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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: jaypullen on July 02, 2010, 09:12:33 AM

Poll
Question: more power 6v71
Option 1: 6v71 votes: 1
Option 2: 6v71 votes: 2
Title: 6v71 power
Post by: jaypullen on July 02, 2010, 09:12:33 AM
Does anyone know how to get more power outta my 6v71 hills kill me Blower but no turbo I removed all the ac and seats When i have the bus is loaded I have maybe 3000 pounds of  cargo. Its a 40 passinger bus = 4000 to 4500 of  cargo abound when it was a coach I think in way under the 40 passinger rating any help Thanks JPULLEN
Title: Re: 6v71 power
Post by: Lin on July 02, 2010, 09:14:42 AM
What injectors do you have?
Title: Re: 6v71 power
Post by: luvrbus on July 02, 2010, 09:26:33 AM
you are not going to get much more than 238 hp from that engine anything above that you are asking  for trouble
Title: Re: 6v71 power
Post by: jjrbus on July 02, 2010, 10:47:07 AM
The best change you can make with a 6V-71 is yourself. Learn to sit back, relax and enjoy the trip. Once you stop trying to push the pedal through the floor your leg will hurt a lot less ;D  BTDT
                                 JIm
Title: Re: 6v71 power
Post by: Just Dallas on July 02, 2010, 11:15:02 AM
Removed
Title: Re: 6v71 power
Post by: jaypullen on July 05, 2010, 07:42:41 PM
Its a 1977 40foot 2 axel  mci 6v71 with 299k (never rolled) allison auto Ive ran this bus up a stretch of highway near livermoore at 50 mph in 3rd but over the last couple weeks I cant get 25 to 30 out of it in 1st or 2nd  It has black smoke coming outta the exsaust all the time real bad under load I mean 10 feet of black smoke behind me Any ideas Thanks JPULLEN
Title: Re: 6v71 power
Post by: buswarrior on July 05, 2010, 07:52:24 PM
Lots of smoke? All of a sudden, mileage wise?

Has an animal built a nest in your air intake?

Something has changed A LOT for that kind of performance change and all the black smoke.

Check all of the intake piping for obstruction, and what is the condition of your air filter?

Basic maintenance before worrying about what motor you have.

happy coaching!
buswarrior
Title: Re: 6v71 power
Post by: TomC on July 05, 2010, 09:23:01 PM
If you're getting black smoke and no power-you're not getting enough air to the engine.  Pull the entire air inlet system until you find either the obstruction, or terribly dirty air cleaner.

As to getting more power, with N65 injectors, you will get 228hp and 600lb/ft torque (that's real horsepower, not the 238hp advertised).  To up the power, you would have to rebuild it to a turbo engine with turbocharger and air to air intercooler.  With 80 injectors, you could get 300hp and 900lb/ft torque.  If it were me, I'd simply pull the 6V-71N and replace it with a 6V-92TA since the two blocks are identical with outside dimensions.  Then you could have 375hp and 1125lb/ft torque with 100 injectors (nearly twice the torque of your 6V-71!).  Good Luck, TomC
Title: Re: 6v71 power
Post by: RJ on July 06, 2010, 01:16:31 AM
Jay -

Something's quirky here:

Quote from: jaypullen on July 05, 2010, 07:42:41 PM
Its a 1977 40foot 2 axle  mci 6v71. . .

Is this an MC-8 Highway (Greyhound) coach, or a transit bus?  Weird to have a two-axle charter coach of that vintage from MCI w/ only two axles.

Is it a "T-drive" or a sideways-sitting "V-drive" powertrain?

Perhaps a picture would help us help you better?


Quote from: jaypullen on July 05, 2010, 07:42:41 PM
I've ran this bus up a stretch of highway near Livermore. . .

You mean as in Livermore, Pleasanton, Dublin, etc?

FWIW & HTH. . .

;)