LiMBO - Late Model Bus Organization, International

Technical forums => Modifications and Alterations => Topic started by: dmartin on January 01, 2008, 06:35:42 PM

Title: Mods to move family of eight uphill
Post by: dmartin on January 01, 2008, 06:35:42 PM
Here's a honkin hello from my family here in northern Vermont. :D I bought my currently stored 1981 Vanagon on eBay for $1000 (my first Vanagon rusted out and I sold it to a Hippywannabe for $1500). The family got out the sandpaper, and I painted her Regal Red with a cream top - came out beautiful for $7.99. We ran it four summers and it started exhaling blue. I knew I could rebuild the engine since I rebuilt my last Vanagon's engine 11 years ago with great success. So anyway, the kids are all bigger and I felt the need for more power  8) , but not necessarily speed. I've grown up quite a bit and have tired of the snappiness that is so characteristic of Jettas and other liquid-cooled conveyances. Why not tick off the tourists up here and do the speed limit? So to get her done, I tore into the job last spring. But this time I changed a few things. I added a balanced/counterweighted crank and new GEX heads with larger valves. I also junked the 94mm scuffed pistons and jugs, replacing them with new 96mm ones. The GEX guy told me my fuel economy would drop a little, but after running it all last summer it went up about 1mpg to 21 (of course this is running around town with kids and groceries, mixed with the 8 miles of highway to town, and also the mile of gravel - uphill - to get home).  My wife and I went to a sawmill seminar at Woodmizer in Maine and got 24mpg one trip without the kids.

At present, with the mountains of snow we have everywhere up here, I'm dreaming of getting the bus out once sugaring is done. I got an "electric turbocharger" on eBay and have it connected in before the air filter box - I just removed that 90 degree snout and clamped in a short length of 3" dryer duct. I need to rig up an electric switch to the throttle body so the fan kicks on when I'm just starting to go uphill. Anyone out there try this before? It's supposedly going to get me about 2psi of boost - maybe better fuel economy, and definitely more power. With six kids (eight when the Fresh Air kids are here  :shock: ) we wanted a little more than my engine mods gave us on the rebuild - the mods sent us from the stock 67 hp to just above 80 (GEX's guess). That doesn't sound like much, but I've noticed many hills around here that I no longer need to downshift on! Happy trails one and all!!!!  Dan Martin
Post by: Vanagonjr on January 08, 2008, 12:48:16 PM
Good to hear about your happiness with the Air cooled Vanagon.  I have not tried the "electric turbocharger", but I kinda doubt that it will do anything.  For one, it is taking power from the engine to run it.  But I guess one could say the above about a supercharger!

With a turbo, the exhaust gas is already going out, so there is some real gain there, without a taxing effect on fuel ecconomy.

Hope the GEX stuff works out for you, (sounds like it has)  they have a real bad reputation, at least as an engine re-builder.  Your better off doing your own re-build vs. buying one from them.  I've also rebuilt an air cooled Vanagon engine and other than ahving 67 Hp when finished, it was really enjoyable.  

Boston Bob, a LiMBO member, is reportedly a great source for big-valve heads (or complete engines)-check him out next time!

John R
Post by: dmartin on January 11, 2008, 08:06:52 PM
Yes VanagonJr, it sure gives you a feeling of self-worth when a VW rebuild that you've worked so many hours on purrs to life. On this last rebuild I ran into a problem with the counterweighted crank from GEX. I was turning things over as I tightened the crankcase bolts and thought all was OK. But when I torqued the flywheel bolts (5 of them) and then rotated the crank, something inside came to a stop. After some fancy optical configuration involving a flashlight and a small mirror, I could see that the crank counterweight nearest the flywheel was hitting the inside of the case! I split the case and ground off some aluminum, cleaned out the alum. dust and reassembled. All was OK again until I went to start the engine in the Van. I could only get it to backfire and smell of gas. After thinking it over for a week or so, I checked the distributor driveshaft - off 180 degrees! The distraction of the crank was all it took to turn my brain into jelly  :shock: . One other thing: I didn't check tolerances/clearances on the valve stems in the refurbished GEX heads, but from what I remember about the heads I rebuilt myself 10 years before on another engine, the GEX ones seemed a little loose. I should have checked when I had them apart to clean them. It doesn't seem to burn any oil, so I guess I'm set for a while.

As far as the "electric turbo" goes, I'm just hoping the CFM of the fan exceeds the CFM requirement of the engine at say 4000 rpm? I guess it's easy enough to figure: it would be 4000rpm x 2.08 liters/rev x 1000cc/liter x  1inch cubed/2.54 cubed cm cubed x 1 foot cubed/12cubed inches cubed. This would give about 294 CFM. I'm not sure what the fan is rated for, but 300 sounds familiar. I guess maybe if there is any boost it will occur at the slower RPMs.
Post by: Vanagonjr on January 12, 2008, 09:47:49 AM
I would love to re-build another engine.  I almost was going to do a   Porsche 6 for my air cooled, when my friend on the west coast called and made me a deal on an 87 Westfalia weekender that I could not refuse.

My friend had plenty of Porsche stuff and that's the only way it would have made financial sense - based only on his generosity.   6 carbs are expensive though - even for a rebuild kit it is sky high!

I've thought of buying a $25 bug engine just to tinker with - but I should get my spare water boxer down cellar to play with, but it's just not as simple and fun as an air-cooled and I'm sure you know what I mean.

Still, it would be a great way to get a better understanding and challenge myself.