rich

Posted by: Aaron Cox Jan 21 2007, 10:04 PM

groovy

Posted by: bondo Jan 22 2007, 03:32 AM

I know how to do it, I just needed the numbers (which I've now gotten from this thread). You're welcome to stop by and say howdy though, I'm going to be working out in the garage most of tomorrow (Monday) until 5:00 or so.

As far as final tuning goes... I don't have the engine, so I can't tune it. I'm just rebuilding the carbs so they'll be ready to tune. I just wanted to get it as close as possible with the parts I have.

Thanks all for the help!