Yeah, the final drive ratio on the bus is 5.373 to 1. Good for about 20 ft! I'll race but we can only use 60 hp, probably have to pull 2 plug wires in that Miata and I'd still lose.

Craig, great memories for sure. In 1971 I had a beater 1200cc 1964 bug. Every time I drove it was a race, the only time it wasn't floored was when it (finally) hit the speed limit. Never an easy minute. About 27 mpg and about 27 cents a gallon. Good times indeed.

Doorman, what fun that race must have been and to remember it after the only FEW years back to high school is fantastic. Steve's bus might beat the Miata in a short drag race, but I have had it up to 130 at red line so no top end challenge.

Steve your bus weight is 2800 I think the Miata is 3000,

Steve; Have a few suggestions. 1 get an oil temperature gauge as that is where a large portion of your cooling comes from, 2 if you have high oil temp, switch to a larger oil pump and a filter, next step would be to switch to the late fan housing and the "dog house" cooler (use stock parts here as they are better) or at the very least put a BIG (as in air flow) fan on your cooler. those muffin fans will not cut it in hot weather and the cooler has limited fin area. 3 fatten up your fuel with the open exhaust or you will be burning lean (air cooled's enemy) 4 a good vacuum distributor will greatly help the drive ability and also make it easier to avoid denotation. The late factory dog house setup is the greatest advancement for any working VW engine.

quote:

Originally posted by Steve VW:
Given the nature of "heating" system, I decided it was not worth fooling with it. When I drove the VW bugs in winter, all I got was a little heat on my left foot and I had to scrape the inside of the windshield to keep it clear!

As you said, this will hopefully be a warm weather toad. I replaced the exhaust heat exchangers with plain J pipes. The fan housing has no heat ducts to divert engine cooling air. If I ever need heat I will install something to run on propane. The old ones had gasoline heaters but I would not run those. Great when they worked but cranky.

This engine had been running really hot. Both heads were cracked, all four holes. The valve rocker arms were almost siezed to the shaft with coked oil residues. Cleaning them was like cleaning a barbeque grill... I made changes to improve cooling function air flow and relocated the oil cooler outside the fan housing.

Heat wave today, calling for 40 degrees. First time since Dec 4. Hope to get the tow bar brackets done this week.

John, thanks for the input. This whole thing is an ongoing field test anyway.

1/2- notice in photo, upper left: Oil filter, oil temperature sender and temp switch for fan.



2- If I have high oil temp, changes will be made.

Considering the teardown of this engine revealed extreme heat in the cylinder heads, I am not as concerned about oil cooling. The heads get a little oil from the block, a small amount flows up the hollow pushrods, through the rockers and drains back through the pushrod tubes. Not enough to do much cooling.

The heads are cooled by airflow from the fan. Anything that changes the air flow will affect the head temperature. The original VWs had the oil cooler in the fan housing, blocking flow to the left cylinders. The left side head temps could be 50 degrees or more higher. As a result, the early gearheads pulled that cooler and installed external coolers. This improved the temp balance from side to side.

As for me, I do not favor the doghouse coolers simply because they are still diverting the oil cooler air from the fan flow resulting in less flow to engine. My fan housing has no loss of air to oil cooler or heat boxes. I will install head temp gauge if needed. (The replacement heads I used can be used for Type 3s with fuel injection and have threaded bosses for CHT senders!)

If oil temps do get high, the cooler and fan will be modified.

3- I am not sure why the changes in exhaust would change the mixture ratio. Once the fuel is atomized, vaporized and mixed going through the carburetor, the fuel mixture will be established there. Barring air leaks downsteam, the mixture is fixed.

Changes in temperature will affect the density of the charge air/fuel mixture but not the ratio. Changes in air flow can affect cylinder scavenging and may affect charge density. Improving the induction and exhaust flow will result in better cylinder filling, the result being higher charge density and more fuel/air available to burn. The higher charge produces more power and therefore more heat. This is why turbos work so well, they jam the mixture in under pressure, ie higher density. This will indeed raise head temps but not from being lean...

The last time I ran VWs much was in the 70's but more recently I have about 900 hours operating air cooled 4 cylinder, carbureted Boxer engines with fixed timing and adjustable mixture control, ie Lycoming aircraft engines. There is much discussion in that crowd concerning CHT and EGT and mixture. Many operators have abandoned the former habit of running rich of peak to avoid detonation and cool a bit. With more modern temp monitors many are now running lean of peak in cruise...

4- There is much discussion on distributors as well. The aircraft Magnetos have fixed timing, run retarded and rich most of the time. Newer versions are running electronic igntions with advance, resulting in fuel economy improvements around 12%.

As for the VW, if it is run hard, ie throttle mostly open, there will be low vacuum and therefore minimal vacuum advance. Centrifugal advance will do if not too advanced. Only on part throttle high vacuum will the vacuum advance be effective. Depends on the driving habits, I guess. I will see how this setup works, might end up with both vac and centrifugal...

I will be able to drive it soon and get more feedback.

There was a time in my life when I had a 914 Porsche, when I looked in that mid-engine compartment all I could see was a mass of fuel and vacuum lines, scared me to death never ventured into that mess lol. I wish I had Steve as a consultant I might still have that car..

Dog house fans are larger, and the stock fan housing is more efficient than most after market ones (more sales volume to pay the engineers with) but your air flow system is in common use. Anything you do to a carbed engine to increase air flow requires enriching the mixture (an exception to this is the SU carburetor) Vacuum advance is used to give the engine more advance under light load and to take it away when heavily loaded. Weights are used to advance as RPM increases. personally use a 009 in a light weigh NA buggy (simple) but my turbo engines use a vacuum advance/pressure retard system. Back in the day when we put a engine in a bus- we always broke it in before turning it over to the customer and stressed never to use over 1/2 throttle for extended periods (long grades). Almost anything will work if you take it easy, but power produces heat and extended power produces vast amounts. Want to help not argue and I did not see the filter, sorry. john

Thanks for your feedback, John. It is obvious you have extensive experience with these things. Mixture, timing, compression, etc so many variables. Especially with the turbos things get spooky for sure.

(Back in the day I had a Judson supercharger on a 1200. Cranked it up to over 60 hp. Clutch slipped, would rev past redline real quick. Ran like stink, hot, and ate exhaust valves for lunch. Those were the days)

In this case I am trying to follow the KISS and make a very plain Jane toad setup. Given the extra heat problems with the bus engines I am just trying to get something that will be stable. As you point out, sustained high speed/output must be avoided. I do not see this as a long haul driver.

Did not intend to criticize your input. As I said this is a field test in progress, in the early stages.

It will be interesting to note the distributor changes, I still have the old vac distributor if needed. Still have to mark the crank pulley and play with the timing light to set max advance with the centrifugal one, then I'll find out what the idle will be...

I am in the process of designing an attachment for the tow bar. The front bracket plate attaches to 2 rails that span from the below the bumper back to the lower torsion bar tube. U bolts on the torsion tubes and brackets tie to the bumper mount points. Diagonal cross bracing horizontally and additional diagonal vertical braces from upper torsion tube to main rails. Hope to tie everything together to minimize load on the bumper. Photos to follow soon.

Please feel free to comment on my design/construction. I am flying a bit blind on this one. Maybe you've seen a bus with the towbar setup, that would be excellent.

49 degrees and rain yesterday, first thaw since Dec 5. Back down to 16 today, single digits tonight.

Here Ya go Steve!

530 HP Bus

I want one!

OMG that thing is insane.
I wonder how the driver gets out once the bus is in the truck? Must have to climb out the back...

I am having trouble remembering my VW Vans but, the 68 had two carburetors and I blew it up, thought I would rebuild the engine, but my skills were not up to the task, so I bought an engine from a junk yard. It had fuel injection, but I read somewhere the fuel injection of that engine type never worked correctly. So I took all the stuff from the old engine and put it on the junk yard engine. seemed to work fine I towed a bass boat all over with it, for several years. I keep thinking it was a 68 but it might have been a 71.

My poptop I think was an 85 and had a liquid cooled engine, I pulled a bass boat all over the country with it pretty slow going up a grade, and fast going down. Never had a real problem, but the engine did like to chug a bit at slow speeds, I think it was fuel injected, but I am not real sure.

I was not smart enough to know one should not tow a 3600 pound boat and trailer with a VW van. Surprisingly it even stopped pretty well, but my friends said the front end was pretty high when the boat was being towed.

Geez memories, I remember a trip from Dayton to the Ohio river on the West Virginia border. Going along I-70 to a bass tournament. Travelling with several other guys going to same tournament. My friend in a big ole Dodge pickup, thought it was great fun on the hills to pull in front of me with the VW and slow way down going down a grade so I could not build speed for the next upgrade, I would be down to like 15 mph by the time I crested the grade. He would get behind me, and do the same thing next grade.

I am still amazed that I got home (Wisconsin) from Alaska in a 1961 VW bug. The Alcan Highway in those days was 1200 miles or more gravel. I left there in the approaching winter, had to flip the rear wheels around to put tires chains on. Pulling a trailer running thru 4-6 inches of snow.

The entire rig (trailer and VW) weighed 4000 lbs, People running down the highway labeled it "6 wheels and a ball of mud"! I don't think I ever got into 4th gear until I got into the lower states. Even then it was either very flat or down hill running.

I started laying out the towbar location with some wooden pieces. The front bracket will be under the bumper:



The main frame straps go back to the lower torsion tube.



There will be numerous cross braces to go. Also some diagonals back to the upper torsion tubes.



I had to order some bigger U bolts for the real towbar, so I started on the wiring projects. I have to install gauges and the trailer lighting harness.

Looking at the panel I decided the ancient AM/FM cassette player could go. The hole is big enough for gauges, but the recess was too small for a recessed plate.



I cut a small wooden cover plate. Mounted the gauges and they fit right over the hole.



Oil pressure, oil temperature, digital voltmeter.
The switch will turn on the oil cooler fan manually. (There is an automatic temperature switch already installed.) To the left of the switch will be an LED indicator for the cooler fan



I have to run wires and pressure line from the engine to the gauges. When I finish the gauge job I will tap into the fuse box circuits for the tail lights and running lights and run a harness forward to the tow bar.

Nice project. Found something you just got to have. https://cosprings.craigslist.o...-pit/6427216201.html

Looks like SteveVW has finished his toad:

https://imgur.com/7FkErqa