> Of all the bits to change........
I was waiting for that... <smile> Overall I like the idea of the original
engine/transmission configuration, my feeling is that the engineers who
designed this put it together that way for a reason and used the best
combination of reliable parts and engineering that was available back in the
day. But, since the motor has been sitting for over 40 years its bound to
need some work and that will mean downtime for the truck - that and the fact
that highway driving (3 hours or more at a streach on CA 65 mp/h freeways)
will be plentiful concerns me for the safe running of a 270 engine in good
shape.
>The 6 x 6 drivetrain is rather lean for the existing horsepower. My
>experience (watching DUKWs mostly) is that either the intermediate diff
>goes or the intermediate output from the transfer case - one takes out the
>other not figured out which. As a completely separate problem the pillow
>block which takes the rear drive over the intermediate axle goes west if
>it isn't maintained and leaves you seized by the side of the road.
This is my big concern, overdriving the drivetrain with more HP than it was
designed for.
>The only bits of the system which never cause trouble are the gearbox
>(unkillable if unfortunate in the ratios) and the engine. My advice would
>be to stick to the stock engine and drivetrain, with particular attention
>to careful maintenance of the transfer case and pillow block. One good
>point is having a matched set of rear tyres which seems to help a lot.
Ok, maybe I need to approach this from a different direction. If one needs
to drive the 353 at freeway speeds on a regular basis what would you
suggest? It seems like the transmission drive ratios are the keeper of
reduced speeds. The primary motivator for the swap is the engine, getting
it out and taking the time to rebuild it nicely while getting the truck on
the road quickly, and not burning it up while running on the freeway. I
love the idea of keeping the transmission in there (i must be one of the
sick one who smiles at the idea of double clutching and I agree, the thing
was bullet-proof), is there a list of motors that bolt directly up, or a
source of adapter plates?
>If you must upgrade go for a newer version of the same engine. I think
>Jack Tomlins DUKW had the 302 which had more grunt in basically the same
>engine, and if you need to upgrade the engine figure on at least using a
>transfer case and drive system from a newer 6 x 6.
urrrghh, hoping to keep it simple by just swaping engine and trans and
having a new driveline manufactured between trans and xfer case. what kind
of xfer case would you suggest/recommend? Have any mpg comparisions between
the older 270 and the 302 been submitted?
> You can fit larger
>diameter tyres for more road speed if you need it - several suppliers have
>11:00 x 18 singles which have more plies in the construction and a bigger
>rolling radius.
good point, need to dig out the tire to speed calculator...
>Maybe I'm being a bit gloomy - properly serviced and used the 6 x 6 will
>go anywhere anytime, just remember transfer cases can be noisy, and can
>scream all day but still work properly....
No, not at all - I can easily respect the purist view. The truck is going
back into service vs. being restored so my mindset is not finely tuned to
keeping it all original. I appreciate your thoughts.
Mike
This archive was generated by hypermail 2b29 : Sun Jul 02 2000 - 23:51:31 PDT