871 turbo

[jaybe_2]

Doe's any one know what the torque rating of an 8v-71 TA is? I was told the HP was 350, doe's this sound right. It seems low considering a non torbo is 318HP.

[TomC]

There were several ratings with several injector sizes.  But in the end of production with bypass blower and aftercooled block, the 7G75 injector yielded 370hp with 1125lb/ft of torque.  The 7G80 injector yielded 400hp and 1200lb/ft torque.  The 8V-71 was more receptive to horsepower upgrades than the 8V-92.  If you use a air to air intercooler instead of the aftercooler in the block, you can go even higher.  My bus is being turbocharged by Don Fairchild in Bakersfield.  I had a custom air to air intercooler made and mounted it.  Don has just about taken the engine apart inspecting it because of a low oil pressure problem-which turned out to be an open oil supply to the gear drive for the radiator fan.  Don installed a reducer to 1/8" and brought the oil pressure back up to 60lb from the dangerously low 25lbs.  The engine was on the dyno for tuning and blew out the blower seals at about 7psi of turbo boost.  Eventently the blower had not been rebuilt recently, since all blower seals now are turbo compliant.  I anticipate the engine to be 370hp with 1125lb/ft since we used 7G75's.  Hopefully by the end of next week, we'll know what it dynos at (hook up the engine to the dyno while on the engine cradle without the transmission).  Looking forward to more oomph and hopefully better fuel mileage.  For now, am not changing the rear end.  Good Luck, TomC

[jaybe_2]

I am going from a non turbo 871 to a turbo 871, my bus has a 5 speed allison do I need to worry about the extra torque from the engine? Also what about radiator size to take care of any extra heat?

[RJ]

I am going from a non turbo 871 to a turbo 871, my bus has a 5 speed allison do I need to worry about the extra torque from the engine? Also what about radiator size to take care of any extra heat?

If you've got an HT-750 or 754, it will easily handle the output of an 8V71T.

As for cooling, you don't mention which coach you have.  Some can handle it "as is", others require additional attention.

FWIW & HTH. . .

[jaybe_2]

Sorry my bad. It is an '85 prevost xl.

[RJ]

Call Prevost Parts and see if they used a different radiator in the '85's that came with an 8V71T, as it was an option back then.  While you've got them on the line, ask about the 8V92TA's radiator, as it, too, was an option.

FWIW & HTH. . .