hi all,
i was wondering what the relative merits of SU and Stromberg carburettors are.
i was wondering what the relative merits of SU and Stromberg carburettors are.
Why did SU lose ground to Stromberg towards the end of the carburettor period.
SU certainly seems to have the 'name', for what ever that's worth but Strombergs appear so similar in design it is difficult to know. Obviously the Stromberg has the diaphragm that can be problematic but otherwise they seem every bit the equal of SU.
My MGB has HS6 SUs (1 3/4) and my Humber has early Mk1 175CD Strombergs. If asked the question I would say the Strombergs were ahead of the SUs but that may be heresy.
Was there any performance difference between the two carbs?
Are Strombergs inherently less polluting?Somehow SUs seem to have more of a presence in an engine bay
Al
SU certainly seems to have the 'name', for what ever that's worth but Strombergs appear so similar in design it is difficult to know. Obviously the Stromberg has the diaphragm that can be problematic but otherwise they seem every bit the equal of SU.
My MGB has HS6 SUs (1 3/4) and my Humber has early Mk1 175CD Strombergs. If asked the question I would say the Strombergs were ahead of the SUs but that may be heresy.
Was there any performance difference between the two carbs?
Are Strombergs inherently less polluting?Somehow SUs seem to have more of a presence in an engine bay
Al
Doug
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I'm not an authority on the matter but my impression is that Stromberg came up with a design that was more tune-able for emissions purposes. Apparently they don't flow as well, though....as they're often referred to as "Strangle Bergs". Urban legend? I dunno.
My guess is that other emission equipment played a role as well...but the carbs get all the blame.
Cheers
DD
My guess is that other emission equipment played a role as well...but the carbs get all the blame.
Cheers
DD
Grant Francis
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I am with Doug here.
We got Strombergs near the end of the S2 XJ6 Jaguar, but the Daimler version retained the HS8 SU, and the early V12 had Strombergs.
All the early 6 cyl were easily able to be converted to SU, and kits were readily available in the day.
I prefer the SU for simplistic design, and once set correctly rarely need "fiddling".
Which is better????, no idea, depends a lot on what you are familiar with I suppose
We got Strombergs near the end of the S2 XJ6 Jaguar, but the Daimler version retained the HS8 SU, and the early V12 had Strombergs.
All the early 6 cyl were easily able to be converted to SU, and kits were readily available in the day.
I prefer the SU for simplistic design, and once set correctly rarely need "fiddling".
Which is better????, no idea, depends a lot on what you are familiar with I suppose
Junior Member
I might simply add that although the Strombergs have some settings and additions for emissions (as noted above), they can be easily closed or tightened off.
And from my experience having older saloons with the SUs and a later E Type with the Strombergs, I never ONCE touched the Strombergs. Not in any shape or form, and it was a daily driver in the late 90s early 00s .. Perfect plug colors on all.
They get a bad rep for stealing power somehow, and honestly I don't understand why or how. What WOULD cause power reduction issues on later cars are the secondary throttle bodies and distributor that does not allow for advanced timing, only retard.
Other than other emission related stuff tacked on like a child's band aid, which again can all be removed or plugged, I don't know how the Stroms would reduce power themselves compared to HS8s etc.
I would like to see a definitive answer as to why this myth/reputation perpetuates actually.
But again, of all the cars I had, I never had to touch the Strombergs.
FWIW
And from my experience having older saloons with the SUs and a later E Type with the Strombergs, I never ONCE touched the Strombergs. Not in any shape or form, and it was a daily driver in the late 90s early 00s .. Perfect plug colors on all.
They get a bad rep for stealing power somehow, and honestly I don't understand why or how. What WOULD cause power reduction issues on later cars are the secondary throttle bodies and distributor that does not allow for advanced timing, only retard.
Other than other emission related stuff tacked on like a child's band aid, which again can all be removed or plugged, I don't know how the Stroms would reduce power themselves compared to HS8s etc.
I would like to see a definitive answer as to why this myth/reputation perpetuates actually.
But again, of all the cars I had, I never had to touch the Strombergs.
FWIW
o1xjr
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I have HS8's on my XJ6, very easy to work with & set up. I owned an LJ Torana the same year as my XJ6 30 years ago, it had from memory....Stromberg CD150 tripple carby's . Never touched them in 2 years of owning the car.