8v71 power

[Ericbsc]

I have heard my 8-71 called the dragonfly several times. Fly down one hill, and drag up the next. I know this does not help but thought it very true!!

[MCI-RICK]

Jack,

My MCI has the V Drive.  It looks like a transit bus but only has a front door. No rear door. Oh, and can it do about 72mph. The paper work calls it a "Suburban Cruiser" also know as the "Classic".   No real storage space to speak of and so I've been shopping for another bus. May be picking up a 1970 GMC PD4905 with the 8V71 and V730D tranny.

Rick

[brando4905]

Rick,

This is what I get for ASSuming!   If your MCI is a V-drive, then it probably will go right in the 4905.

[MCI-RICK]

brando,

No problem here .  I want to explore all possibilities before I jump in.  Don't want to explain to the boss (wife) why I need a third bus lol

Rick

[JackConrad]

Jack,
My MCI has the V Drive.  It looks like a transit bus but only has a front door. No rear door. Oh, and can it do about 72mph. The paper work calls it a "Suburban Cruiser" also know as the "Classic".   No real storage space to speak of and so I've been shopping for another bus. May be picking up a 1970 GMC PD4905 with the 8V71 and V730D tranny.
Rick

OK, I learned something new today.  Thanks for the information.  Jack

[TomC]

After turbocharging my 8V-71 with air to air intercooler, now pulling a hill at any altitude, usually clear exhaust and no power reduction.  When over 8,000ft, will get a bit of smoke, but hardly worth mentioning.  The 71 series is much stronger then the 92 series.  71 series is less prone to head cracking, won't leak because of dry cylinder linings, and with 80 injectors will put out 400hp and 1200lb/ft torque-more then a 6V-92TA will be able to stay together putting out.  Good Luck, TomC

[Barn Owl]

These are not right or wrong answers, but good, better, best situations. It all boils down to money, the more of it you have the better you can have. If you have the funds, build the 8v71 turbo like TomC did, if not go the other way. Regardless of how much more durable the 8v71 is, we are putting our engines in bus conversions, and they see far fewer miles compared to what they were designed for. If the 92 series holds up well enough in transit service then it would hold up more than just fine for my application. BTW, for V drive owners I don't think 400hp would be a good thing.

[RJ]

Rick -

The powertrain out of your MCI muzzle-loader will work fine in a 4905.

The difference will be 102" vs 96" width, so you'll have to swap cradles.  Some other adjustments will also have to be made, like radiator fan shroud spacing, etc.

I'd use the MCI radiator if it's bigger (thicker) than the one in the '05 and you can shoehorn it in.

Is the MCI's 6V a DDEC?  If so, you'll need all the associated wiring for it and the ATEC transmission.

If it's not a DDEC/ATEC combo, then you can easily "hot rod" the 6V to 350 hp, which will be sweet in the 4905.

Would it be worth it?  Tough call.  Do you know the history on both powertrains?  Based on history, you can make the call, as it's a relatively easy swap, compared to some of the others busnuts have done.

FWIW & HTH. . .