New guy with a 1970 Ultravan classic RV

[ron]

I just saw on of those ultravan out side of town this week with weeds as high as the windows. I think I will check it out.

[SoobieOut]

Welcome to Ecomodder.

I saw one of the corvair powered motorhomes in excellent condition at the Barrett Jackson car auction last January. It sold for $1800!! I kicked myself for not sticking around to bid on it.

Reminds me of an airstream camper with a drivetrain.

[larryforman]

Actually, this is not a lock up torque converter. It is one of the standard torque converters with a given torque converter vane angle. What the switchable torque converter does is simply switch from a mid-angled torque vane to one that goes from min to max torque vane angle. There is not change from a non-lockup torque converter. Thus you can dash select from a higher rpm for one torque value to a lower rpm for a different torque value. Thus it functions like a half overdrive reducing rpms for highway use and higher rpms for more torque when starting out. Not a huge difference, but it might help reduce mileage.

[slowmover]

The famous "switch pitch". Made for some high compression rocket ships from GM for a few years. Sad it was never fully developed. But it made for some damn fast Buicks!

[War_Wagon]

Originally Posted by Frank Lee

Dry weight 3-4000 lbs; touring weight 4500-5800 lbs.

A Buick Park Avenue's curb weight can be 3800 lbs. They have lock-up converters. Come to think of it, full-size pickups do too.

Yup they sure do, but in those setups they are controlled by the car's ecu. As soon as the throttle gets pushed passed a certain point or the load increases etc the converter unlocks. But in this case it would be operated by a toggle switch, so like I said if it was only engaged on the flats at cruising speed it should be fine, but as soon as a situation arose when a factory equipped lockup would disengage, but this one was left on, it could do a lot of damage.

But none of this matters as apparently it isn't a lock up converter. I didn't know anyone made switch pitch converters anymore, so as far as OP getting his money back in fuel savings after installing one, I would think that the part time 200 RPM lowering of stall speed would not be the most helpful thing to spend that money on. Since this rig doesn't have an overdrive anyway, at highway speeds it is probably already turning at an RPM that is above the stall speed (assuming current stall speed is around 1500-1800 given the engine its attached to), so if cruising RPM is say 2200 RPM, this converter is already as "locked up" as it's going to get, so lowering the stall speed at this point won't do anything. I see the advantage of having a higher stall speed in town in order to get it moving, then switching to a lower one for the highway, but as far as it acting as a "half overdrive", it would totally depend on your usual cruising RPMs and where your current converter stalls at.

[OwenKS]

Originally Posted by Frank Lee

Dry weight 3-4000 lbs; touring weight 4500-5800 lbs.

A Buick Park Avenue's curb weight can be 3800 lbs. They have lock-up converters. Come to think of it, full-size pickups do too.

I wonder why this one weighs 7000 lbs when the Ultravan site says what I quoted above?

If a little Corvair engine can move that thing down the road, I'm sure a nice GM 3800 engine/trans combo with OD and locking converter would move it down the road even more nicely, and who knows, maybe it could break into the 20's mpgs.

Frank, the numbers you are quoting are for the Corvair powered Ultra Van. Ultra, Inc. also built 50 Ultra Vans powered by a 307 cid small block Chevy V8. These coaches are about 1,500 lbs heavier due to the drivetrain and necessary structural beefups. Larry's coach is one of these heavier ones. Also, the Toronado drivetrain conversion in Larry's coach is significantly heavier than OEM.

In fact, Larry has chopped about 1,000 lbs out of his coach since the first time he used it, but it still remains one of the heaviest Ultra Vans on record.

[ron]

I am going to town today and will swing by the air port area and see if the Ultar is still there , and if it is infact one.

[OwenKS]

Originally Posted by ron

I am going to town today and will swing by the air port area and see if the Ultar is still there , and if it is infact one.

If you take pictures I should be able to help you identify the coach number, and find the owner.

[ron]

I am going to take the camera and will have my son show me how to get them loaded ,(I can type on this thing and thats about all)

[ron]

Im back but with bad news, the Ultra is gone! it only sat there for 15-20 years and when Im interested POOF. I think that the old boy passed because the place is all cleaned up now. On a better note I just recorded my best trip mpg in my techoma 50 mi. 23.9 instant mpg. Reading on 1/2 tank 172 miles so far.