Distributor for Dual Weber 40's

[jaket3]

Hi,

I've currently got a stock 1600 DP engine in a 71 Karman Ghia.
It has a stock DVDA distributor.

Now I'm changing to Dual Weber 40's and a Vintage speed exhaust.

I'm assuming first that my stock DVDA distributor won't work. Is that right. Or can I use it (I guess I just block of the retard pipe?)

I've already got a Bosch SVDA from an 1600 Type 3 engine. Part number 311905205F

Any reason why that wouldn't be a good swap? I'm assuming type 1 and 3 distributors have a similar advance curve?

I can also get a 043905205B easily locally.

Or I've got a mechanical advance one with no part number. I think it's a 009 copy. But I took that off my Type 3 as it has a massive flat spot.

Any advice?

Thanks.

[Alstrup]

It depends totally on WHICH Weber IDF´s. Spanish have nowhere near enough vacum signal to pull avacum can. HPMX a.o. Chinese copies are a little better, but not good. They can be made to work, but that´s no job for the average garage mechanic. No offense to annyone. Just coming from a person who wasted 2 carbs before I learned to do it right.
That said, the type 3 distributor should be quite OK along with a modded carb.
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[BYeaton]

I had awesome luck with both an 010 and an 019 with dual 40's. I would steer clear from vacuum with those carbs.

[Glenn]

1600DP with 40IDF and nothing else... 019.
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Glenn
74 Beetle Specs | 74 Beetle Restoration | 2180cc Engine
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[jaket3]

Hi,

Thanks for the replies. They are Spanish Webers. So consensus is there is not enough vaccum to pull the advance that way.

So I'll pick a Mechanical advance distributor then. Presumably time to 30 degrees at full advance.

I'll try my Petronix one I have knocking around, and try to get a 019.

Thanks for the advice.

[mark tucker]

I would go with the cb magna spark with No execptions. and it's eazy to tune unlike the oe style junk that is built so you have a lot to do to recurve them.

[jaket3]

Hi,

Quick update.

I have the carbs installed and the exhaust. Big improvement in power even though it's not dialled in yet.

Carbs:
Dual Weber 40's (Spanish)
Main 115, Idles 55

Vintage Speed Sport Exhaust. Stock 1600 DP otherwise.

I've had fun with some terrible aftermarket distributors:

First one was a old 009 clone I had from my old Type 3. This is the one installed now. It actually runs OK (ish), but the advance is all or nothing around 3000 rpm. With a timing light increasing RPM does nothing up to about 2800rpm, then it jumps about 20 degrees by 3000rpm.

So unsurprisingly it feels a little flat then goes.

I then tried a new 009 clone. Advance is very jumpy, hit and miss. So sent that back.

Then I got another Kultek one, and that had a terrible spark. Hardly ran even though timed at 8 degree BTDC at idle. Maybe condensor was gone. So sent that back too.

Tried to find an 019 but no luck so far.

Anyway I think I'm done with trying with the cheap copies. And I'd really like a vacuum advance too. (But my Webers only have a weak vacuum).

So I was thinking of buying this: 123/TUNE+ 4-R-V-V (bluetooth)
https://www.123ignitionshop.com/gb/tune-plus-volvo/185-123tune4rvv-bluetooth.html

This looks to be ideal. I can set a 019 /009 style mechanical advance plus have a vacuum advance at light throttle even with my weaker Weber 40 vacuum.

It looks fairly easy to set up and future proof to some degree if I change setup.

Am I on the right track here? Anyone else had good results from this.

Thanks

Jake

[66brm]

Your idles are way too big, that's another reason for it being flat down low
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Aust. RHD 66 Type 1
Aust. RHD 57 Type 1 Oval

[jaket3]

[66brm]

Try the 50's they will be closer, but more than likely you'll end up at 47's. Just remember to make one change at a time, and retune the idle mixture after each change.
_________________
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Aust. RHD 57 Type 1 Oval

[slalombuggy]

First one was a old 009 clone I had from my old Type 3. This is the one installed now. It actually runs OK (ish), but the advance is all or nothing around 3000 rpm. With a timing light increasing RPM does nothing up to about 2800rpm, then it jumps about 20 degrees by 3000rpm.

This isn't a bad distributor, this is bad maintenance. Your weights are sticking and it needs to be taken apart and cleaned. IF it says Bosch on the bottom of it there should be a nice smooth advance.

brad

[jaket3]

[Alstrup]

The post 2018 123´s are OK as such. Nowhere near the finetuning options as with a Black box, Megajolt and similar, but it seems that most people can figure out how to adjust the 123 so the engine runs fair. That is about the only advantage it has apart from a decent build quality.

I aggre 55 idles are 90% certain too large.
PS. Wrt the 123 tune. If you are in doubt and/or have no experience in trimming ignition, you can always begin with one of the base setting which are in the program. I have noticed that many people simply stick to those because "the engine runs fine" That is not bad, but it can often get better
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[jaket3]

Hi,

Thanks all for the comments.

I will try again with my "serviced" distributor and see how it advances.

And I'll try 50 idle jets next too.

I'll post the results back here after the weekend!

Thanks

[jaket3]

OK had some time this morning.

Fitted the 50 Idle Jets and serviced the distributor.
So now it's
1600 DP Engine
VS Sport Exhaust
Dual Weber 40's
115 mains
50 idles
009 clone, timed to 30 degrees max. (8degrees at 900rpm)

It now starts to advance at 2000rpm, and is fully advanced at 3000.
I timed to it 8 degrees at 900rpm, which maxes out at 30 degrees at 3000rpm.

Went for a drive, warmed up reset idle mixture screws.

All seems good. Nice power, only very moderate flat spot at low rpm. Happy with that given lack of vacuum signal for now. I'd say it feels 95% there. Significantly better power than before and not needing to shift down as early on hills etc. Well worth the upgrade.

Only issue is the occasional minor back fire when letting off the throttle in 3rd and 4th. This is a bit better than it was on the 55 idles but still there from time to time.

After I reset the idle mixture screws the idle went up to 1000rpm. So tomorrow I'll reduce that and resynch and then reset the mixture screws. Maybe that's the what's causing the occasional backfire on letting up the throttle?

Other than that over a 15 mile drive round the hills it went really well. Really happy with progress.


Picture of engine bay and Ghia in scenery.


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[jaket3]

Update:

I realised my Khultec 009 clone had a dodgy condenser. Changed that and installed it and the advance is smoother and comes in a bit earlier that my other one. So that's my best distributor for now.

I had some 47.5 idles so I tried them too.

I think this is the sweet spot but not that much change from the 50's

On the 50's I was only out 3/4 of a turn on mixture screws. On 47.5 I am at around 1 turn out.

With the 47.5 the backfire on letting the throttle up has mostly gone. Only got it once on my latest test drive. More of a little pop, not a loud one.

Engine idles well and pulls nicely. Only minor irritation is that at really light throttle is hesitates, adding a bit more throttle sorts that out. For example in 3rd at 25mph, and slowly accelerating it's a bit flat. Once the revs pick up (Or I just press more on the pedal) it's fine. (It was the same with the 50 idles) That's different to the stock carb / distributor where it was very well behaved in that situation. Overall it's really driveable.

I'm concluding it's about as good as it will get without the vacuum advance. I might try the 123 tune and fit a vacuum line to the Weber's if I'm feeling flush in the New Year but for now it feels good enough.

Thanks for the help and advice. As usual the Samba rocks!

[oprn]

I played with distributors and modified vacuum pots to try and get a match for my 40 Webers. I am convinced it can be done with enough time and effort but it turned into a bit of a career. A couple fellows here convinced me to go crank trigger for the ease of tuning and Ya!, what would have taken weeks to accomplish with distributors was accomplished in a few hours and about 6 test runs.

Some would question the cost/improvement ratio. Fair enough, the mileage gain was about 3 mpg with the part throttle vacuum signal incorporated but the drivability was much better too. And it has been a zero maintenance system so far.

Sounds like you are close to ideal, maybe a bit more initial advance would help the off idle hesitation? It would be interesting to see what your fuel mileage is now.

[jaket3]

[Alstrup]

You cannot compare a 123 with a crank trigger or the Black box for that matter.
The 123 is merely an electronic SVDA at the end of the day, - with the option of making the mechanical side somewhat better though. The vacum side is very crude, but admittedly is good enough for even pro tuners (?)
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[oprn]

I used the Ford EDIS 4 wasted spark system that only requires a crank sensor (distributor drive is not used) and the Megajolt spark controller. The program for the Megajolt is a down load off thier site to your favorite laptop then you can create your own spark table. There are a few examples here on this site to get you started, I can give you a link to mine if you want. Anyone with basic hand tools and a timing light can install it. The Dub Shop is a good source for that brand. They market bolt on conversions.

There are other brands out there too. I picked mine up used from someone on this site at a cost that was equivalent to getting a good rebuilt German stock distributor.

Personally I would not spend big bucks to do this on a stockish engine as the gains are not that huge but a good used system at a good price is well worth your while.