Single 40 drla jetting advice

[Albertoprop17]

Hi everyone, I have a 1.6 stockish 54 beetle, and I want to put a single 40 drla on it. The engine is fully balanced with lightened flywheel, and a tuck a way exhaust. Now I'm running a 31 carb, the difference in perfonrmance should be noticeable.

Mi 40's actually have 28 vents. Whant jets do I need? Special mods on the carb for single use?

One more question, which intake work better, empi or cb? I like more the empi linkcage but that's not relevant.

Thanks and cheers from Spain!

[Albertoprop17]

Nothing? Should I use dual 40 drla's with space saver manifolds/reverse flanges or keep thinking on the single drla?

[Alstrup]

Hello.
A centermount 40 mm Dellorto on an almost stock 1600 will be quite a challenge to get to run right, even in warm ambient where you are. It can be done of course. If you like the simplicity of a centermount stockish carb. I´d recommend a sligthly modified 34 mm Pict3 with the correct distributor on the correct 1600 manifold. That will give you a mnuch easier engine to jet, not quite the same upper end power, but easy to work with.
When I have the task of dialing in centermount Dells/IDF´s it often takes a full day with maybe 4 hours on the dyno. A stock carbed performance engine can often be done in about 1 hour
If you decide to go with a 34 mm Solex remember to use a proper aircleaner. The stock 1200 needs modification to flow properly for the 34 mm.

T

[Albertoprop17]

This is how my engine looks right now

Do the space savers be a pain in the ass to get the carbs properly adjusted in the 1-3 cylinders? Should I have more space with normal offset manifolds and reverse flanges?

And how about the mileage with the single drla and duals?

Thanks a lot

[modok]

Any single carb to work right you need a manifold that is the right size for the engine and a good air filter. in the picture I just see a little cone on the stock carb. You will gain a lot if you just put a 100mm length tube between the carb and filter. This is because long manifolds have a lot of sptiback.....reversion...."fog" or whatever you want to call it. That needs to be in a tube, not hitting the air filter. the single dellorto is the same way. You need a well designed and sized air filter and manifold to get good all around performance. You get that first, then we will discuss jetting.
The cb low profile is the best manifold. It is too big for your engine, but if you get that, and change the steel tubes from 38mm to 34-35mm OD, then maybe OK.

[j-dub]

What kind of ignition module are you using? Is it the 191 905 351 B style that came on lots of later model VWs?
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[Albertoprop17]

I understand. I'm going to search one 100mm tube to put in there. Will ot clear the decklid?

So if I get the cb low profile manifold I need to replace the 38mm tubes for 34-35mm ones. Othe thing, my actual header has not heater risers...

As I asked before, which set up has better mileage? Duals or single drla? I already have two offset 44mm manifolds, a bellcrank linkage and two 40 drla's

I was thinking of putting the velocity stacks with filters at their top

I'm actually running with an SVDA distributor with points, in the picture I was trying to put a electronic DVDA type 4 (CU engine) distributor but I had some trouble. Maybe I will try again in the future

I'm a bit lost om this matter

[j-dub]

[Alstrup]

Best fuel economy. PROPER set up Solex 34 mm Pict3 with a PROPER aircleaner set up, and NOT a stupid small cone filter, the correct distributor and a decent exhaust, or 36 Dellorto´s again with a proper distributor.
40 Dells can be made to run nice on a 1600, but they are really too large for an almost stock engine.

[Albertoprop17]

I think the best is to put a 34 pict 3 with a hi flow manifold and next jump to dual 40 drla's, with the help of the dellorto superformance book

[Alstrup]

The stock 1600 manifold works just fine on such an engine. It is much more important to get/make a decent aircleaner.

[mcdragracer]

That would have been my recommendation from the beginning just leave a 34 mm on and the stock manifold is just fine, when you're ready to step up I would go with the Dual carbs, but I would go with 36 Dells with 28 mm choke vents which is a very nice combination for your 1600 and the carbs will work great if he decides to step up with a bigger motor.
Keep it simple and running good with the 34.

[modok]

I was very pleased with a single 40 dellorto on a stock mystery 1600.

I did end up making every part except the carburetor itself. A lot of work.

but....if I had done half the amount of work to a stock solex, it probably would have been 95% as good.

[Albertoprop17]

And what are the best mods for a stock 34 pict 3 solex?

[Lingwendil]

[Alstrup]

The stock plastic aircleaner works fine and is a good solution, if you have room for it. Pre´66 cars do not have room for it.

[Albertoprop17]

Now the engine is running good with the pod filter, it only has a tiny flat spot in full throttle at low revs. I will put the 100mm tube between the carb and the filter to solve that.

I was thinking if the cb performance hi flow manifold will make any power increase with my 31 pict 3 carb. will put some single hd springs too.

Does anybody used it with the 31 carb?

As is right now, it runs faster that a 1303s superbeetle (wbx dj cam on it, 8x33 gearbox)

Mine has 8x35 gearbox, lightened flywheel, fully balanced, slightly ported and a tuck away exhaust

Aprox top speed is 150km/h
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[Alstrup]

[Albertoprop17]

[Albertoprop17]

Found a 34 pict 3 carb, I'm going to rebuild it and maybe increase the venturi size to 28mm in the future.

Current carb jets:

Main jet 130
Air correction jet 60z
Idle jet 60
Auxiliary fuel jet 47.5

Also I have an early air cleaner that I'm going to modify to act as a velocity stack and put a k&n style filter. The side of the housing will be drilled for max air flow
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