9 replies to this topic

[BiMU]

Just wondering... I have a 1275 metro lump and seen alot of minis with webers... so its got me interested. What does a Weber carb actually do? And why do people often add one? Are they also relatively easy to fit?

Sorry if its a dumb question, i would just like to know!

Thanks in advance! Jai

[minivanman]

they are used in racecars and performance engines more because they dont tend to go out of tune like SUs. They are very accurate, and set up correctly they can give good economy. plus they look the dogs danglies. They can make a real difference to performance, but for your engine I wouldnt imagine there would be any real benefit over a HIF44. To fit one you need to add a box in your bulkhead to allow clearance for the added length of the inlet manifold and air filter.

[Dog]

You only really need to fit a box if u fit the best manifold! a stright 6-7"... or go for a swan neck, but there really is no point!!!

a good HIF44 is good, but its still a single carb... go twin's if you fancy using the power in 1st n 2nd... tis what I am/have done... but got one stage further, I have gone for HIF4's... these are like the HIF38/44, only in twin version, these do require bulkhead mods too, but its well worth it!!!

[BiMU]

plus they look the dogs danglies. They can make a real difference to performance, but for your engine I wouldnt imagine there would be any real benefit over a HIF44.

I think it was a twin weber that i saw... and it was sure was danglin'!

a good HIF44 is good, but its still a single carb... go twin's if you fancy using the power in 1st n 2nd... tis what I am/have done... but got one stage further, I have gone for HIF4's... these are like the HIF38/44, only in twin version, these do require bulkhead mods too, but its well worth it!!!

Ah so Im guessing that i have a HIF44 carb then? How can i tell if its in good nick?

 DSC00725.JPG   82.27K   19 downloads

(oh and yes i do still need to fit a choke cable!)

Edited by BiMU, 28 July 2006 - 09:32 PM.

[Dog]

Yep thats a HIF44...

is it in good nick? Does it work?

If the answer to that is yes, then yep it'll do.

Only way it'll be in tip top con, is if u rebuilt it, but treat your Mini to a rolling road... it'll way worth it!!!

[BiMU]

Yep thats a HIF44...

is it in good nick? Does it work?

If the answer to that is yes, then yep it'll do.

Only way it'll be in tip top con, is if u rebuilt it, but treat your Mini to a rolling road... it'll way worth it!!!

I think i'll treat it after...

Oil leak sorted (gearbox change)
Steering column replaced
m.o.t pass


...oh yeah and when i return from canada!

[The Matt]

Weber are basically just another manufacturer of carbs, just like SU, Stromberg, Zenith, Amal and so on. There are various types of Weber carb for different applications, some of them are totally standard and can be seen fitted to things like Fiestas, Novas, Fiats etc. as standard. There are loads of carb options available for Minis, some of which are not necessarily a performance upgrade, but just a different brand of carburettor.

Some of the carbs made by Weber are seen as a performance upgrade though, for instance their DCOE range (40, 45 etc. where the number refers to the size of the barrels of the carb). In alot of peoples opinions though, a standard DCOE 40 is no better than a well modded/setup HIF44.

For a failry standard 1275cc engine, the HIF44 is a good all rounder and can also be tuned well enough to give a good amount of grunt! If you want to really increase an engines performance it takes more than just a carburettor to get good results.

As DOG has said up there ^^^^ to get the best results from a DCOE 40 or 45 you need to fit a nice long, straighter inlet manifold, which results in modifcations to the bulkhead (AKA Weber box).

[BiMU]

As DOG has said up there ^^^^ to get the best results from a DCOE 40 or 45 you need to fit a nice long, straighter inlet manifold, which results in modifcations to the bulkhead (AKA Weber box).

Thanks MMM. So im guessing that you have a Twin-Weber set up from your signature pic with a Weber box. All the info you lot have given will do me a whole lot of good. Now i know what some of you mad mini peeps are banging on about. I'll just make sure mine is running in top condition i suppose.

Also what do people mean when they change the 'needle' presumebly from within the carb somewhere!?

[Dan]

A Weber is simply no where near as accurate or fuel efficient as an SU. It's a fixed venturi card with fixed jets, as MMM says the DCOE will produce a very similar mixture flow as an HIF44 but it will do so at the expense of a lot more fuel. They are not and cannot be fuel efficient due to their design. My opinion is that they simply aren't worth it for road cars and most racers aren't allowed to fit one due to series regs. You will see very little difference between your HIF and a DCOE.

MMMs setup in the sig is a single Weber, they are twin choke carbs. Twin Webers are more of a waste of money again as in a conventional Mini you can only use one choke from each carb. All they do is allow you to use a better design manifold without fitting a Weber box.

The needle is part of the fuel metering system in an SU carb. In conjunction with the vacuum chamber spring and type of oil in the dashpot it forms the fuel 'map' for the engine.

Edited by Dan, 29 July 2006 - 09:30 AM.

[BiMU]

A Weber is simply no where near as accurate or fuel efficient as an SU. It's a fixed venturi card with fixed jets, as MMM says the DCOE will produce a very similar mixture flow as an HIF44 but it will do so at the expense of a lot more fuel. They are not and cannot be fuel efficient due to their design. My opinion is that they simply aren't worth it for road cars and most racers aren't allowed to fit one due to series regs. You will see very little difference between your HIF and a DCOE.

MMMs setup in the sig is a single Weber, they are twin choke carbs. Twin Webers are more of a waste of money again as in a conventional Mini you can only use one choke from each carb. All they do is allow you to use a better design manifold without fitting a Weber box.

The needle is part of the fuel metering system in an SU carb. In conjunction with the vacuum chamber spring and type of oil in the dashpot it forms the fuel 'map' for the engine.

Cheers Dan! As u can see i have to do a lot to my mini far! Doesnt help when Im in vancouver. I seen 3 mini's so far; 2 mk 1's and another mk 2 or 3!