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SUs or Weber?

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Though I prefer the SU, I agree with George here that if you can't get it going correctly, the Weber 32/36 works. Works well even!

The DCOE is a real screamer, but takes a lot of knowledge to get it set up right. (This is well documented in the Vizard book)

The SU is easy enough, but I always hated the needle "numbering" system. There is fortunately a program WinSU to help with that choice. It costs a bit of money. Other than that the SU is a wonderful carb. Flexible enough for different operating conditions. Few moving parts for durability. Reasonably good with mixture control (good economy). Actually the biggest problem is the siamese ports on the head.

Actually I had a pair of 45 DCOEs on my Volvo Amazon. It took a month to adjust properly with my limited equipment. In the end it was really perfect. Good economy (25mpg), started easily when cold, no flat spots, extreemly powerful etc. Until one day I broke the gearbox, driveshaft and differential - all at one time. It was too hot and the clutch was too unforgiving. Now I have the single 1.75 Stromberg back on it.
 
Is there a good book/manual that does a decent job walking a newbie through a rebuild? Santa might have to get me one. I can work my way through them at my leisure and swap intakes/carb when I feel like it and if stinks, swap back and try again.
 
I have a copy of the Haynes carburator manual which covers both SU and Zenith/Stromberg carbs as well as Weber. Each section is very well written and documented with photos and charts of tuning information. A very good basic manual to begin to set up and rebuild any of these carbs. https://www.amazon.com/Haynes-Zenith-Stro...1480&sr=1-1
 
racingenglishcars said:
(This is well documented in the Vizard book)
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I was hoping someone would mention The Book. This subject is quite thoroughly covered, across four chapters.

Vizard.jpg


For example, In Minis, running the stock 1275, the single HIF6, Minispares alloy manifold, K&N, LCB header, ~1 1/4" ID pipe and Maniflow exhaust is a proven, reliable combination. Great performer, good on fuel, street friendly. I've run this combo on several Minis, and currently on my Midget. Happy times.
 
That one's on my Christmas list already!
 
<span style="font-weight: bold">Hap rebuilt my SU HIFs which replaced this and I couldn't be happier! </span>

weber1.jpg


<span style="font-weight: bold">It has a flat spot on acceleration that won't disappear.</span>
<span style="font-weight: bold">I now use it for a paper weight and to remind me never to put another one on a "B" engine! </span>
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Amazon.com carries that book for $30.36 and is in stock, there are also new and used ones selling for 24.28 and up on their site located here: Tuning the A-Series Engine

Will be getting one for Christmas :smile:

Thanks Bill

Dan
 
Hey I need a paper weight like that, wink wink, nudge nudge... Got a 74 Midget with a 1275 waiting in the wings for restoration.
 
scubabatdan said:
Amazon.com carries that book for $30.36 and is in stock, there are also new and used ones selling for 24.28 and up on their site located here: Tuning the A-Series Engine

Will be getting one for Christmas :smile:

Thanks Bill

Dan
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No sweat. I did fourteen years myself. Last post was D 2/327 INF 101ST ABN.
 
well I have a weber DGV and oh yea its a pain to get it rite but I did and it works just fine. Sure it seems they all come out of the box running so rich it burns your eyes. but with some reading and a bunch of jets and air correctors you can get rid of the notorius 2300 stomp flat spot and make it fly and idle good. It just takes time. I didn't have a choice as the setup came with a box of stuff and my budget didn't allow to change at the time. Heck I'm happy with mine like I said it just takes time and a bunch of jets and pizza and a few beers.
'
 
Toss the weber. I tuned it with a air fuel gauge and it still gave horrible performance. I went to one 1/2" su and it performs better than that weber ever did. Set it once and has been great since.
 
texas_bugeye said:
well I have a weber DGV and oh yea its a pain to get it rite but I did and it works just fine. Sure it seems they all come out of the box running so rich it burns your eyes. but with some reading and a bunch of jets and air correctors you can get rid of the notorius 2300 stomp flat spot and make it fly and idle good. It just takes time. I didn't have a choice as the setup came with a box of stuff and my budget didn't allow to change at the time. Heck I'm happy with mine like I said it just takes time and a bunch of jets and pizza and a few beers.
'
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Chris, what jets,(size), did you use? The pizza and beer have already been tried. Fixed me, but not the carb!
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I wrote my jet sizes down but can't find them at the moment. I don't have much carb experience either way. Spent some quality time with a Weber 38/38 on my old Opel and learned a lot but not so much that I feel I have to forgo the SUs.
Weber you have main jets, idle jets, emulsion tubes and mixture settings, progressive style the primary and secondary are different enough that you treat them as separate and therefore multiply the combination by two. Without a good gas analyzer or multiple dyno runs it's all guess work. Jets are easy to swap around but you really need $100 worth of jets sitting there and play with different combinations of settings, the variations of which can be endless. On my Opel I picked the brains of experts and got it pretty close before the WRECK. (sold the carb BTW).
I guess a better questions is; What's better, a properly set up Weber 32/36 or properly set up twin HS2s?
Why are Weber's popular? Is "instant performance gain" a myth or is it the perceived convenience of a "bolt on" replacements for worn SUs? Seems you take a BIG hit on mpg with a Weber, there's reason enough to ditch it, if performance is as good or better and mpg is MUCH better, SUs for me.
 
According to Vizard you can get great performance out of stock 1 1/4" dual SU's though simple modification of the Stock intake manifold. I picked up an extra in a grab bag of parts from ebay and am in the middle of doing the mods. Waiting for a Dremmel tool for Christmas instead of the hand files I started with. I'll keep ya'll posted.
 
Cool. I did some mild intake manifold work on the Opel. I assume that's what Vizard talks about.
I'll just work on other things until I have some books. One thing that concerns me a bit is I tapped the Pierce intake for a vacuum line which did wonders for oil leaks, if I switch back to SUs than I have to either go back to a line on the air cleaner housing (as per stock), or somehow tap the standard intake manifold. I don't relish the thought of making more problems but I guess that's part of the fun.
 
I cant get to my work sheet on the jetting. But here is an article that walks you thru the setup of the DGV. There's a guy in Italy that sells jets on Ebay dirt cheap someone mentioned him on the this topic on another thread if some one remembers please help out here. He has a good varity of jets and air correctors there the good ones with the large beefy slots.Takes about 5 -7 days to get them.
Read thru this and you will have a basic understanding of how to tune the weber DGV to suit your engine. https://www.dimequarterly.tierranet.com/articles/tech_weber_tuning.html

And if anyone whats to donate a set of Nice SU's to a really nice 59 sprite in texas Just let me know.
Poca Rossa Sprite would be very happy till than she will be motoring on a weber.

Good luck hope itall works out.
 
Alpha1750 is the ebay guy from Italy who does carb parts. I got jets for my old Weber from him, good guy, good service fast shipping (even from Italy, about 1 week). Just ask him to mix up whatever jets you "think" you'll need and he'll fill the order. Beats paying $80 for a jet kit with stuff in it you know you'll never use.
https://stores.ebay.com/ALFA1750S-CARBURETORS-PARTS-STORE[/url
 
I have the HIF 44 on a Titan manifold, set it up first with a BDL needle - too lean. The BDK is just right for me (266 cam, 1.5:1 rockers, 10:1 CR, LCB header, megajolt ditributorless ignition) Loads of torque and the convenience of set once and forget - I got the manifold from ATP but I understand they can be tough to find. Just saw an HIF 44 from a mini with manifold on ebay, last bidding was at $99, you can trim the face angle of the mini manifold to drop the carb down some to clear the bonnet.
 
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