BCM Community

Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: TradeCities on April 20, 2009, 08:59:16 AM

Title: 6-v71 RPM's
Post by: TradeCities on April 20, 2009, 08:59:16 AM
Does anyone know the factory rpm's of the 6v71? I know I need a tack I am just wondering.
Title: Re: 6-v71 RPM's
Post by: luvrbus on April 20, 2009, 09:05:40 AM
TC, depending on the application most transportation engines were 1900 to 2100 rpm   good luck
Title: Re: 6-v71 RPM's
Post by: buswarrior on April 20, 2009, 09:58:30 PM
regularly taken to 2300 rpm in short geared transits to attain some semblance of highway speed.

Which is your configuration.

happy coaching!
buswarrior
Title: Re: 6-v71 RPM's
Post by: TradeCities on April 21, 2009, 06:45:59 AM
Hey guys I appreciate your response. What is the best way to hook up a tachometer on this rig?
Title: Re: 6-v71 RPM's
Post by: buswarrior on April 21, 2009, 12:01:56 PM
a little piece of reflective tape on the pulley face and an optical tach for setting it.

Handheld gun unit, it counts the flashes as the motor spins, digital read out.

I don't know that I'd want to use an alternator driven tach to set the governor....

happy coaching!
buswarrior

Title: Don't Be Afraid To Rev Your 6V71 Detroit
Post by: HB of CJ on April 21, 2009, 06:28:46 PM
Don't be shy.  A 2100 rpm CRUISING speed ALL DAY LONG will not hurt your mighty 6V71.  And, with a little work and some marking pens, you will find you don't need a tack either.  Easy to rig a cheap substitute.

The problem will be researching the tranny gear ratios (plus while in convertor mode if you have an automatic) of your tranny, plus figuring out what the rear end ratio is, plus your actual tire rolling diameter.

From all of that, it's easy to mark your speedo with points expressing whatever upshirt/downshift/cruising  rpm you desire.  Greatly exceeding 2100 while upshifting will not hurt your 6V71 Detroit either.

How exceeding?  Well, 2300 to 2400 intermidiantly (sp?) thru the gears won't hurt it either.  Just don't leave it there.  If your Bus Conversion is very tightly geared, your fuel mileage will suffer, but you can speed.  HB of CJ

6V71 rpm Post   (Speeeel check: what's that?)