I had triple DCOEs (side drafts) on my TR-6 for a couple of years. In my
opinion, this is more of a racing
setup than a street setup. The DCOEs are tough to tune, and eventually
required rebuilding the engine
due to excesssive gasoline on the cylinder walls causing premature cylinder
wall wear (gas running down
cylinder wall strips the oil off and the resulting lack of lubrication
causes premature wear).
They were a blast while they lasted but I would never do it again.
Now, I've never run the dual DGV (downdrafts). But, here a couple of things
to think about. The triumph engine
should take the additional HP if it and your associated drive line are in
good shape. So I would tend to discount that
concern. However, no carb, weber or otherwise, wll perform correctly
unless tuned correctly.
(and the Weber's are not simple to tune like the ZS or SUs. ). If the carb
runs rich, you take the chance of getting too much gas
into the cylinder and causing premature cylinder wear. If it runs too lean,
you can burn up valves and/or overheat.
To me this is the key - tuning and the condition of the carb.
Something that has become popular in the last few years (not necessarily
with Triumph owners but with people who still have carbs)
is mounting an O2 sensor with Air Mixture Gauge. This will give you a
real-time indication of what your carbs are doing as you drive. Summit
sells a digital gauge for about $40 bucks that will do this (the O2 sensor
will run you about $35 from a local vendor).
This makes carb tuning significantly easier (IMHO) although you still need
to isolate which carb is causing the condition (rich/lean). But a little
trial and error will usually point you in the right direction. (Now if I
can only figure out how to make my 1969 ZS jets adjustable).
Dave Sterrett
69 TR-6
At 11:41 AM 6/25/99 -0400, you wrote:
>
>This came into the VTR web site. Anyone care to share their experience
>and/or expertise with Dane? My gut reaction is that no Weber -- DGV, DCOE,
>etc. -- or other carb replacement is THE answer in itself, but needs to be
>thought out wellas part of a "system" with freer-flowing exhaust and
>possibly much other work, etc., etc.
>
>--Andy
>
>* * * * * * * * * * * * * * * * * * * * * * *
>* Andrew Mace, President and *
>* 10/Herald/Vitesse (Sports 6) Consultant *
>* Vintage Triumph Register <www.vtr.org> *
>* amace@unix2.nysed.gov *
>* * * * * * * * * * * * * * * * * * * * * * *
>
>On Wed, 23 Jun 1999, Dane Connell wrote:
>
>> OK, set me straight.
>>
>> I have a '76 TR6 needing the ZS 175's rebuilt. I thought I would put the
>> money for a complete rebuild kit into a DGV setup from weber. Everything
>> I've read on the web indicates that this is a very popular aftermarket
>> setup, improved performance, etc. Certainly are a number of vendors
willing
>> to sell me this setup.
>>
>> I stopped by a well-known (20 years in existence) LBC service outfit and
>> asked how much the DGV setup would be through them. Thought I might help
>> pay for some bricks and mortar rather than buy EVERYTHING mail order....
>>
>> The response I got shocked me. Counter-man suggestd that he would not sell
>> the DGV for a TR6. Shared that when they take them off TR's, they throw
>> them in the trash. This is a big outfit too...
>>
>> He suggested that yes, people do sell them, but that alot of the TR6's
>> needing major engine-repairs have these webers on them and that they place
>> too much strain on the bearings, put too much gas in the crankcase, etc.
>>
>> SET ME STRAIGHT. Do I rebuild the ZS 175's and heed this gentleman's
>> advice... Is moving to the weber setup going to buy me problems down the
>> road? or is the DGV setup, as advertised, an easy upgrade with performance
>> benefits that makes alot of sense?
>>
>> Thanks for your time.
>>
>> Dane Connell
>>
>>
>> _______________________________________________________________
>> Get Free Email and Do More On The Web. Visit http://www.msn.com
>>
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