Single carb manifold for 6 cylinder engine

[ahebron]

Anyone have experience of one of these manifolds. It is for sale locally

[zetecspit]

Looks like a case of thinking "we could" rather than "we should" (IMHO)

[RedRooster]

Looks like it's for a weber car? 

[ahebron]

Advertised as Weber or Dellorto.

Could possibly be a good manifold for a blow through carb and a turno or supercharger.

[Nick Jones]

Interesting. Never seen one before. Wonder about fuel distribution…..

[ahebron]

https://www.trademe.co.nz/a/motors/car-parts-accessories/triumph/listing/5152084303

here is the full ad

[RedRooster]

À weber is basically 2 carbs in one body, so it wouldn't be much different to twin strombergs would it? 

[hoffman900]

I would stay well clear of that manifold short of a tractor. 

[Nick Jones]

5 hours ago, RedRooster said:

À weber is basically 2 carbs in one body, so it wouldn't be much different to twin strombergs would it? 

While that is kind of true, the spacing of the two carb barrels causes a rather extreme arrangement of the runners / which I’m suspicious of.  Even flow volume and fuel distribution being the concerns.

Not sure 1 & 6 would see their share of the fuel, especially at higher rpm.

[hoffman900]

23 minutes ago, Nick Jones said:

While that is kind of true, the spacing of the two carb barrels causes a rather extreme arrangement of the runners / which I’m suspicious of.  Even flow volume and fuel distribution being the concerns.

Not sure 1 & 6 would see their share of the fuel, especially at higher rpm.

100% this. 

[RedRooster]

True, a bit more thought and they could have made the runners more or less the same length. 

[hoffman900]

43 minutes ago, RedRooster said:

True, a bit more thought and they could have made the runners more or less the same length. 

That doesn’t fix fuel distribution issues 

[RedRooster]

37 minutes ago, hoffman900 said:

That doesn’t fix fuel distribution issues 

Go on, please explain,.. weber on each set of runners which could have been made the same length? 

[Nick Jones]

As I see it, the problem is that fuel is heavier than air, so cylinders that are on a straighter line (3/4 in this case) will get more fuel as it’s happy to go straight on. Conversely, where the fuel has to make a very tight turn (1/6 in this case), they’ll get less as some of the fuel will overshoot and fail to make the turn, making the others, 3/4 especially, richer.

The standard Stromberg manifolds suffer the same issues, but I would suspect to a much lesser extent.

[JohnD]

Also for a Lynx, this looks better than the OPs log!

[Escadrille Ecosse]

19 hours ago, JohnD said:

Also for a Lynx, this looks better than the OPs log!

Blimey. Some find John!

Not convinced on that score though. Assuming Nick's argument is correct then hardly any fuel will be bothered with the journey to 2 and 4, let alone 1 and 6.

I'd steer well clear of both

 

[hoffman900]

19 hours ago, Nick Jones said:

As I see it, the problem is that fuel is heavier than air, so cylinders that on on a straighter line (3/4 in this case) will get more fuel as it’s happy to go straight on. Conversely, where the fuel has to make a very tight turn (1/6 in this case), they’ll get less as some of the fuel will overshoot and fail to make the turn, making the others, 3/4 especially, richer.

The standard Stromberg manifolds suffer the same issues, but I would suspect to a much lesser extent.

Exactly this. 
 

A manifold like this would hace major fuel distribution issues. 
 

Very easy to measure with a O2 sensor and bungs on each primary. It would be a mess with this manifold. 

[hoffman900]

19 hours ago, JohnD said:

Also for a Lynx, this looks better than the OPs log!

That still looks horrible. 

[Escadrille Ecosse]

Is it possible to fit a single Weber to a Triumph Six?

Absolutely Sir. We'll be right back in a jiffy.

Which of these offerings do you dislike the least?

or

Absolutely Sir. But why?

[hoffman900]

1 hour ago, Escadrille Ecosse said:

Is it possible to fit a single Weber to a Triumph Six?

Absolutely Sir. We'll be right back in a jiffy.

Which of these offerings do you dislike the least?

or

Absolutely Sir. But why?

I do not. 
 

if you want two barrels worth of carburetors, the best you can do is a split Weber / Solex or a Stromberg / SU / motorcycle carb split where 1-3 and 4-6 are paired. 
 

These designs are trying to force something that should never happen outside like a 35hp tractor, and even then. 

[Escadrille Ecosse]

1 hour ago, hoffman900 said:

These designs are trying to force something that should never happen outside like a 35hp tractor, and even then. 

[PaulAA]

4 hours ago, hoffman900 said:

if you want two barrels worth of carburetors, the best you can do is a split Weber / Solex or a Stromberg / SU / motorcycle carb split where 1-3 and 4-6 are paired.

My man here, who reins me in when necessary, has a stock bit of wisdom for such occasions:

"Never forget, Mr Paul - the Triumph engineers knew a thing or two"

[JohnD]

1 hour ago, PaulAA said:

My man here, who reins me in when necessary, has a stock bit of wisdom for such occasions:

"Never forget, Mr Paul - the Triumph engineers knew a thing or two"

Paul, reconnect with reality!  Have you see a Spitfire airbox?   So small, with such restrictive air hoses, that they had to drill  two holes in the sidewall to let air in!

John

[Nick Jones]

22 minutes ago, JohnD said:

Have you see a Spitfire airbox?   So small, with such restrictive air hoses, that they had to drill  two holes in the sidewall to let air in!

Ah, but this was done for a reason. This is a “solution” to the winter problem of carbs icing up (albeit a cheap and nasty one). They wanted the forward-facing cold air inlets to be a little restrictive so that a proportion of warmer air from around the manifolds would also be drawn in, preventing (maybe) icing.

Footnote is that I can tell you for a fact that this “technology” didn’t work on the 1850 - though the exhaust is on the opposite side of the head on that engine - Trying to stop your Dolly 1850 (marginal brakes at best) from 70mph on a downhill motorway slip road when the throttles are frozen at least half open is the stuff of nightmares, as is having the engine immediately rev off the end of the tacho when you finally twig what’s going on and finally dip the clutch…. 

 

 

[Sprint95m]

1 hour ago, Nick Jones said:

Ah, but this was done for a reason. This is a “solution” to the winter problem of carbs icing up (albeit a cheap and nasty one). They wanted the forward-facing cold air inlets to be a little restrictive so that a proportion of warmer air from around the manifolds would also be drawn in, preventing (maybe) icing.

Footnote is that I can tell you for a fact that this “technology” didn’t work on the 1850 - though the exhaust is on the opposite side of the head on that engine - Trying to stop your Dolly 1850 (marginal brakes at best) from 70mph on a downhill motorway slip road when the throttles are frozen at least half open is the stuff of nightmares, as is having the engine immediately rev off the end of the tacho when you finally twig what’s going on and finally dip the clutch…. 

 

 

Early Dolomites had twin Strombergs, either with or without temperature compensators, the latter were the ones to have.
From about 1974 all 1850s, as a cost saving measure, acquired SU HS4s....

I ran the early Dolomite 1850 (CD150s) through some pretty cold winters without any problems (albeit the heater took ages to do any good).
Before I put the 1850 on the road I fitted Ford XR3i calipers and VW Golf vented discs along with, of course, a high level brake light.

 

Ian