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Help! Weber 40DCOE throttle problems Up-date

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Re: Help! Weber 40DCOE throttle problems Update

The last set of webers I tunes was on a Ford Sierra 2.0. I started with suggested settings and used a 12Volt CO meter and did a whole lot of driving and adjusting. Instead of buying all new jets, or borrowing a set of jets, I used my trusty jet drills. You can buy them in most stores. They're called number drills from #61 to #80 and are almost microscopic to see. If I drilled a jet out too much, I would solder it closed again and drill it a bit smaller.
This is really the backyard way of doing this job, but in the end it worked extreemly well. The car made it up to 190 kmh, and the idle was smooth, and the throttle response was excellent.
 
Re: Help! Weber 40DCOE throttle problems Update

Thanks for the suggestion will look those up.
 
Re: Help! Weber 40DCOE throttle problems Update

You'll want a GOOD pin vice, too, Dan.
 
Re: Help! Weber 40DCOE throttle problems Update

Ok here is what I did, the dicharge pump valve is located on the inside bottom of the DCOE fuel bowl. The one I have is a 50, or .5mm hole on the side of it, the before picture. I used JB weld to plug it and let it set 24hrs, after picture. We shall see if this corrects the problem.

PumpDischarge.jpg


The weber tech told me the hole should be pluged for MG engines. Which allows for maximum delivery of gas during rapid throttle movment.
I will post the results tonight once I install the "Plugged" valve and test run her.

I'm so excited!!!! God I hope this works!
Come on 4:15!!!!
 
Re: Help! Weber 40DCOE throttle problems Update

I'm going to be listening down here in Niceville.
 
Re: Help! Weber 40DCOE throttle problems Update

Might want to put in ear plugs /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
 
Re: Help! Weber 40DCOE throttle problems Update

YEAH!!!!!!! Ok now it bogs slightly and then catches up, I suppose this is the hesitation thing people talk about. But its 100 times better, does not bog and die. Only bogs then goes!! Yipppeeeeeeeeee

Will buy the #61-80 drill bits and start playing with the jets.

Thanks to all!
 
Re: Help! Weber 40DCOE throttle problems Update

WAIT, Dan!! Try just swapping out the F2 e-tubes for the F11's before ya get all drill-happy. /bcforum/images/%%GRAEMLIN_URL%%/laugh.gif
 
Re: Help! Weber 40DCOE throttle problems Update

Good Job and Congrats,
A short writeup in the wiki made help someone else later.
 
Re: Help! Weber 40DCOE throttle problems Update

Acutally I have F16's emusion tube in here now but this weekend I am doing a complete teardown and rebuild with the kit I got in. All new gaskets etc.... and will be trying the stock jets, emulsion tubes and venturi round robin thing to find the best tune for her, before attempting to drill anything. /bcforum/images/%%GRAEMLIN_URL%%/grin.gif

Will post results.
 
Re: Help! Weber 40DCOE throttle problems Update

/bcforum/images/%%GRAEMLIN_URL%%/thumbsup.gif
 
Re: Help! Weber 40DCOE throttle problems Update

FYI
For an A motor
Road setting. Weber 40DCOE
30mm Choke
120 Main Jet
45 Aux Vent
F16 Emulsion Tube
155 Air Jet
35 Pump
40F8 Idler Jet
This is what is fitted to Andrew's 1275 car so we know it works. It pulls as well if not better from all speeds. Significantly better than the standard twin SUs, especially on low-speed pickup. Sounds good too!

Fast Road setting. Weber 40DCOE
32mm Choke
145 Main Jet
45 Aux Vent
F16 Emulsion Tube
180 Air Jet
40/45 Pump
50F8 Idler Jet
This I have no direct experience of, but I would guess loses some low revs tractability. You'll need a hotter cam and/or high lift rockers to exploit the difference, otherwise I doubt it will do any more than the Road setting except burn fuel.

Race setting Weber 45DCOE
40mm Choke
190 Main Jet
45 Aux Vent
F2 Emulsion Tube
170 Air Jet
60 Pump
50F6 Idler Jet
This is xxx recommendation and will, of course be a starting point as any race engine will have to be sorted out on a rolling road to optimise it for all the other variables in cam, ignition, exhaust etc.
 
Re: Help! Weber 40DCOE throttle problems Update

Excellent, this is the information I have been looking for, someone that has a know working setting!! Super thank you VERY much!
Ɛan
 
Re: Help! Weber 40DCOE throttle problems Update

Finally checked mine:

Its' a 40DCOE 32 so the chokes should be 32 mm

137 Main Jet
?? Aux Vent
F16 Emulsion Tube
175 Air Jet
35 discharge jet size
50F8 Idler Jet
 
Re: Help! Weber 40DCOE throttle problems Update

Well after doing the round robin with the emulsion tubes, jets and veturis, it runs the best with the following:

30 = choke size
4.5 = auxiliary
125 = main jet
170 = air corrector jet
50/F9 = idle jet Change
F16 = emulsion tubes
40 = accelerator pump jet
Plugged = accelerator pump discharge

I ordered a 120 main jet, 155 air correction jet, 40/F8 idler jets, and a 35 accelerator pump jet.

The most notible changes in all of this was the F16 emulsion tubes and plugging the hole on the side of the discharge pump valve.

Well when the new parts come in I will give you guys an update!
Thanks!
Ɛan
 
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