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There are Webers and then there are DGVs

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billspohn

billspohn

Jedi Knight
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I am a former Triumph owner that drops by here once in ahwile out of nostalgia (I spend time on the MG board).

I was suprised to see people sticking those horrid DGVs on their Triumphs.

I spend time on the MG board explaining over and over that just because a carb carries the Weber name doesn't mean it is a high performance model, nd that while replacing a single smogged Stromberg on a late MGB might show some improvement, the best set up by far is still twin SUs.

Then I pop in here and see people sticking these downdraft contraptions on their Triumph engines. Why?

There is some argument for tossing the sometimes fussy 175 CDSE Strombergs on the later 4 and 6 cylinders in favour of the earlier 175 CDs, or a pair of HS6 SUs, but what possible reason could one have for inflicting a single (or dual) downdraft Weber on these engines?

It reminds me of the Spike TV rebuild show where two teams 'improve' the same model of car and then have a race. They once did the Datsun 260Z and the first thing they did was rip off the effective Hitachis and install a downdraft 390 Holley 4 bbl!

That was clearly ignorance - they only knew American cars and parts. But what possible reason can TR guys have for making similar mistakes. Is it the racing cachet of the name Weber that gives you bragging rights?

We used to rework TRs all the time, and it was by modifying the original carbs, or if the engine mods were significant enough to warrant it, we fitted either a pair of HS8 SUs, or wen the sidedraft Weber route (45 on the TR-4, usually 40 on the TR-6)

I'm not aiming this as criticism at any particular owner, but I was really wondering why the SUs (or Strombergs) were being tossed in favour of the inferior Webers rather than just doing a proper rebuild on the worn out original carbs. Especially when the DGV kits costs more than a pair of brand new bolt on HS6 SUs from Moss, so it can't be money....

PS - when I mention the DGV in the header I mean all of the versions of the downdraft 2 bbl.
 
Just about everyone in the local Triumph club that have installed those DGV's have ripped them back off. I think we still have one stubborn holdout. They've caused nothing but trouble to everyone that I have seen install them. :wall:

The SU's on the four cylinder TR's are capable of handling a large horsepower increase. On the six cylinder engines that are modified, the money would be best spent on the triple Stromberg or SU set-up.
 
BS!
I have had mine on my car for the past 3 years with out even one problem!
They perform as well as any SU, or stromberg tuned correctly.
When I decieded to put mine on, I had them completely rebuilt and rejetted.
They have electric chokes on them so no fuss with and choke cable.

People have the right to put anything they want on these cars, so making a statement like yours only means that you have had bad experiences with webbers.
I can make the same statement about Strombergs & watch the sh*t fly!

Many many people over the years have put these carbs on lbc's
theres a reson for that (They Work)
 
Billspohn, you make it sound like the majority of us Triumph owners prefer and recommend the DGV when that just isn't so. Some owners like Kodanja have them and like them but I think you'll find the majority of Triumph owners still stay away from DGV's. That was a pretty hasty generalization on your part.

Besides, on Triumphs, I don't think the DGV carburettor is the problem with the set up but its the manifold. After all, the DGV was used on several cars with sporting pedigrees from the factory without issue. The manifold used to put DGV's on TR's or Datsun's seem to allow fuel puddling which can wash down the cylinders on start up.
 
What Kodanja said... :iagree:

Why, you ask? The CD150 (later 1500) is a brutally bad carb, installed at the factory in the name of MPG and low emissions. The water choke would be more at home in a torture chamber.

- I got a barely-used DGV and manifold for a couple hundred bucks.
- Very easy install.
- Once installed, immediately better idle than the CD150.
- Electric choke, no muss, no fuss.
- Good mileage.
- Significant power increase over CD150.
- Great sound.
- Easy to tune.

Enough reasons for you?

No, it's not at the same level as a pair of DCOEs. But then, I don't drive a race car, and I didn't have to remortgage the house to buy it.
 
I see this reasoning behind DGV's quite a bit. So you replace a carburettor that was most likely in need of a rebuild with one that was practically new. How could you not expect better performance? Rebuilding the original carb and replacing the auto choke with a manual one if you were so inclined would have resulted in proper tune and running also.
 
Actually, I replaced a fully, professionally rebuilt CD150, with a used DGV that I rebuilt at home.

And, deleting the water choke and buying a manual choke for the CD150 would have been more work, and almost as much money as putting on the entire DGV setup.
 
If the Weber DGV is so bad, why does Pegasus Racing still sell lots of them for racing? Properly set up, they are a reasonable alternative to ZS or SU carbs on a Triumph. Basically set em and forget em.
 
Back to the OP... I think most of us agree that a dual SU setup would be nice. But DGVs, set up correctly, are simple, cheap and competitive. Anyone visiting Ottawa who would like a first-hand demonstration of how nicely a DGV can perk up a (mostly) stock 1500 is more than welcome to drop me a line.
 
I had dual ZS's on my TR7 FHC, went to the Dual DGV set up and didn't like the throttle response around corners (dead spots at various rpm's) and settled on dual SU HS6's. Less fuss and I got a more useable power band. So I've tried all three and settled on the HS6's. I sold my DGV's for what I paid for them and gave away the ZS's to another forum member.
 
Geez. Touchy subject, apparently.

The DGV Weber "family" have accelerator pump jets. Demand (or depression if ya prefer) don't. I'd like to see some empirical performance numbers from the same engine with both setups (done correctly, of course) as a comparator. I'm bettin' the initial "squirt" is afoolin' th' seat feel in some cases.

Those Cannon manifolds really are funky, BTW. Pools fuel directly under th' carb... premature piston/bore wear, hard starting when hot... yuck.
 
Hmm. I'd like to offer to strap the Z-S back on and do a dyno test... but when I finally got it off, I took a hammer to it, before throwing it directly in the trash. (Good therapy, after it caused one breakdown too many.)
 
At the risk of offending some, I wasn't really aiming this at the Spit 1500 owners. That is....well, let's just say it isn't my favourite engine whether in Midgets or Spitfires. I suppose that a DGV is a step up for them, as it can be for a single carb late MGB.

The people I was really referring to were the TR-2 through 6 crowd.

swift6, nowhere in my post did I say that I thought a "majority of us Triumph owners prefer and recommend the DGV". That just isn't there and I wonder why you are reading that into my post?


To those who got really cheap deals on DGVs. OK, I can see why YOU might have bought them, but for those who paid retail for new ones (fess up - if no one did that there wouldn't be any used ones around) why did you do that instead of replacing with SUs?

I've run 4 cylinder big Triumphs with SUs, erly Strombergs and smogged Strombergs and either of the first two are far superior to those DGVs.

Seems to me that paying MORE money for LESS carb makes no sense - unless you buy into the Weber name mystique and delude yourself into believing they are a performance model.

I have no doubt that the engines will run decently on them once they are set up properly (which takes some doing, sometimes) but they won't work as well as SUs do, especialy given the rather ill-designed manifolds they come with.

MGB owners go to the DGV when they replace the Stromberg because there is very tight clearance to the brake servo. The smarter ones are trying the Weber single barrel motorcycle carb, the MCHH and it seems to be better than the DGV. The really smart ones just source and earlier set of manifolds (you have to change the exhaust on them as well) and carbs. They now iffer MCHH kits for the six cylinder Triumph and while I haven't seen any test results I'm quite prepared to believe they are a good alternative.

PS - I think I have a set of 45 DCOE on TR4 intakes I should get around to selling if anyone wants to use a whole LOT of gas....
 
At one time or another, I had all three types on a spit 1500 I had owned. The car came with the single Stromberg. Performance, was shall we say "lackluster" I sourced a used DGV with a Cannon manifold, I rebuilt the DGV and installed it on the Spit. Performance increased considerably and it was quite easy to tune. All in all a much better carb than the Stromberg. After about a year I came across a set of HS4's and manifold which i then installed on the Spit. Again, performance and driveability was much improved over the Webber and even though the carbs did require a bit of extra "tweaking", in my experience, it was the best set up of the three.
 
My TR4 is early without ANY smog equipment. For an apples to apples comparison of rebuilt carbs without smog components, what are peoples opinions on which is better, twin SUs or twin CD175s?
 
SU's, hands-down. Less complex, no rubber diaphragm. MUCH more reliable.
 
I haven't had any ZS issues yet (now I'm jinxed), so rather than looking at it re. reliability, what about driveability? Engine response, economy, idling, whatever?
 
heliguy said:
At one time or another, I had all three types on a spit 1500 I had owned. The car came with the single Stromberg. Performance, was shall we say "lackluster" I sourced a used DGV with a Cannon manifold, I rebuilt the DGV and installed it on the Spit. Performance increased considerably and it was quite easy to tune. All in all a much better carb than the Stromberg. After about a year I came across a set of HS4's and manifold which i then installed on the Spit. Again, performance and driveability was much improved over the Webber and even though the carbs did require a bit of extra "tweaking", in my experience, it was the best set up of the three.
Click to expand...

That is similar to the late MGB experience. The DGV is probably a step up from the single Stromberg, but a pair of SUs beats the heck out of either. Some if those guys are using the Weber MCHH successfully - wonder if it would work well on the 1500?

Ian - although I am at heart an SU guy, I have nothing at all against the original non-smog 175 CDS carbs. SUs never perforate a rubber diaphragm (because they don't have them) so I think the balance still lies with the SU.

It surprises me that, say, TR4A or TR-6 owners wouldn't grab a pair of Volvo HS-6 carbs to use on their cars, in place of the CDSEs.
 
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