bigger venturies on 32pdsits?

[baggabones]

just rubuilt a pair of 32pdits for my '67 square...someone told me that larger venturies than stock are available and fitting a larger size may increase performance on an otherwise stock engine?.....any thoughts or help please?

[Mike Fisher]

www.Aircooled.net lists a lot of Solex jets etc. www.cbperformance.com sells a new set of 34mm Solex's for bus/914. Would 34mm bolt onto 32mm manifolds?
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[66311]

Sure. Is it dual port? What size do you have now? Jets? You can use bus venturi for even larger size and should match up or experiement jet sizes. I recommend Bill Fischer's book for some good overall advice. Also this has come up in forum so a search may turn up some practical experience.
I am running a single port with later model larger sizes. All tuned up it works great but debatable if there is actually a performance difference because the originals had worn throttle plates. There does seem to be more higher end power for hills. The power fuel tubes seem to function well. Most of the fun has been noticing the small increases and imagination. But I think a dual port could benefit from even larger sizes.
All else decent it is really the throttle plates that make all the difference for Solex. If they are worn get a fresh rebush.

[baggabones]

Dual port yes. All standard - carbs jets etc, and manifolds.....taken venturies out and just wondered is all...throttle spindles rebushed and all tight....so I guess I need to re-jet if I get larger venturies?.....been reading an old 60's copy of hot rod and custom magazine where they reworked a solex 28pict and filed out the venturies and reworked the discharge tube and gained an extra 14 hp!!??....wondering whether to try that or go go for for the larger off the shelf venturies, off a bus or whatever?

[66311]

There were different sizes for 32s. I would try the bus venturi and then work out jets. Interesting is that you may experiment with different combos including dwell/timing to get want you want. Combinations are many but I wouldn't look for a 15% gain as likely.
My wish list for a dual port is bus venturis with power fuel circuit and work out the jets. The 32s can pull some fuel. After reading some vintage power books I was convinced the limits of 32s are suitable for larger engines. Then I ran into someone this summer running a 2 litre on 32s with bus venturi and jets(IIRC) Anyhow he cracked the stock air cleaner at the higher RPMs.
Point is certainly there is more available for an otherwise stock engine. Factory tuning was detuning

[notchboy]

Ha! Jimmy and I were just talking about this. You can bump your 32s up to 34s by looking into what Mike showed-CB site for Bus 34 Solex stuff. Now thats for new stuff or you can just buy some dual 34 Bus carbs and take what you neet-venturi, jets.
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[blankmange]

running that very carburetor set up on my 1776 now:

http://www.thesamba.com/vw/forum/viewtopic.php?p=4868194#4868194

[baggabones]

well i got some 32-34 pdsits off a bus but the venturies seem the same size, was hoping they were bigger

[blankmange]

[notchboy]

[blankmange]

[GMendoza]

Don't forget to re-jet after changing the venturies.
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[asesapie]

ok lets say i bought a set of those new solex's from cb, would they mount onto the stock dual port dual carb manifolds?? and would the linkage and everything else work minus the stock oil bath air cleaner?
has anyone used these on a type 3 or squareback for instance?
thats what i would be curious to use them on

[notchboy]

Yes they would fit the manifolds. But Im unsure about any kind of linkage or if you can put T3 linkage on them.
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[baggabones]

Got a set of bus carbs thinking they'd have the bigger vents, same vent size (24mm), but 150 main jets??.....guessing these will be far too large to use on my 1600 32 pdsits, unless i up the vents, yes?

[Itawayoflife]

I'm actually thinking of doing this to my fasty.

A few weeks ago I went on the DKP toy drive cruise and my car would not take the hills. It's only a 1600 single port, so, I know I can't expect much from it. It still has a factory exhaust, distributor and carbs.

This past summer, I bought a 1600 single port from some Trike people in Bakersfield. Needless to say, the motor was a completely wasted, but they gave me a bunch of extra parts, so it wasn't a total loss. Mixed in with the parts was a brand new set of 32-34 PDSI carbs. I tried selling these things for a while but found that trying to explain to people how to fit them to a type 3 was more trouble than it was worth. So, I kept them only to find out that they are actually a set of the CB Performance 34's.

My plan is to squeeze as much out of this 1600sp as I can using bolt-on items. Similar to what they did in the Bill Fisher book. I know this has been done hundreds of times, but I want to try this for myself and do it all at once so, if there is any significant increase, then I will be able to notice it.

I already have the carbs and an 019 in good running order. All I need now is the header/muffler, the larger venturis (from CB) and a set of 1.4 ratio rockers.
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