Need Help with tuning Webers

[01yelrt]

The exhaust valve- check ball sticks on my setup. The newer carbs (spanish built) come with a plastic ball in the exhaust valve which seems to get stuck and then the carbs go unpredictably from ideal mixture to very rich in a hurry. Does anyone have a solution for this problem?
The car "loads up" sometimes, not all the time by any means. I'm still working out the bugs on the system it runs perfectly 85% of the time. However... that leaves 15% bad.
PS, I do get some popping out of the exhaust frequently just off throttle. It seems to pop less after the car has been running for a while and it's fully up to temp. Still there is quite a bit of popping.

[427Aggie]

Your talking about the needle?

Matt

[01yelrt]

Yes the needle. I've ordered the old kind of needles from Pierce manifold which is supposed to be one without the ball. Is this going to make a difference? Thanks Aron

[Eljaro]

the main problem are those 37 chokes. They are sh.t on a 427. 40 or 42 are probably the best.Then you will be able to tune your engine without running it so rich. I ruined my rings with the setup mentioned often on this forum featuring 37mm chokes. Get a set of larger chokes or turn the ones you have to the larger size.
I did a LOT of tuning and trying and almost gave up on the webers, until I put in 40mm chockes. From there I got to this setup:
Main venturi 40mm
Third progression hole drilled
Idel jet 65
Idle screw 1 turn out
Idle holder 100
Main jet 150
Air Corrector 120
Emulsion tube very similar to F14
Pump bypass 00 (would bog down with a .50 when stepping on the gas suddenly).
believe me, the car runs like a champion. Incredible torque and instant response, reving up faster than the tach, so shifting when limiter kicks in at 6500.
And this is still not the end, I am still trying to get it to run even better. The pump bypass will probably have to go back in, but maybe a 20 or a 30( if I can find such a fine drill), because closed I shoots black smoke out of the exhaust when going on the gas.
And I am trying to get a set of 42mm chokes and even will try 45mm chokes, to see how it runs.
Inglese says in its technical primer:
Pull out those small chokes, drop in some large-diameter ones, which may be nothing more than thin-wall "sleeves", and you've got a set of 48 IDA's that will flow enough CFM to make a big block scream.
The 37mm chokes are for SB, for BB you need more air. Believe Inglese and believe me !

[ENTDOC]

right now I have the following on my 454cu FE. mains-65, Idle jets-60 with 120 holder; air corrector-205, by pass -50; 37 mm chokes` emulsion tube-F7

I still get a lot of black smoke on hitting the throttle so I am going to a 55 by pass. Still a stumble at 2400 or so but by and large the car runs very well. I will hook up the LM-1 AF tester soon to fine tune

I would like to try some 40 chokes at some point but mine is running well enough to stay with the webers and play with them over time, I enjoy it. found a guy in Italy that sells jets for 1.75 dollars so I ordered a bunch.

[Eljaro]

Entdoc,
who is the italian guy selling weber parts in Italy? Does he have a web page or email or phone?

I need 8 chokes 37mm or up. Anybody has any spare ones to sell ?????

[ENTDOC]

go the EBAY and type in weber jets, nice guy and prompt.

[CHANMADD]

I used to run a 2.0 Litre 4cyl Ford SOHC with twin weber sidedraughts with 38mm chokes. On a BB like said elsewhere you need air.Wish I had Webers on my car .Good luck.

[427Aggie]

The problem with bigger chokes is people don't like the stumble on the bypass from the idles to mains..as you go up in the chokes you get a much more pronounced progression stumble.

Matt

[Eljaro]

Matt,
I got over the stumble by using a 100 air corrector on the idle jet. You are effectively richening the upper idle. Then you lean the low end by going to something like an F14/F16 emulsion tube (leaner low end).

What the 37mm choke/F5-F7 emus.tube/60 air corr./ setup is doing now is overly richening the transition over a broad band to go over the stumble.You are effectively pouring gasoline all over to get one spot right.
With the richer idle but leaner low end emulsion tube you are pinpointing the stumble more precisely with less gasoline and more air from the 40mm chokes.
The F14/F16 tube helped a lot to smooth out the progression and probably the third progression hole (although I am not sure on this because I drilled it before going to the 40mm choke, and it did not help much).
No stumble whatsoever now.

You may like your 37mm choke setup and you are probably running rich.
If you go leaner with the jets the engine you will lose the smoother progression and it will not run well. So you have a compromise there.
Go to larger chokes on your BB and you will experience the real Weber fever !

[ENTDOC]

I really like the tuning threads and they show how it is possible to take different routes to get these things running well. When mine is tuned well I think I will try the bigger choke route to see how it goes. We should have a good consensous of jetting soon for us big block guys. I am going to put webers on my 302 GT40 soon,I do not expect as much difficulty with those.

[Full Throttle Al]

Here is the setup you need for your small block Weber project:



Alan Sorkey
Shreveport, LA
asorkey@hotmail.com

[ENTDOC]

nice setup Al, but I already have my small block webers sitting on the shelf

[G.R.]

Originally Posted by priobe

Thanks for the words of encourgement.
Its just that every time I try to post a problem about these webers, I never seem to get a response to my questions.

Here is a pretty simple question that I can not seem to find an answer to.....

I am experiencing a problem as well as others on CC, that when you start your motor with webers the fuel pressure starts to fade.

Anwsers
1. Is this normal
2. Is this a bad pressure gauge
3. Is it a bad fuel pump
4. Nobody seems to know the answer


what should the pressure be set too if it fades after the motor warms up. the cold setting or the warm setting. If you set it to the cold setting, how do you know if you are getting the correct pressure when it is warm? And vice versa.

Priobe,
I think the gauge pressure fade is more common than not. I've set mine with both the engine cold and warm I've found in my case that the warm engine setting, 3lbs, increases to about a 6lbs reading upon a cold start until the engine warms up and a rich mixture, lots of smoke out of the exhaust results and over time it drops to about 2lbs. I finally went back to a cold engine set of 3.5lbs and have left it at that, as long as I have fuel the engine runs well, the pressure will also show a drop to about 2-2.5lbs after being run for awhile. I'm using an Aeromotive 0-15lb "dry" gauge. I think if the fuel pump was bad you'd develop erratic pressure readings .

Gary

[priobe]

Thanks for the post Gary. I am going to exactly just that.... Set the pressure at cold to 3 psi and forget it. I already received the new Aeromotive pump so I guess I just tay with it.

[Mark Jackson]

anyone have a pattern of the mounting plate that bolts on the front and back carb for the bell crank and post. seen a pic of one in a factoryfive and need it for my 351w I'm runnin 48IDA's. mj

[traindriver]

Mark,

I have a laser cut plate like the one in the attached photo. It is for the bluethunder manifold. I positions a hole centered between the carbs for mounting a bellcrank. I had to make a min buy of 8 of them back when I did my IDAs. I'm looking for $40 for it.

Chuck

[Randy Rosenberg]

Originally Posted by ENTDOC

is it possible that you have a header leak that is giving you a false reading on the LM-1? I just orderd several sets of jets and got an LM-1 so I can try to get mine running better also...

LM-1's seem not to like being at the end of a sidepipe. I don't have one, but when a trusted expert tried to use one on my SPF, it didn't accurately at all. Others in our BACC have had the same problem, and they have installed O2 sensor plugs (ports) in their collectors in order to get the O2 sensor closer to the source and away from the end.

Hope this helps,
Randy R...

[Terry Brown]

I am the lucky recipient of one of Traindriver's laser cut plates. I had mine chromed and it simplified my linkage setup. Works much better than the side pull linkage. I think you are getting the DISCOUNTED price!! Better get it now before he raises the price!




Terry Brown SPF 930

[Gun Doc]

TrainDriver,

I know this is an old post, but was wondering if you still have any of those linkage plates? If not, where did you get them made? I have the side/end pull linkage and am thinking of changing it out for the center pull.

Gun Doc