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SUs or Weber?

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jvandyke

jvandyke

Luke Skywalker
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My 1098 has a Weber 32/36, Pierce manifold, Pacesetter header straight to Monza exhaust. Manual choke.
Runs fair, never tried to tweak it much last season. Hesitates on hard exceleration, could be timing never messed much with it either, have a Crane Cams XR700 I was intending to fit.
PO included a pair of SUs, the originals I'd guess, LOOK to be in good shape, still on the manifold with heatshield.
Looking for input/advice on which would be a better way to go.
SUs may need a rebuild or extensive fiddling. Weber likely needs little beyond possible jet tweaking.
What is theoretically the better setup for this 1098? Or is this a matter of opinion?
I've read the SUs can be more responsive "quicker" and suffer a tad on the high end. Weber the opposite.
I'd prefer it to be as "quick" as it can and don't care about top end so much.
Just trying to decide where to spend my time and $$ first.
 
My vote would be for the twin HS2s, I'll be happy to rebuild them for you.
 

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I live close to University Motors (John Twist). I mentioned my carb indecision to their secretary when I was in there last week, she said they pulled three Webers off this past season. They'd rebuild mine for about $600 (yikes). I can take a workshop they offer in a few months and do it under supervision ($600 for class and parts I'd imagine) which would be fun, love to take the gearbox one they do too. These are too $$ for a working family man though, always something more pressing for the household then that kind of $$ on dad's toy!
I could just swap 'em and fiddle, not that much involved in swapping back in forth, other than re-introducing manifold leaks everytime.
 
I abhor Webers! Nothing can be better than a set of properly built & tuned SU's, IMHO!

I just bought a fine running early pull handle MGB...if I keep it, the first thing that will go is the Weber setup!
 
tony barnhill said:
I abhor Webers!
Click to expand...

Why? crappy performance or is the purist in you? (not a bad thing).
In my old Opel world, we'd ditch the stock Solex in a heartbeat for Webers, Solex's would be considered crappy compared to SUs I'd imagine.
 
jvandyke said:
tony barnhill said:
I abhor Webers!
Click to expand...

Why? crappy performance or is the purist in you? (not a bad thing).
In my old Opel world, we'd ditch the stock Solex in a heartbeat for Webers, Solex's would be considered crappy compared to SUs I'd imagine.
Click to expand...
No, not purist...crappy performance: I feel a dead spot in Webers as I'm accelerating...never have figured out how to get rid of it & most people don't feel it - but I do. That, plus, the fact that I never can tell enough difference to spend the money to convert when I can properly do up a set of SU's cheaper.
 
I don't abhor Webers, but like other carburators that have no means of limiting throttle opening rates have to have a accelerator pump and intermediate mixture circuit in order to have smooth or reasonably smooth acceleration. If correctly set up, with proper pump volume, rate, jets etc they are fine, but it takes a lot of time, trial and error to get one right on, hence the price. SU's on the other hand have than nice vacuum operated slide that only opens as wide as the engine demand allows it and also alters the mixture according to it's opening position if the needle is selected correctly. That makes for extremely smooth acceleration charateristics without any bog or lag. A few relatively simple mods make them capable of flowing as much as most any MG engine needs. I've personally seen a vintage racing B with 1.75s blow off a half dozen others with 2" SUs fitted, you don't need a huge carb if they're set up right. Check your carbs out for wear and if you have any doubts have them rebuilt by someone like Hap or Jimmy Hilton. I don't think you'll be disappointed.
 
I have always found that the constant gas smell from Webers is hard for me to bear. It seems to come from a rich mixture at low and mid range and contributes to the hesitation/flat spot that so many complain about. There are thousands of combinations of internal parts for Webers of which only a couple are correct. It is easy to get almost close to good running, but it is a long and possibly expensive process to get them perfect. With SU's your choices are much less and it is easier to get great driveability although they will never make the ultimate wide open throttle power of a Weber set-up. Just my 2 cents worth....
 
Great stuff, when I stomp my pedal I get a bog and gradual recovery, normal driving is fine, cruising at 80mph is fine, I can't see ever wanting more top end but the bog on acceleration is annoying. Can't blame the Weber though as I haven't tuned enough to know what's going on. Maybe I'll just play with the SUs and keep the Weber on hand until I decide which works best. I should be able to get the SUs operation on my own with minimum $$$, as much as I'd love to have a pro rebuild them, it's just too expensive.
 
I rebuild just the two carbs for $375.00, 405.00 if new throttle disc are needed and if so always go back with early style solid throttle disc. If you go the DIY route see Joe Curto for parts, don't waste your time with the catch-all vendors , Curto know his SU parts. Replace the standard shafts as well, parts will run you about $175.00.
 
I removed my Weber for the drive to Missouri when gas was $4 a gallon and the Weber got 22 mpg. My twin SUs got 42 mpg for most of the 1200 mile trip but I also installed a cruise control in the Sprite so I think that helped too.
I also (just this past weekend) took the Weber off my Austin A40 and put on a 1.75
SU.
My Sprite with the SUs is just as fast as it was with the Weber, the A40 on the other hand really needs the Weber if it wants to get out of it's own way on an on ramp. But we don't do much long distance or freeway driving in the A40 and the mileage doubled on that car too.
Properly tuned twin 1.25 SUs are as good in the performance category as a Weber DCOE. But the Weber sure beats the 1.75 single SU from my expierience.
 
My vote would be for the SU's in a heartbeat. The Weber is an OK carb. I converted to one on an AMC 6 cyl a few years ago and it was less troublesome than the Carter that was on there, but not what I expected.
The SU's have an unwarranted reputation for needing a lot of tuning and maintenance, but I have found them to be reliable and relatively troublefree in the four cars I owned that had them.
 
Hey Bryan, that's your Midget in that collage picture off to the right, there isn't it? Cool. You missing those smaller grill uprights on either end?
 
According to the parts manual, it has the right number of slats, but I think it might need one more short one on each side. The black grill surround accentuates the side gaps and makes them look much larger. I am going to delve into that more this spring. The car had a Sprite grill for several years after an unfortunate episode with a phesant (that the car still wont talk about). The grill is made up from a box containing all the individual pieces that was sent to me by a friend in the Netherlands. It was made up from spare parts of his and another fellow in England. A true cosmopolitan grill. I am also looking for a good grill surround too.
 
SUs sometimes get a bad rap but so do Webers. Either oneproperly set up should do fine but the SU is so much simpler to get right. In fact the whole design consept is so much simpler that it will stay running right a lot longer too. If we're talking about a DGV then the twin SU setup will probably give better performance too. Can't say that about a DCOE though. But it is even more complex than the DGV.
 
Heck, you might be able to get half or more of the cost of the SU rebuild back by selling the Weber and Manifold.
 
A pair of SUs and really make it sing.
 
Su's or Webers. There is a vast variety of opinions.

Now if it was a DCOE, I'd say Stay with the Weber. But as it is a downdraft on an intake manifold that turns sideways, and the airfuel mixture has to turn more corners. Probably the SU is better.

I disagree, in theory with Tony on Weber for PERFORMANCE usage. My experience goes back to IDF downdrafts on VW dunebuggies, IDA's on 914 motors,all the way through to DCOE's on Triumph 6's, 260Z 6's..

The beauty of a Weber is each and every circuit can be adjusted and jetted for OPTIMUM performance. Why did Ferrari, Maserati and others come with Webers? Because the engineers knew how to dial the carburetors in properly.

Sadly, most Weber setup is incomplete. This is truly a case of a little knowledge is a dangerous thing. People will wind up getting the jetting so-so and then step off the deep end and go back to so-so and accept the lagging on hesitation higher than should be fuel mileage, rich mixtures, etc... Most people don't realize that the fuel pump circuit actually has three or four(depending on the carb design) adjustment features. so they accept imperfect setup. But it does take someone with experience and skill to PROPERLY set up a Weber.
 
Weber, Weber and Weber !!

I just converted this year and haven't been happier. I must admit - it has more to do with your knowlege of either system vs. the superiority of Weber over SU.

My SU's were never right. Couldn't find anyone to help without paying more to tune them in than a new Weber setup would cost. I have multiple friends who are familar with the Weber setup. I was up and running in less than 1 hour. As a matter of fact - it was scary how peppy the car was!

I'm not saying SU's are junk. If you don't know them, then don't believe what everyone says on how 'easy' they are to work on. They are not. Trying to get someone to help on these was like asking to borrow money. Stay with your knowlege base.

My Weber 32/36 on a 1275 is down right peppy. I was able to get it in < 1 week vs a proper rebuild from someone smart and honest like Hap would take weeks and probably more money. I'm not a purist. If you are going to go with the SU's - go with Hap. I've never heard a bad word about him or his work. My car is not a 'purist' rendition by any means - so the Weber was a no brainer.

Good Luck

George Zeck
 
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