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RE: Need Weber tuning suggestions

To: "'Jack Wheeler'" <jwheeler@seidata.com>,
Subject: RE: Need Weber tuning suggestions
From: Peter D Vucinic <vucinic@b140.aone.net.au>
Date: Tue, 6 Jun 2000 19:49:15 +1000
Weber state (Weber tuning manual, Part No.9500005401, Page 53) that with a 
DCOE, inclining them up to 5 Degrees (NOT MORE) may prove useful. 

I have a set of MOSS UK Inlet manifolds and 45 DCOE's fitted to my TR4, and the 
angle of the manifolds is approximately 5 Degrees, to the horizontal.

I would suggest that other manufacturers of manifolds increase the angle of 
inclination to avoid interference of the carburetors with the inner guard. I 
know in my case that When I fitted the manifold/carburetor assembly to the 
engine, I could not fit the K&N style of paper element air cleaner assembly, as 
it interfered with the inner guard. I had to modify the inner guard some inches 
to allow the air cleaner to be fitted.

I know that some people put spacers under the engine mount on the carburetor 
side which, in effect raise the carburetors away from the inner guard. However, 
as far as I am concerned this defeats the purpose of having the 5 Degree 
inclined manifolds. Alternatively you may not want to run the paper element 
style of air cleaner with 5 Degree manifolds and elect to run with foam socks 
or similar. In this case the carburetors will not interfere with the inner 
guard, as long as you do not use an excessively long ram tube.

When manifolds are inclined excessively any unatomised fuel left in the inlet 
tract, will have a greater tendency to run into the cylinder head/valve area. 
In saying this, the primary objective of correct jetting is to achieve an 
optimum atomization / fuel mixture at all throttle openings and if you are 
experiencing excessive fuel flow at low RPM, the jetting should be revised. 
Problems with the achieving correct fuel bowl level settings may also be 
experienced with excessively inclined inlet manifolds / carburation.

Hope this helps.

Should you require pictures etc. of my set up, let me know as I would be happy 
to send. 

Regards 
Peter Vucinic
Australia
WORKS-TR4
vucinic@b140.aone.net.au


-----Original Message-----
From:   Jack Wheeler [SMTP:jwheeler@seidata.com]
Sent:   Tuesday, 6 June 2000 5:23 am
To:     'R. John Lye'; Carsten Conrads; Matthew Wilder
Cc:     fot@autox.team.net
Subject:        RE: Need Weber tuning suggestions

I have a set of 42DCOE's on my street TR-4.  I am using a Kastner 'D' can 
with about 10:1 compression.  The engine really screams at high RPM's, but 
tends to pop and sputter a bit when driving around town.

The manifold which came with these carbs has the carbs located at a 14 
degree angle up from horizontal.  I've been told by a friend that according 
to some of the manuals, Weber carbs should be mounted at no more than a 5 
degree angle up from horizontal.  In fact, my friend modified his manifold 
to get his carburetors down to exactly horizontal, and this seems to work 
well.

Does anyone have any experience with the mounting location of Weber carbs? 
 If the 5 degree recommendation is correct, then why do the kits all seem 
to come with a manifold which puts them up at 14 degrees?  Modifying the 
manifold can be a pretty major task.  By the way, my friend says that when 
mounted at too high an angle, fuel tends to drip into the manifold from the 
force of gravity (he calls it 'Post Nasal Drip').  At high engine speeds 
the extra fuel gets consumed, but at low RPM's the engine is overfueled.

I'd appreciate any thoughts or experience from the group.

-----Original Message-----
From:   R. John Lye [SMTP:rjl6n@server1.mail.virginia.edu]
Sent:   Monday, June 05, 2000 11:52 AM
To:     Carsten Conrads
Cc:     Matthew Wilder; fot@autox.team.net
Subject:        Re: Need Weber tuning suggestions

At 06:23 PM 6/5/00 +0200, Carsten Conrads wrote:
>The best are 45 DCOE, but 40 DCOE runs it also.

Actually, as I've been told, the 42DCOE's are even better (but they
have not been made for a while, so they are harder to find).

John Lye
rjl6n@Virginia.edu


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