What is the difference between single throat and dual throat Webbers as to keeping them tuned and synchronized? Not in detail but are the dual throat a lot harder to work on?
Thanks, Tom
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What is the difference between single throat and dual throat Webbers as to keeping them tuned and synchronized? Not in detail but are the dual throat a lot harder to work on?
Thanks, Tom
Thanks, Tom
In single carb applications, neither type is much of a problem...
The dual throat units are a bit more difficult to tune in dual carb instalations.....
Throtle linkage problems are about the same on single or dual throat carbs...The biggest problem is balancing air flow through all 4 throats,in dual, dual throat applications.
Jetting is slightly more work, in that Weber dual throats are basicly two single throat carbs sharing a single float bowl....Two air jets, two main jets, two pump jets, etc....
With a copy of Tomlinson's WEBER TECH MANUAL, just about anyone can tune Webers....
Good Luck...
Leon C.
The dual throat units are a bit more difficult to tune in dual carb instalations.....
Throtle linkage problems are about the same on single or dual throat carbs...The biggest problem is balancing air flow through all 4 throats,in dual, dual throat applications.
Jetting is slightly more work, in that Weber dual throats are basicly two single throat carbs sharing a single float bowl....Two air jets, two main jets, two pump jets, etc....
With a copy of Tomlinson's WEBER TECH MANUAL, just about anyone can tune Webers....
Good Luck...
Leon C.
I'm firmly convinced that putting webers on a car that didn't come with them from the factory is a hobby fully unto itself! I put them on a '72 914 with big bore pistons and reworked heads. I always had a stumble oof the line or a flat spot in accelleration -- and gas mileage went way down. Finally stopped buying jets and instead filled them with lead and drilled them out to size. There was still tracking down air leaks, proper fuel pressure and cloughed jets too. I wish I had tried the stock FI with the engine mods -- but was led to believe it wouldn't compensate (and those old computers were not really programable like new ones).
I beg to differ; dual throats run better and are actually easier to tune than single throats (at least the Kadrons I had).
Well, that's probably true for some of them.....
I had a pair of single throat Zeniths on an engine many years ago and they were a major PITA to keep them sync'd (although, in retrospect, maybe the El-Cheapo linkage I was using had some to do with that).
Switched over to Solex (now Kadron) duals (forever reaching for those few more horses without actually changing the heads - duh...) and they were easier to keep in sync (newer linkage probably helped) and didn't clog up much, but they were still enough work that I eventually went to a single Holley 2-barrel mounted on a conversion intake manifold that three of us built out of pieces of others.
Put the thing on, jetted it correctly and it just plain worked from that day on. Many others did the same conversion (I think EMPI even produced a good intake manifold for that, eventually).
Having said all that, I'm now running a pair of dual-throat Dellortos which I set up when I first got the car on the road (using Bob Tomlinson's Dellorto tuning book) and I honestly haven't done anything to them in two or three years, other than clearing one clogged idle jet in that time. I just got done re-balancing them as I just updated my CB linkage to Heim joint ends, and all I did was tweak one air by-pass screw, so they've held their tune for three years now.
gn
I had a pair of single throat Zeniths on an engine many years ago and they were a major PITA to keep them sync'd (although, in retrospect, maybe the El-Cheapo linkage I was using had some to do with that).
Switched over to Solex (now Kadron) duals (forever reaching for those few more horses without actually changing the heads - duh...) and they were easier to keep in sync (newer linkage probably helped) and didn't clog up much, but they were still enough work that I eventually went to a single Holley 2-barrel mounted on a conversion intake manifold that three of us built out of pieces of others.
Put the thing on, jetted it correctly and it just plain worked from that day on. Many others did the same conversion (I think EMPI even produced a good intake manifold for that, eventually).
Having said all that, I'm now running a pair of dual-throat Dellortos which I set up when I first got the car on the road (using Bob Tomlinson's Dellorto tuning book) and I honestly haven't done anything to them in two or three years, other than clearing one clogged idle jet in that time. I just got done re-balancing them as I just updated my CB linkage to Heim joint ends, and all I did was tweak one air by-pass screw, so they've held their tune for three years now.
gn