Pac Brake on a 6.5

[Stratosurfer]

All,
Just picked up a 90 model Diesel Pusher motorhome w/Pac Brake. This is the 8.3L cummins and the PacBrake is a sweet addition. Anyone put a Pac Brake or other engine brake on a 6.5? I would have to think this would save on brake religns and help terrifically in hilly areas such as where I live.
Thanks

[Robyn]

The regular exhaust type brake (Jake** Jacobs***) is a wonderful device and the best addtion to Heavy trucking since the advent of sliced bread. :D

The exhaust "flap" type brakes are a big help on the smaller engines like the cummins 5.9 and the T444E IH (Power stroke)

I have not seen any exhaust brakes applied to a 6.5.

Try doing some google searches and see what shakes out of the trees.

Best

Robyn

[Robyn]

I did a little search and found that BD makes a turbo mounted brake for the 6.5

This device is "similar" to the Pac Brake in that it is a flap type back pressure retarder.

Too bad a real Jake type brake cant be purchased for these small engines.

The Jake works on an entirely different principal as it uses engine compression to retard. The compression is released via the mechanism by opening the exhaust valves just before the injection would take place.

This is accomplished by using a hydraulic mechanical unit that transfers the motion of adjacent valves via oil pressure in the unit to "pop" open the exhaust valve just at or slightly before TDC.
The function is to allow the engine to use power to compress the air in the cylinder and then dump that air and then the engine drags the piston down on a "dead" hole.

In effect the engine becomes a power absorbing air pump.

The Jake units bolt onto the valve train over the valve rockers.
To do this on a 6.5 or other small automotive diesel engine would require some serious redesigning of things up top.

The valve train on these engines is probably not strong enough to stand the stress.

Hope this tid bit on the BD brake helps

Robyn

[Hubert]

Read on another forum that the GM Autos OBD-II of the 6.5 era won't compression brake without some mods??? The Allison's will but not the 480LE?'s I believe.

The manuals could use it and I think the OBD-I's have realitively easy torque converter lockup add ons.