Weber 44 running rich Options

[Dave97]

2270 with Weber 44 is running rich
50 idle. 1 1/4 screw out
Had 55. Drives better, but the a/f stayed about the same
135 main
175 air
Floats set at 9 with gasket
Have wideband sensor
11.0 at idle
Light throttle might see 12.8
Decel 13.2
Full throttle 13.7
Is there a air by pass circuit? It's almost the opposite of a air leak
Thanks for your help

[porschetub]

2270 with Weber 44 is running rich
50 idle. 1 1/4 screw out
Had 55. Drives better, but the a/f stayed about the same
135 main
175 air
Floats set at 9 with gasket
Have wideband sensor
11.0 at idle
Light throttle might see 12.8
Decel 13.2
Full throttle 13.7
Is there a air by pass circuit? It's almost the opposite of a air leak
Thanks for your help

Big carbs,what size venturies do you have? if too large you have poor vacuum signal and lots of hassles tuning,small venturies supply great low end power with a small power loss @ high end RPM which you only use for a very short time anyway.
A very common issue on here with carbs,SO many folks go big and think its better,on a T4 it won't really work due to valve and head port size unless you spend $$$ on trick...even that has limit.

[IronHillRestorations]

You don't say what size venturi. It's not generally recommended, but you could open all the the air by pass screws a half a turn, and see what happens. You could also try going up on air correctors, I'd probably try 200 and see.

[Dave97]

Bought the car with them. I think 36. Wouldn't smaller vents mean more vacuum? I agree for everyday driving smaller carbs would probably be better. Is there some sort of air circuit that could b e plugged? Both needles and seats leaking? It has 2 lbs fuel pressure. Thanks for the ideas

[Elliot Cannon]

My engine is just a bit smaller than yours. 76 crank and 96 P&C. 44idf.
I use 130 main
175 air
55 idle
32 venturis

I believe my floats are set a 10 without the gasket. I would try a smaller venturi. It's easy to change. My car still doesn't come off idle as smooth as I would like but I'm just too lazy to experiment around with the idle jets.

[Dave97]

And cylinder head temp light throttle is 200 with a max of 300 up a grade at 75mph

[Elliot Cannon]

Mine runs at 325 at 75 mph. 350 or more up hill, any hotter than that and I'll down shift to 4th and it cools off. 200 degrees (kinda low IMHO) sounds like a sender/indicator problem.

[Dave97]

Mine runs at 325 at 75 mph. 350 or more up hill, any hotter than that and I'll down shift to 4th and it cools off. 200 degrees (kinda low IMHO) sounds like a sender/indicator problem.

Any idea what your a/f ratio is? My guess is yours is in the middle 13's. Mine are in the 11's

[Gatornapper]

I have no business replying as I am rebuilding my Weber 44's now and my car has yet to run - BUT, all the research I've read says float setting is 10.5-11.5mm WITH the gasket on, set with top section held vertically on bench.

And in fully dropped position set at 32mm........

Seems to me that floats at 9 would be running rich.......

But then I have no experience with Weber's yet and am just learning.....

GN

2270 with Weber 44 is running rich
50 idle. 1 1/4 screw out
Had 55. Drives better, but the a/f stayed about the same
135 main
175 air
Floats set at 9 with gasket
Have wideband sensor
11.0 at idle
Light throttle might see 12.8
Decel 13.2
Full throttle 13.7
Is there a air by pass circuit? It's almost the opposite of a air leak
Thanks for your help

[Elliot Cannon]

Mine runs at 325 at 75 mph. 350 or more up hill, any hotter than that and I'll down shift to 4th and it cools off. 200 degrees (kinda low IMHO) sounds like a sender/indicator problem.

Any idea what your a/f ratio is? My guess is yours is in the middle 13's. Mine are in the 11's

I haven't got a clue. Although you just gave me a good guess. (IMG:style_emoticons/default/biggrin.gif) I've got to check that one of these days real soon. Some day. Maybe. Probably. (IMG:style_emoticons/default/laugh.gif)

[McMark]

Do you know what cam is in there? Lots of over lap can reduce your ability to accurately tune idle mixture.

Your full throttle mixture is too lean as well. Should be around 12.

[McMark]

Hi Mark. All thru the rev range it is in the 11's. on level ground 4th gear 2400 rpm light throttle might see 12.5. Most driving under 3000 is in the 11's. full throttle at 5000 I'll see 13.2. Head temp most of the time is 200 Thank for your help. Is there a air bypass? It's almost the reverse of a air leak. Dave

I think you have a lot of different issues going on. This is pretty normal for carbs, mostly because people underestimate carb setup and tuning (IMHO). Here's an overview of what needs to be perfected before you start evaluating the carb setup. These need to be done in order.

If you skip, or don't understand any of these steps, you may end up wasting time chasing your tail. Take the time to ensure all of these are 100% correct. And ask for help/clarification on any of the steps. Being thorough here will ensure you have the best running carbs you can.

1. Check compression
2. Check for cold start valves - SOME Weber IDF style carbs have a lever system on the side that allows for extra fuel to be added. Even if your carbs don't have the lever installed, they MAY still have the plunger valves and those can stick or leak. If you're not sure on this, you must post pictures of your carbs so we can see for you.
3. Adjust valves - Make sure you know if you have stock pushrods, hydraulic lifters, or ChroMoly pushrods. Each have a different setting, and any of the three setups could be in you motor if you don't know the history.
4. Set ignition timing - Make sure points/condenser (or Pertonix), spark plug wires, cap, rotor, spark plugs are all in good condition.
5. Check float heights - This can be tricky, make sure that you're doing this correctly. Don't compress the ball spring while checking. Ideally double check the fuel level with the carbs assembled and the fuel pump running, by removing the main jet stack and looking into the hole. Measuring that way is more challenging, but more accurate.
6. Make sure you have the correct linkage - If you have a hex- or cross-bar linkage, get the CSP Bellcrank linkage before moving any farther.
7. Sync the carbs - Make sure to check airflow at idle AND off idle. Make sure your linkage reads equal airflows at two throttle positions, closed (idle) and slightly open (off-idle).
8. Check for fuel intrusion - Look down the carb throats while it's idling. There shouldn't be fuel droplets dripping onto the closed throttle plates. Occasional drips aren't uncommon (1 drip per minute or less). But regular drips or 'excessive' wetness on the closed throttle plate is a symptom of an issue.
9. Tune idle mixture - Use the mixture screws to adjust idle mixture. Most engines like to idle in the 12.5 AFR range.
10. Check driving mixtures - When checking these mixtures, try to maintain constant throttle position. Also pay attention to how the car performs with quick, snap throttle changes compared to slow even throttle opening. Varying the throttle position too much will engage the squirters and add extra fuel -- this complicates your tuning because you're constantly changing the amount of fuel and 'masking' the fuel coming from the jets.

A couple potentially helpful videos from my collection:

Here's an engine setup video I made a few weeks ago. The part about carb setup is obviously why I'm linking it here.

https://www.youtube.com/watch?v=ZS3oNSwkUPk


And here's a video of what's happening in the carb throat while driving. This gives you a bit of perspective of what an idling carbs looks like (no wetness, drips) and also what I'm talking about with throttle position changes and accel squirters.

https://www.youtube.com/watch?v=XYDmTkNTk3w

[Dave97]

Thanks. I got 13.1 a/f but with the idle mix screws at 1/2. I ordered smaller idle jets. Not sure if I still don't have some diet in the idle circuit. This weekends project. Thanks for everyone s help

[Gatornapper]

I read about 36 venturi's and 32 venturi's - how come I never hear about 34 venturi's?

Anyone run those on 44's? Results? Seems like should be the best of all on this carb....

GN

My engine is just a bit smaller than yours. 76 crank and 96 P&C. 44idf.
I use 130 main
175 air
55 idle
32 venturis

I believe my floats are set a 10 without the gasket. I would try a smaller venturi. It's easy to change. My car still doesn't come off idle as smooth as I would like but I'm just too lazy to experiment around with the idle jets.

[Elliot Cannon]

Venturis and jets are relatively inexpensive items. I kept experimenting until I found a combination that works well for me. Type IV's have different cams, displacement, combustion, bore and stroke etc. Try a combination of jets and venturi's that work for you.

[Gatornapper]

Know that well from years of fiddling with carbs. Thanks.

I should have been more specific: for a totally stock 2.0 engine, what carb/venturi/jet combination seems to work best......? Hoping there were those who knew what works best with everything else being stock.

Of course, I know there will still be widely varying opinions - such is life. Just wondering if there is a consensus.....for a stock 2.0......

GN

Venturis and jets are relatively inexpensive items. I kept experimenting until I found a combination that works well for me. Type IV's have different cams, displacement, combustion, bore and stroke etc. Try a combination of jets and venturi's that work for you.

[porschetub]

Sir Andy and Elliot supplied the magic answer ,the carbs are too big ,the only way to restore vacuum is to run smaller vents....period,you can piss around all you like but you will NEVER achieve good drivability ,economy and tuning with 36mm ones.
There are lots of jetting charts and formula's that prove this fact...nothing has changed ,fit the correct venturies (32mm) and then work with idles and mains to suit,start with 55 idles and 130 mains and work up,don't play with everything @ once otherwise you will never achieve a baseline to work off.
If you don't do this you will be (IMG:style_emoticons/default/sheeplove.gif) and you will want to (IMG:style_emoticons/default/headbang.gif) (IMG:style_emoticons/default/headbang.gif) (IMG:style_emoticons/default/headbang.gif) and walk away.

[Gatornapper]

PRECISELY what I was looking for. Have the 32 venturi's in hand, need to get the jets.....and I know well from experience you don't make multiple changes at one time - if you do, you are totally screwed on knowing what the resultant change is caused by.

Just got my Weber Tech Manual and will be digging into it soon....

Thanks a ton!

Forgive me in advance - but I never stop with the questions: With stock engine, 32's, 55's and 130 mains - anyone have the typical settings for the Mixture screw and the air adjusting screw? Just be nice to get them close before doing running engine adjustments........

GN

Sir Andy and Elliot supplied the magic answer ,the carbs are too big ,the only way to restore vacuum is to run smaller vents....period,you can piss around all you like but you will NEVER achieve good drivability ,economy and tuning with 36mm ones.
There are lots of jetting charts and formula's that prove this fact...nothing has changed ,fit the correct venturies (32mm) and then work with idles and mains to suit,start with 55 idles and 130 mains and work up,don't play with everything @ once otherwise you will never achieve a baseline to work off.
If you don't do this you will be (IMG:style_emoticons/default/sheeplove.gif) and you will want to (IMG:style_emoticons/default/headbang.gif) (IMG:style_emoticons/default/headbang.gif) (IMG:style_emoticons/default/headbang.gif) and walk away.

[rhodyguy]

Just perform the pre-install procedure detailed in the Weber manual. Did you buy the Tomlinson version?

[IronHillRestorations]

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