+- Austinsevenfriends (https://www.austinsevenfriends.co.uk/forum)
+-- Forum: Austin Seven Friends Forum (https://www.austinsevenfriends.co.uk/forum/forumdisplay.php?fid=1)
+--- Forum: Forum chat... (https://www.austinsevenfriends.co.uk/forum/forumdisplay.php?fid=14)
+--- Thread: Twin Zenith or Solex carbs (/showthread.php?tid=2481)
Twin Zenith or Solex carbs - Scarlet O'Hara - 05-03-2019
Would be interested in comments on the following arrangements of fitting twin carbs but at the same time trying to keep a more period apperance than fitting a 4 branch exhaust manifold and some modern SU's. Just a bit of fun really to keep idle hands occupied. I suspect there might be too much heat transference from the exhaust.
Zenith 1.JPG (Size: 343.39 KB / Downloads: 582)
RE: Twin Zenith or Solex carbs - Zetomagneto - 05-03-2019
looks the vintage business, nice work.Not sure on the performance side of things
RE: Twin Zenith or Solex carbs - Mike Costigan - 05-03-2019
It's a shame they're not handed the other way round - it would be better with the float chambers at the front ...
RE: Twin Zenith or Solex carbs - Speedex750 - 05-03-2019
Looks the part. The gaskets between the manifolds and inlet to carbs will give some insulation, a small aluminium heat shield curling under the float chambers may also help. A throttle linkage will be your next problem, is 'open' in a forward or rearwards pulling motion? It looks rearward to me?
Dave
RE: Twin Zenith or Solex carbs - Chris KC - 05-03-2019
I don't see any obvious reason why it wouldn't go alright once 'tuned' - set-up would be the tricky bit.
RE: Twin Zenith or Solex carbs - Steve Jones - 05-03-2019
As Mike Costigan says, above, the float chambers should be to the front, not the rear. Both pairs of carburettors are made for engines that have them mounted on the Off-Side. Mounted on the Near-Side as these are, they will be constantly trying to fight gravity - apart from when going down hill.
Steve
RE: Twin Zenith or Solex carbs - Charles P - 05-03-2019
I recall reading Solex literature of the period claiming that it didn't matter if the float chamber was ahead or behind.
Charles
RE: Twin Zenith or Solex carbs - Steve Jones - 05-03-2019
(05-03-2019, 08:37 PM)Charles P Wrote: I recall reading Solex literature of the period claiming that it didn't matter if the float chamber was ahead or behind.
Charles
Claims and practice can be different things.
Solex carburettors can be tricky. It can't be a coincidence that many (most?) Meadows 4ED applications originally fitted with Solex carbs are now running with SUs. Having been there, done that, with a single Solex I fear that setting up a twin pair could be something to give you sleepless nights!Steve
RE: Twin Zenith or Solex carbs - Robert Foreman - 05-03-2019
Solex carburettor's were available with left or right hand float chambers.
I agree with Steve and Mike that the float chamber should be to the front otherwise starvation can occur when hillclimbing.
Obviously I don't have any problems setting up Solex's and am now a worldwide ambassador for them.
RE: Twin Zenith or Solex carbs - Charles P - 05-03-2019
I got it wrong.
It wasn't Solex who said that but John Howell in his seminal article on Carbs for Vintage Racing Cars in the VSCC Bulletin back in the mid 80's. Argue with him at your peril Steve!
SU's are undoubtedly easier to tune - merely polish a needle on the rolling road. That's the appeal. With a Solex you need jets and chokes to swap around.
Hopefully these extracts are readable.
Solex 2.jpg (Size: 235.85 KB / Downloads: 364)