Building a Stock ish Type 1 engine for the 1971 VW Bus?

[Danwvw]

Yeah, I know! The stock exhaust could just make this little engine run hot, especially with the W-100. Another reason to re-think the cam! I am not opposed to the Idea of re-thinking this engine with a different cam, say One of those mild ones like the Web-Cam 86 then I could keep this nice quite exhaust system. Suppose I won't know anything about how the engine would perform in the bus until it's in the bus. Something I find too daunting a task at the moment.

Thanks "Tcash" good point. I will check the distributor with the strobe and I think what is going on with the Zenith carb idle fast is related to it's throttles are a little messed up or it could be that old rusty iron base where the butterflies seat. It does not want to return all the way without a little extra force.

Hay so I just had an epiphany on how to do the preheat: I just happen to have this thing in the photo below laying around, I could get a 69 bus Oil Bath stock air cleaner with the heat control valve that works with it and the cable etc... (The original 1971 air cleaner I have has a bad "Wax Pellet thermostat")

As for heat riser tubes Almost don't need them, at least not in our (almost never freezes) climate here on the Southern Oregon coast. Will get tubes though and use the small hole gasket. Which side does it go on?

69 VW Bus Thermostat Flap with the Pre-Heat control lever.

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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[Danwvw]

[Danwvw]

Just wondering about the Venturi size? Can't find a reference anywhere on 25mm Zenith Venturi's!
So The venturi's in this carburetor measured 25mm but are not marked. I did take them out to measure and used dielectric grease on all of the screws giving this old carb a bit of a cleaning but re-sealed it with it's old gaskets, old accel pump, hard O rings and Permatex High Tack on the base and top gaskets. (I Plan on rebuilding it once the jetting etc. figured out).

So How about total flow on an engine, Single carb configuration flow vs duals? Looked up the Zenith on the flow chart Carburetor Airflow Comparisons for the VW. When a single carb is used vs duals, does the actual flow increase due to both barrels working in tandem as my RaceTrim intake manifold plenum joins both barrels together? Is there too much flow? Probably why the small Venturi sizes work better!
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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[borninabus]

what i can tell you is that intake velocity is important and a bus needs as much as it can get.

the 25mm vents could be homemade (24s opened up on a lathe) or the 25mm vents came on porsche "super" models.

not much book science behind it, but i speak from experience:
get a good header, the right vents and jets and be done with it
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88 Van WBX, A/T - 13 JSW TDI 6M/T - 2012 Touareg TDI Sport

[Danwvw]

Heat risers installed.
Manifold operating at 132' and climbing,
Heat Riser incoming 435' and climbing,
Heat riser exit side 170' and climbing but just a little.
I'm probably going to need to mix the incoming air properly to stop the climbing temperatures. Also I am going to need a choke cable or servo actuator of some sort to the enrichment valve so it will start.

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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[Alan Brase]

Uhhh. Under normal circumstances, your air cleaner would have thermostatic control for the inlet temperature (68-71 used a cable slaved off the engine cooling thermostat, 1971 had its own self contained bulb in the snout of the air cleaner.
While I must say I'm a great fan of the 1971 oil bath air cleaner, I doubt you're gonna plumb one to that monster Vergasser you have there now.
Not sure how you preheat the air. Old Porsches had a pretty elegant, low tech way with the butterflies and nozzles directing a bit of waste cooling air at the air cleaners.
But I really think perhaps it is time to do more testing with a load and in the vehicle. I think the results you are getting now are not under load (unless that is really a dyno hooked up.) Further the dynamics of air flow and vehicle movement are gonna make a big difference. So, put it together and drive it!
Getting accurate temp measurement will be harder , but the proof is in the bottom line, so to speak.
If it shows poor driveablity, then perhaps a remote reading temp gauge might help.
(I recently bought a Chinese Digital combo VOM and clamp meter (amps AC)
And low and behold this thing has a cable and a tiny temp probe. Just checking on a water heater it seemed to be pretty sensitive.)
So, they are out there- remote reading temp gauges.
Al
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Al Brase
Projects: 67 sunroof bug, 67 Porsche 912 Targa, 70 Westy
Dec 1955 Single Cab pickup WANT 15" BUS RIMS dated 8/55, thru 12/55
To New owners: 1969 doublecab, 1971 Dormobile
Vanagons:
80 P27 Westy JUL 1979, 3rd oldest known US
83 1.6TD Vanagon, 87 Wolfie Westy daily driver, swap meet home

[Danwvw]

It's going to be a while before this engine goes into the bus! About all I can do now for comparison would be to check manifold temperatures again with the hot air hose disconnected from the top of the Zenith and see if the manifold temperature keeps climbing that way. Yeah, it's No load. Just a turn in on the throttle stop screw rev's it pretty good.

For sure need to figure out the plumbing. Maybe a plumbing rubber boot! http://www.hps-siliconehoses.com/hps-2-3-8-2-9-16-60mm-65mm-reducer-coupler-silicone-hose-blue.html Or just replace the intake hose with some 60mm flex hose. But that would look pretty bad with tape and all to make it fit.
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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[borninabus]

i used a plain rubber boot from home depot to modify my stock intake elbow.
cut it up, and epoxied on. holding up fine.

i also made some modifications to my oil bath to flow enough air for the zenith.
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88 Van WBX, A/T - 13 JSW TDI 6M/T - 2012 Touareg TDI Sport

[Danwvw]

Thanks "borninabus I just may do that too. Here is the updated build sheet and carburetor jetting info.

[Danwvw]

I just saw an ad today on the samba for a Porsche industrial engine that was in a bus and it's got a Zenith on it with the manifolds they used in 1959.

good running porsche 356a industrial engine Price: $4500

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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[Danwvw]

So here it is as it sit's Now! I am going to need two cables, Throttle and Choke. And without making a big deal out of this, Is there a way to run them both through the throttle cable route through the bus and then perhaps sheathed throttle cables over the top of the fan shroud? Or Cable and Sheath or something?

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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[borninabus]

your enrichment valve is installed upside-down.
and the lever is installed double upside down.

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88 Van WBX, A/T - 13 JSW TDI 6M/T - 2012 Touareg TDI Sport

[Danwvw]

I was wondering how the cable housing support was supposed to work the way it is!
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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[Alan Brase]

I might have mentioned before, buses till about 1960 had manual chokes, so a VW part exists that is about the right length. It was installed on the seat pedestal and shot back parallelling the shift rod, kinda.
Al
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Al Brase
Projects: 67 sunroof bug, 67 Porsche 912 Targa, 70 Westy
Dec 1955 Single Cab pickup WANT 15" BUS RIMS dated 8/55, thru 12/55
To New owners: 1969 doublecab, 1971 Dormobile
Vanagons:
80 P27 Westy JUL 1979, 3rd oldest known US
83 1.6TD Vanagon, 87 Wolfie Westy daily driver, swap meet home

[Danwvw]

Oh, Yeah, I remember that knob. I will look into doing it that way with one of the sheathed cables perhaps.
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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[Danwvw]

PICT 34 vs Zenith.
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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[Danwvw]

[Danwvw]

Regarding Pump Jet Orings on the Zenith NDIX 32 Carburetor

[volksnhousin]

I was browsing through your engine builds and enjoyed looking at things… I thought I would share a few thoughts I have about this engine.

If you keep the Zenith, a better flowing exhaust would probably be good. If you go stock carb you can probably get away with stock exhaust.

Perhaps installing 40 horsepower 1:1 ratio rockers would help the Engle 100 idle situation. Stock 1600 rockers are 1.1:1. Stock 40 hp rockers are 1:1… 40 horse rockers would make .037” less valve lift. .420 - .383 = .037 This might be something you want to try before installing a different cam.

Anyways, just some thoughts. Nice job on the engines and information. Have fun.

Andy

[Danwvw]