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Re: Side draft Weber on a 1500?

To: "Paul Shirley" <pshirley@micron.net>
Subject: Re: Side draft Weber on a 1500?
From: Ronnie Day <rday@cyberramp.net>
Date: Tue, 9 Mar 1999 20:36:55 -0600
>On a slightly different topic.  I spoke to my local parts house today
>and inquired about dual DCOE Webers for my 2L.  I didn't think there was
>a kit for the roadster.  He called me back and told me he could get
>everything, carbs (40s or 45s), manifold and linkage for $900.  Has
>anyone gone down this road before?  It sounds like the way to go, lots
>of parts available.  Any pros and cons are welcome.  thx Paul

Hi Paul,

Looks like you made it back home from Austin okay. Gordon has some pretty 
good info on Weber applications (I think) as well as a lot of other 
stuff, too. I do remember him mentioning something about the throttle 
plates rotating in the opposite direction than the Mikunis. If you're 
prepared to deal with it, probably not a major hurtle. I have a rather 
lengthy analysis by Marc Sayer comparing Webers and SU's. I think he also 
mentions the flow differences in the 40 and 45 DCOE's, too. I'll be happy 
to send it to you if you'd like. Usually, for a street or dual purpose 
car, the 40's are a better choice, actually outflowing 45's (with the 
same size chokes) at low and mid RPM.

The biggest trick with that type of carb (dual throat sidedrafts) is 
getting the right emulsion tube and getting in the ballpark with idle, 
pump, main, and air jets. These tend to vary with the different size 
auxiliary venturi (chokes) that you use. Even on a 2 liter, smaller is 
usually better for the street. Remember also the discussion when Daniel 
was considering Mikunis for his car. If you want to get appreciable gains 
from going this route, it needs to be part of a coordinated plan.

I'm really not anti-Weber, Solex or anti-dual throat. In the right 
setting they're great. In fact I'll almost certainly use 40 DCOE's on the 
E/P car. They aren't magic solutions by themselves, definitely when 
trying to use a single. Trust me, I found out the hard way.

FWIW, Ron

________________
Ronnie Day
rday@cyberramp.net
Dallas/Ft. Worth
'71 510 2-dr (Prepared class autocrosser)
'73 510 2-dr (Street Toy)


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