Twin SU's or twin Weber?

What are the pros and cons?
Which are better?
Is it just personal preference?

I engine dynoed both a Dellorto 45 (Weber clone, 38mm chokes) and an HS6 SU on my 1412 stroker.
HP was much the same, but the HS6 gave 113ft/lb torque (on RE7" manifold) and the Dellorto only 108ft/lb at the CRANK.

I like the Dellorto better though, as it has better throttle response from 2500rpm up, and it makes music.
SU gives better economy.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

That's one for the Weber, music beats economy in my book

I have 2 1275s one a weber and the other SU the weber is my choice sounds better and response drives nicer

Two votes for the Weber

Any support for the SU???

IMO sidedraft Webers & Dellortos are easier to tune, IF you have an A/F ratio meter.
With an SU you are never sure that the needle you are using (out of the 700? available) is the optimum one.

[Waits for GR the SU man to jump on here and demolish my arguments..]

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

I would choose an SU over a weber anyday (except Sunday). Sure, Webers are great for a weekend drive, they sound great and they're responsive, but they chew through too much fuel for a daily driver.

Interesting that Vizard says get the biggest needle in the SU and use a file to adjust. I'd leave that for an expert. I'd imagine that you'd spend a fortune on dyno time to get it right.

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The bitterness of poor quality (or Crappy Workmanship) remains LONG AFTER the Sweet Taste of Low Price is forgotten.

My mechanics did that for my mini. Makes a world of difference if you know what you're doing.

I recently changed from twin 1-1/4 SU's to a 40mm Weber on my mildly worked 1100.

The SU's were actually a fantastic setup, and I'd have no hesitation in putting them on another mini in the future. The reason I switched to the Weber was purely for the sound, but I've also found that it suits my driving style better than the SU's

What I found nice about the SU's -

They are quiet compared to the Weber
They are smooth as hell when tuned properly and make for a very well behaved car for use around town. no popping, burbling and growling.
The car starts first go with the SU's, this might just be due to the current tune with my Weber (it's getting dyno'd / tuned on Tuesday!)

What I found a bit of a let down with the SU's -

They are quiet compared to a Weber
They seem to only have 2 throttle positions, light throttle and full throttle. This is more than likely to do with my actual engine configuration, but I'm just talking about personal experience here.
I found that it was easy to find someone who can tune a Weber properly compared to twin SU's (personal experience here also!)

What I like about the Weber -

The sound
It just looks better (personal opinion of course!) eg cleaner looking engine bay etc
Many adjustments to get the exact setup / drivability that you need
The sound
Feels like there are 3 - 4 distinct throttle positions and levels of noise to go with these positions.
Feels more responsive than the SU's

Honestly, as a daily driver I'd highly recommend the SU's ... they are just so much nicer around town. However, if you want a tough sounding mini... the Weber will certainly do it for you!!

Please take my post with a grain of salt, this is what I like, this may not be what you like or even the same thoughts as others have... it's just my opinion.

More than happy to take you for a drive in my car to see if you like the sound / drivability if you're in the Sydney area

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1968 Mini-matic - 1340cc, 45 weber - 92hpatw, 14.5 @91mph, GrandmaSpec

Just read that you are in Perth oops

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1968 Mini-matic - 1340cc, 45 weber - 92hpatw, 14.5 @91mph, GrandmaSpec

Cheers Chux, it's personal opinion I'm after so thank you.

My current engine is a mildly worked 1100 with twin SU's so just wanted to hear others thoughts as I'm thinking maybe trying the Weber (I've had a lot of old Fiat's and Ducati's in the past so am familiar with Webers).

What a great post Chux. Totally confirmed my switch from twin HS4 SUs to a 45.!

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http://www.rylstoneclassic.com

Horses for courses.
Can't really compare unless you also add the manifold, any carb tweaks into play, and then at optimum they are both in the same ball park. I think i read twin HS4's are good for about 110 HP whereas the Hif44 and Weber/Dellorto 45 can go near 150 on the Group Nb/c cars.

For most street cars as Doc said, close call. There are good and terrible examples of inlet manifolds around that can make a big difference.
I have heard some of the big BIG bore ( talking over 1450 cc) using twin HS6 or twin dellorto 40s - like the alphas, fiats of yesteryear -

My street car has twins and is fun but respectable.- but i have an AFR meter to assist tuning - so no dollars spent on dyno.

In Vizard's book he says that the "best" one is often the one you have already. There isn't much difference in hp for a well tuned carb on a good manifold with a decent flowing head to another type of carb.

If you want a Weber, then buy a Weber, otherwise keep the SU...

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