Brosol h32/34 pdsi carb

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Blacka1vw
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Brosol h32/34 pdsi carb

Post by Blacka1vw » Wed Jul 15, 2020 3:01 pm

New member here. I’ve been searching trying to find any information on the Brosol h32/34 pdsi carbs. I’m wondering about initial set up and tuning. Thanks
1971 Vw beetle
1971 Vw super beetle
1973 Vw Bus
1979 VW Bus
1985 Vw Cabriolet

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Amskeptic
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Re: Brosol h32/34 pdsi carb

Post by Amskeptic » Sun Jul 19, 2020 7:22 pm

Blacka1vw wrote:
Wed Jul 15, 2020 3:01 pm
New member here. I’ve been searching trying to find any information on the Brosol h32/34 pdsi carbs. I’m wondering about initial set up and tuning. Thanks
Initial set-up will be found in the '67 and earlier Type 3 manuals. The factory buses use PDSIT carbs which have a central idling circuit grafted on the left carb that routes down to the intake manifolds. That tuning process is described here:

https://itinerant-air-cooled.com/viewto ... =50&t=7767

You CAN use the air synchronization and fuel synchronization procedures in the above article for the PDSI carburetors, but adjust the mixtures to best idle.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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Re: Brosol h32/34 pdsi carb

Post by Blacka1vw » Mon Jul 20, 2020 5:21 am

Thanks for the reply. This site is incredible and I really appreciate the information that’s available on here and I love what you guys are doing. Gotta get in line for a home visit. I have been studying the above procedure as well as the Bentley and the ratwell. Comparing my carbs to the procedure. I think I got a game plan. I have the later dual carb linkage I believe. It uses the adjustable rods on both ends. A few other things got me kinda puzzled too. In the procedures for the pdsit carbs I read about setting the throttle plates choke open and also a choke closed setting. The new carbs don’t have the adjustable link between the choke and the throttle plate it’s just set so not much adjustment there on the choke open setup Bentley says adjust gap and secure the stop screws with caps I’m not sure what screws it’s referencing. I have a set of 32/34pdsit and the h32/34 pdsi carbs here that I’m studying. Setup will be going on a 1700 stock motor in place of the center mount. More to come...
1971 Vw beetle
1971 Vw super beetle
1973 Vw Bus
1979 VW Bus
1985 Vw Cabriolet

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Re: Brosol h32/34 pdsi carb

Post by Blacka1vw » Fri Jul 24, 2020 9:24 am

After more searching I found this
https://www.thesamba.com/vw/forum/viewt ... sc&start=0
It’s mostly type 1 but I believe it’s still useful. The new Brosol carbs I have are set up with the 22mm Venturi. I’m gonna go through my worn out 32-34 pdsit carbs and see what mains and Venturis are inside. Possibly come up with a combination that will be good for stock 1700
1971 Vw beetle
1971 Vw super beetle
1973 Vw Bus
1979 VW Bus
1985 Vw Cabriolet

69doublecab
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Re: Brosol h32/34 pdsi carb

Post by 69doublecab » Sun Nov 15, 2020 1:10 pm

Blacka1vw wrote:
Fri Jul 24, 2020 9:24 am
After more searching I found this
https://www.thesamba.com/vw/forum/viewt ... sc&start=0
It’s mostly type 1 but I believe it’s still useful. The new Brosol carbs I have are set up with the 22mm Venturi. I’m gonna go through my worn out 32-34 pdsit carbs and see what mains and Venturis are inside. Possibly come up with a combination that will be good for stock 1700
Perhaps it should be mentioned: CB performance lists some bigger venturis for the Brosal carbs.
I look at these as a great step forward to a good running, simple engine.
I once built a 912E clone from a 1967 Porsche 911. The owner wanted a daily driver for his wife.
I used a 1800 bus motor, had a machinist bore out the venturis about 3mm. If the stock motor made 68 hp, this might have made 78hp. With the stock A,F,M, S,X gearing in the 901 5 speed, this motor performed pretty well. I drove it the 300 miles to return it to the owner in Kansas City. (Wonder where it is now... still have the 911 motor!)

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Re: Brosol h32/34 pdsi carb

Post by Blacka1vw » Sun Nov 15, 2020 2:44 pm

69doublecab wrote:
Sun Nov 15, 2020 1:10 pm
Blacka1vw wrote:
Fri Jul 24, 2020 9:24 am
After more searching I found this
https://www.thesamba.com/vw/forum/viewt ... sc&start=0
It’s mostly type 1 but I believe it’s still useful. The new Brosol carbs I have are set up with the 22mm Venturi. I’m gonna go through my worn out 32-34 pdsit carbs and see what mains and Venturis are inside. Possibly come up with a combination that will be good for stock 1700
Perhaps it should be mentioned: CB performance lists some bigger venturis for the Brosal carbs.
I look at these as a great step forward to a good running, simple engine.
I once built a 912E clone from a 1967 Porsche 911. The owner wanted a daily driver for his wife.
I used a 1800 bus motor, had a machinist bore out the venturis about 3mm. If the stock motor made 68 hp, this might have made 78hp. With the stock A,F,M, S,X gearing in the 901 5 speed, this motor performed pretty well. I drove it the 300 miles to return it to the owner in Kansas City. (Wonder where it is now... still have the 911 motor!)
Good to know there are options available.
Probably somebody’s baby!

I’ve got a few thousand miles on them now. 1700 cb engine very mild cam. I tried a few different combos with the one bigger vent set I had available but the Bus seemed to run best with the small vents sold with the carbs 135 mains and the solenoid idle jets also from the stock Bus carbs. So far they have treated us really well. We’re getting 18 or so mpg. I’m collecting the pieces for a stock air box set up with pre heat hopefully for next season.
1971 Vw beetle
1971 Vw super beetle
1973 Vw Bus
1979 VW Bus
1985 Vw Cabriolet

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Amskeptic
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Re: Brosol h32/34 pdsi carb

Post by Amskeptic » Tue Jan 12, 2021 10:18 am

Blacka1vw wrote:
Sun Nov 15, 2020 2:44 pm
Bus seemed to run best with the small vents sold with the carbs 135 mains and the solenoid idle jets also from the stock Bus carbs. So far they have treated us really well. We’re getting 18 or so mpg.

Preach it ... people can get lost in sizing "bigger is better" but the engineering of airflow sometimes requires v-e-l-o-c-i-t-y to help atomize fuel, and that means smaller can be better!
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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Re: Brosol h32/34 pdsi carb

Post by Blacka1vw » Wed Jan 13, 2021 5:39 pm

It seems really happy with this current set up. The electric shutoff jets were a must. I’ve never drove another type 4 powered bus for comparison but it seems to have great power. I’m considering these carbs in a type 3 configuration for a 73 non walkthrough bus with a type 1 conversion We are hopefully bringing back from hibernation this spring. It was drove here to Pennsylvania from Guatemala and parked at a farm 10 years ago. Salt on the roads here is a drag. Hopefully only a few months now until the vws can come back out. Waiting anxiously!
1971 Vw beetle
1971 Vw super beetle
1973 Vw Bus
1979 VW Bus
1985 Vw Cabriolet

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