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TR2/3/3A Weber Carb Installation Question

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M_Pied_Lourd

M_Pied_Lourd

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Hi All,

Playing around with installing some Weber DCOE 42's on my 1960 TR3A.

I have a question on what I should do about the vacuum advance line from the distributor since there is no provision for this on the webers.

Should I cap it and run without? Thoughts on timing adjustments, dizzy re-curving etc if required?

Thanks for the help in advance.

Cheers
Tush
 
That's pretty much the standard approach, just leave it off. No other changes to timing are required due to the lack of vacuum advance. It's mostly a fuel economy device anyway, and is only active at part throttle.

A friend of mine found a vacuum solenoid from another car, and wired it up to a microswitch controlled by the throttle linkage, so it only passed manifold vacuum to the advance when the throttle was open. He reported that it worked well, and picked a couple of mpg (about 10% lower fuel consumption).
 
IMO, if you are going to run primarily on the street, you should tap into the intake for the vacuum advance. I do like Randall's friend's solution. Tom
 
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Tush, I'm running 40's DCOE"s on my TR3a and I just sealed off the vacuum at the distributor and it has worked really good.
 
Thanks guys. I appreciate it.

Terry, will do as you have and seal off the vacuum at the distributor as you suggest and give it a try.

Cheers
Tush
 
One more quick question.

I think that I have read that I can get away with hooking up only 1 of the 2 cold start (choke) levers. Is that the case?

Cheers
Tush
 
Tush, when I first installed the carbs, that is what I did. I just hooked up the carb closest to the firewall. If the car sat for some time, I noticed it took more cranking to get it started using the choke; so I hooked up both of them and when I use the choke it takes right off. What I did was take a piece of brake line casing from a bicycle and cut it to fit between the carbs (keeps the choke cable straight) which works quite well.
 
Tush, here is a picture of my choke setup.
 

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Excellent, thanks again Terry. If you wouldn't mind, can you take or post a picture of your carbs looking at the filters. Looks like you have the same filters that my 250 has with triple 40 DCOEs . Do you know what length of velocity stack you have installed? I found that when I took the filters off my 250, the PO didn't run with any stacks. I understand that can be a big problem with DCOEs ....

Cheers
Tush
 
M_Pied_Lourd said:
Hi All,

Playing around with installing some Weber DCOE 42's on my 1960 TR3A.

I have a question on what I should do about the vacuum advance line from the distributor since there is no provision for this on the webers.

Should I cap it and run without? Thoughts on timing adjustments, dizzy re-curving etc if required?

Thanks for the help in advance.

Cheers
Tush
Click to expand...

I shifted to a mechanical advance distributor. I was amazed at the increase in power that the DCOE's brought! Very noticeable, and worth the effort. Jim
 
Tush, the velocity stacks I use are 3" long. I made the filters that you see on the stacks. The foam I used was too dense and it caused the carbs to run rich. Without the filters, the car runs great, but you run the risk of sucking dirt or something else in which could cause you some big problems. When I don't have the stacks on, I use a pair of K&N filters. Attached is a picture.
attachment.php
 

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Very nice! Thanks again Terry. Will post a pic of mine when I finally get them installed and running.

Cheers
Tush
 
Tush, speak to Frank Manning, who has the same carbs on his TR4. He may also be able to help with things like jet sizes, emulsion tubes and air correctors.
I think the 40 and 45 mm sizes are much more common as the 42s went out of production many years ago, but seem a good size for an engine with 86/87mm pistons. (Not sure what the capacity of your engine may be!)
See you at BCD I hope!
Simon.
 
Hey Simon, great suggestion. I will speak with Frank at BCD. I love his car. I have 87 mm Pistons in my car. Yes, the 42s are quite old...not sure if you remember Brian Mills from the OVTC. He used to run them on his TR4.

Hope to see you at BCD.

Cheers,
Tush
 
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