A little background. I found a 1978 QuadraVan (4x4) on a E250 that is in great shape. My plans are to make a true off road vehicle out of it.
I am going to get bumpers made, receiver mounts for a warn winch that can be removed and used front and rear, full length rack on top, and a few off road lights. I have already removed the running boards and replaced them with super hoops. A great looking addition to the van.

The only problem I have with it is the 460/C6 combo. I have been thinking of replacing the low mile 460 (80k) with a crate 351 with an AOD tranny. I plan on keeping my NP205 transfer case.

But, I am not real sure I would save that much in gas to justify the swap. I change jobs every 3 months, and often drive 1k miles home and then back to new job. I then use the van for primary transportation while at new job.

So, I guess the question is: Is it feasable to do a swap from the 460to a more fuel efficient FI engine/tranny combo without spending the amount of a new van on the process?

Open to any and all suggestions.

thanks
bob

 

A carbed 351 will get 10-12 all over, the carbed 460 will be about the same maybe 8-10, and if you are using it hard (muddin) you'll only get ~4 out of either so I'd take the 460, and the c6 is a whole lot more bullet proof than an AOD.

 

Exactly the kind of info I was looking for. Thanks for the input.

bob

 

You could buy a lot of fuel for what it would cost for the conversion, not to mention the headaches. You would probably get around 25% better gas mileage with 50% less torque.

Here is some math:

For every 10,000 miles driven

13 mpg = 769 gal of gas
10 mpg = 1000 gal of gas

diff= 231 gal of gas x 1.75= $404.

 

I have had a carbed (2bbl) 351w/c6 in a 1982 E350 ext Club Wagon, it got 12mpg at best. The 460 will do about the same. He already has the 460 and will not see much if any difference in fuel economy.

 

Ok, you guys covinced me. It didn't take much. Now all I have to do is find someone who makes headers for this van/engine combo. Then replace the intake and carb, or just have the carb that is working rebuilt. That should take care of my needs for this van, engine wise. Who knows, maybe do an electric overdrive down the road a bit.

bob

 

Get an edelbrock intake, (autozone can order them) and a nice edel carb. They come from the factory tuned pretty well, and are very easy to work on.

 

The Edelbrock is the way to go I put a preformer intake w/ cam and timing set and carb w/elec choke 650 cfm.Runs great . I like to see a Pic of this van If you have any.And good luck with the headers the set that was to fit my 76 E150 where to big ,hit the cross member.