TheSamba.com :: View topic - distributor and engine compatibility and timing

Fri Jul 28, 2017 8:57 am

It was a dark and stormy night. The rain lashed at the windshield as the wind lifted her red skirt just enough to….

So, my question concerns distributor compatibility. I know there are lots of discussions on distributor and carburetor compatibility, but can there also be an issue with distributor and engine compatibility especially as related to timing?

In a nutshell, I have an engine that originally called for a distributor that should be timed to 0d TDC.
However, I inherited a distributor that is supposed to be timed to 7.5d BTDC.
So, here’s my specific questions:
1. Which timing should I use? 0d TDC or 7.5 BTDC?

Background:
• I have a 1968 Ghia Convertible, Engine#: H5551806 "H5" = Type1, 1968-69 1500cc 44bhp DIN, 53HP SAE M157 USA/Canada. Single Port, Rebuilt in 1998 by GEX (I know, I know…I’m still finding metal shavings in the oil)
• Distributor: “Jur 4, 0 231 137 011, 131-905-205" stamped on side of distributor (no letter next to the “205”)
• Solex 30 pict 2 Carb
• Engine runs fine but never seems to have much power or acceleration, especially compared to my stock ’71 Ghia.

According to Old Volks Home, MY DISTRIBUTOR matches this vehicle:
o Bus & Pickup 1966-1967 * 1500 Timing Set At:: 7.5deg BTDC Static or @ 800-950rpm
o Distributor: VW 131-905-205, Bosch 0231 137 011 > 315-905-205B, 0231 137 031
Can Use: VW 113-905-205K/L, Bosch 0231 137 009/010, 113-905-205M, 0231 137 021, 113-905-205T, 0231 137 035 or 036

However, if I reference Old Volks Home for MY ENGINE, it shows the following distributors:
o Beetle 1968 * 1500 Man Trans Timing Set At:: 0deg TDC Static or @ 800-950rpm
 Distributor: VW 113-905-205M, Bosch 0231 137 021
Can Use: VW 113-905-205T, Bosch 0231 137 035 or 036

Note: there is no match of distributor numbers.
Note: There is also incompatibility with the timing, i.e. 7.5d BTDC vs 0d TDC.

So my second question is:
2. Do I need to replace my dizzy with one that is compatible with my ENGINE?

Finally, my engine doesn’t seem to have very much power. I have recently done a complete tune up, but nothing seems to help. I have noticed that my SVSA vacuum-advance-only distributor seems a little anemic as far as advancing. i.e.

Timed at 7d BTDC @ idle (vac hose disconnected & plugged)
(at idle, there is no change in timing with the vac disconnected vs disconnected/plugged)
Timed at 17 BTDC @ 3k rpms, using an advance timing light. (vac hose connected)
(at 3k rpms, with vac hose disconnected, there is no advance at all)

Tune up:
Valves .006 all around, stone cold
New Dist. Cap and rotor – Bosch
New Condenser – Bosch
New Points (dwell = 46),
Plugs looked great
Plug wires look fine, but not replaced recently
No debris in the fuel filter.
Solex 30 pict 2 Carb has nice strong squirt from accelerator pump
Finally adjusted the idle= 880 RPMs at the carburetor. (although the idle readings jump all over the place)

Note: I’m getting a whopping 10d advance change out of this distributor.
If you look up my dizzy 131-905-205 using this source, it says I should get a max advance of something like 25d.
https://www.thesamba.com/vw/archives/manuals/Bosch_Tune_Up_Parts/Bosch_Tune_Up_Parts.pdf

So my 3rd question is:
3. Is 10d advance normal/acceptable and if not, does this mean my dizzy is toast or could it just need some cleaning/lubricating? (I don’t have a vacuum gauge)

Ok, sorry a 4th question:
4. If I need to replace my dizzy, what and where should I buy?

Thanks “in advance” for all responses.
Dwight

Fri Jul 28, 2017 9:36 am

Since you've been reading you already know that distributor matching is all about your choice of carburetor not your engine. The three components that you listed are all very close in factory age but not a perfect match.

The 30 PICT 2 carburetor and the 131 905 205 distributor are not a match. You will need to change to a 113 905 205 M or T distributor. or, you could change to a 30 PICT 1 carburetor and keep the 131 905 205. You shouldn't expect any advance out of a vacuum only distributor if you plug/unplug the lines.

The metal in your oil might explain your lack of power but so would only 10 degrees of advance.

Q1: no, there is no relation between engine distributor and timing on early air cooled engines.

Q2: no, you need to match carburetor and distributor the engine is irrelevant. The oldvolkshome website gets confusing with all the interchange information. I much prefer this:

https://www.thesamba.com/vw/archives/manuals/Bosch_Tune_Up_Parts/Bosch_Tune_Up_Parts.pdf

Q3: the fact that you are only getting 10 degrees or 17 means that no amount of tuning is going to resolve your issue . That distributor should be delivering around 25 degrees of advance.

Q4: Buy a restored correct original German distributor from one of the restorers in the classifieds on this site. they are your fellow hobbiest's.

Fri Jul 28, 2017 11:00 am

I'd personally buy a restored 113905205M or T distributor for your application. Both were used with the Solex 30-2 carb. I run a restored T distributor w/a brand new NOS Bosch vacuum canister with my restored Solex 30-2 carb. It's works beautifully.

As Tasb stated, get a restored one from us that restore them.

Fri Jul 28, 2017 7:09 pm

If you know someone locally you might see if they can curve your distributor. This way you get some exact information about it.

Match that to an existing curve to determine if your distributor is functioning correctly. Also check to make sure the distributor you have is correct for your engine.

Once you have done that you have at least a few options:

1. Rebuild your distributor
2. Have someone else rebuild it
3. Buy one from someone

You should be able to find everything you need here.

Mon Dec 17, 2018 11:34 pm

tasb wrote: Since you've been reading you already know that distributor matching is all about your choice of carburetor not your engine. The three components that you listed are all very close in factory age but not a perfect match.

The 30 PICT 2 carburetor and the 131 905 205 distributor are not a match. You will need to change to a 113 905 205 M or T distributor. or, you could change to a 30 PICT 1 carburetor and keep the 131 905 205. You shouldn't expect any advance out of a vacuum only distributor if you plug/unplug the lines.

The metal in your oil might explain your lack of power but so would only 10 degrees of advance.

Q1: no, there is no relation between engine distributor and timing on early air cooled engines.

Q2: no, you need to match carburetor and distributor the engine is irrelevant. The oldvolkshome website gets confusing with all the interchange information. I much prefer this:

https://www.thesamba.com/vw/archives/manuals/Bosch_Tune_Up_Parts/Bosch_Tune_Up_Parts.pdf

Q3: the fact that you are only getting 10 degrees or 17 means that no amount of tuning is going to resolve your issue . That distributor should be delivering around 25 degrees of advance.

Q4: Buy a restored correct original German distributor from one of the restorers in the classifieds on this site. they are your fellow hobbiest's. hi i have a 30-2 carb and a 133 905 205k dizzy are they a match ?? cheers fish ..

Tue Dec 18, 2018 4:17 am

nz fish wrote: hi i have a 30-2 carb and a 133 905 205k dizzy are they a match ?? cheers fish ..

Yes, a 113905205K and 30-2 distributor are a good match. The 205K times at 7.5 BTDC if it has it's correct vacuum can.

Tue Dec 18, 2018 6:34 am

They aren't a factory match but as Bill stated, can be made to work together with proper timing.

Fri Dec 28, 2018 9:11 am

I must apologize for letting this thread (that I started) lay fallow for so long. I really appreciate everyone’s advice and have acted upon it. I hope it has helped other readers as well.

As a result of this advice, I bought a very nice rebuilt distributor from “tasb” (Tim Barany) see pix. It worked perfectly and solved all my sluggish engine problems. I now get 35d of advance and the car runs great.

So in summary, my setup is now:
• Solex 30 pict 2 Carburetor
• 113 905 205 T SVS Vac only Distributor
• Timed at zero degrees TDC at idle (750 rpms) vacuum hose disconnected and plugged
• Timing advances to 35d at 3K RPMs with vac hose connected.
• Dwell at 51
• Points at .016

I also relied on these sites:
Distributor versions explained with pix:
https://www.wolfsburgwest.com/wolfsburg_new/electrical/electrical_common/distributors.cfm

OldVolksHome.com – “Distributor Parts and Specifications” and also - “Distributor Interchange Bosch To VW Number”:
http://www.oldvolkshome.com/

Note: the oldvolkshome site is currently down (bummer) but info is available at:
https://web.archive.org/web/20170811040030/http://www.oldvolkshome.com:80/ignition.htm#A5560

Choosing the Right Distributor for your VW: http://www.aircooled.net/vw-distributor-options/

Bosch – VW Distributor Information -Tune-up Part Numbers:
https://www.thesamba.com/vw/archives/manuals/Bosch_Tune_Up_Parts/Bosch_Tune_Up_Parts.pdf

How to check a vacuum advance unit on a distributor: https://www.youtube.com/watch?v=AeZKZZ0_n_4

Tune-up procedures: http://www.vw-resource.com/tune_up.html#distributor

Hope this is helpful and thanks again for everyone who pitched in to help me. I have learned so much from my fellow Samba-ites.