Now we are getting somewhere. As Ted and John say you can't beat a set of
SU's. I made the change on my 69 TR6 Many years ago and the car has never
run better. A lot of people comment how quiet my engine runs. If I wanted I
can idle this engine down to 450 RPM and doesn't miss a beat. I set it at
850 all the time. With the Su's you can get the mixture correct and can also
get more choices of needles if you run a header or different cam. Mine is a
single pipe early TR250 head with a stock cam. Drove it to Hudson, Wisconsin
from Richmond, Virginia and averaged 30.5 MPG with the OD.
Before putting on the SU's I tried a set of TR4 Strombergs with the
adjustable jet in the bottom. They worked good but I couldn't get needles
that gave me a good mixture thru the RPM range. They just aren't available
anymore. They would be OK at idle and high RPM but would stumble in the
middle. Part of the problem is the needles were profiled for the 4 cylinder
engine. Finally decided to "Put on a set of SU's and be done with it".
Dean Tetterton
Bought my first TR3 in 64 and still have it.....
Ted Schumacher wrote:
> john is correct. fit a pair of su's and be done if you look at the
> air/fuel path, you enter from the top, pass throught he carb and hit the
> bottom of the manifold. then a 90 degree turn in each direction to go
> fore/aft. then another 90 degree bend to dt tot he engine. by now the
> air/fuel mixture has forgotten its purpose. bolt on a set of hs6 su's.
> 1.75" throat with a direct path to the ports. ted
>
> "R. John Lye" wrote:
>
> > Hi Bill,
> > While your analysis of the down draught Webers on a
> > TR-6 makes sense in theory, the problem really lies in the
> > manifold (as you guessed). In my experience, the design
> > of the manifold adaptors is such that as the flow makes the
> > 90 degree turn, fuel tends to puddle out which leads to
> > driveability problems.
> > Maybe I've never seen an application that was set up
> > properly, but I've never seen these carbs work well on a
> > TR-6. I'd still stay away from them.
> >
> > Happy Thanksgiving,
> >
> > R. John Lye
> >
> > rjl6n@cstone.net
>
> --
> Ted Schumacher
> TS Imported Automotive
> 404 Basinger Rd.
> Pandora, Ohio, USA 45877
> Ph. 800/543-6648 USA/Canada FAX 419/384-3272 24 hour
> Ph. 419/384-3022 - tech./general information
> Web page http://www.tsimportedautomotive.com
> New-Used-Rebuilt-NOS-Performance British car parts.
> 200 - 300 parts cars in our British-only salvage yard.
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