[401bluebird]

I found this thread from some time back this morning. I followed with interest when discussing driving in heavy haulers with the V6s, as I have a 1960 GMC 35' motor home conversion All-American bluebird Coach with a Clark 5-speed trans behind the original 401 V6 engine.

I drove it quite a bit after I purchased it in 1987, going to British Columbia, Canada. I got 6 mpg consistently, which I thought it was all it would get, but the previous owner told me he got 10 mpg on long trips. After several trips I did something I should have done after purchase--I pulled the plugs and saw that they were close to being gas fouled. The 2-bbl carb was spilling fuel into the air stream while running. After corrected, I was getting close to 10 mpg @ 60-65 mph.

My rig weighs 23000 pounds, which is a lot of mass to climb hills. The trans has a bad gap in the 3-4 shift, which becomes quite annoying when climbing long grades, which are numerous here in the West. I learned to simply be patient and stay in the lower gear at a slower speed.

I have plans to return this to the road after replacing the wheels and tires to eliminate the old rag 20" tires on split rims. I also have a new, old stock (2001) Holley pro-jection throttle body retrofit EFI system which I intend to install. It is 2-bbl sized which should ease the adaptation to the pre-magnum 2-bbl intake manifold.

Though slow on grades, the coach performs very well on the flats, and steers and rides quite comfortably. I recently had the opportunity to acquire a low-mileage 478-M with the idea I could swap it into the Bluebird, but I think I am going to stay with the workhorse 401.
Regards, Andy Carlson, Ojai CA