19 replies to this topic

[Nightrain]

a twin hs2 carb would be more suited to a 1275

Wouldn't be a wise investment for the future though, the weber will work well with either a 998 or a 1380.

[zebidee]

I had thought about twin HS2's, especially considering that they come up quite cheap second hand. Im not too bothered about moving the carbs on to my next engine, haven't decided what to run it with carb wise yet, so its just for fun right at this moment !
So what should i expect to see out of a 28/36 DCD?

[cap'n crunch]

Cap'n crunch...are you running a 28/36 DCD at the moment?

Yep and before that i ran Twin HS2 on the exact same engine.

Personally i see it like this

Weber 28/36

PRO - Not many people use them so are unique, Once they are set up for your engine that is it no more tuning required, Give both Efficency and Max Power as they are progressive twin choke. Parts are still easy to get hold of. Looks cool. Throttle response is great low down due to the small primary venturi and really pulls when you open up the secondary.

CON - A-series Manifolds are rare as rocking horse manure, needs someone who knows webers to tune it (though most mini/classic car friendly garages or rolling roads are), had to make my own throttle linkage, my particular inlet and exhaust manifold fouled on each other before i had it machined.

Twin SU

PRO - more spare parts than you can shake a stick at, good throttle response, v.efficent mini carb and good max power. Good mixture spread between cylinders due to no turns leading in the cylinder head. has the classic mini look and style.

CON - Constant tweaking and do go out of tune, carb icing, If the dashpot oil is to thin or too thick it adversly effects acceleration. Even less space in the engine bay.


I would say Weber every time, as i get better MPG, no carb icing, better response through out the range, No more messing around with the mixture and the idle adjustments, no more changing the daspot oil, the great sound when i get to 4k rpm and open up both chokes.

Max Power wise overall BHP will probably be within 3-5 bhp of each other and the same goes for torque. So either you do not lose or gain in perfomance numbers.

[Nightrain]

So what should i expect to see out of a 28/36 DCD?

How longs a piece of string, they where fitted as standard to 1600GT cortina's and escortsGt's which had around 90hp. I personally fitted one to my MG Metro and it transformed the performance and increased the economy. Sure a mate had around 100 out of his 1380, my own Minisport 1380 shouldn't really be counted and had lot's of issues. That had nothing to do with the carb gave 87 and was slower than the MG I had the carb on previously.

[zebidee]

I meant how would its throttle response & economy and such fair, i wasn't really expecting you to estimate horsepower out of it don't worry . I would love to try a Weber, but im always tempted to 'play it safe' and stick with the twin SU idea. Thanks for both of your help so far by the way , its interesting learning a bit more about them!

Edited by zebidee, 28 April 2009 - 08:58 PM.