Posted by Paul (in NY) on Sunday, December 24, 2006 at 19:18:40 :
In Reply to: 4bt - 4bta question. Vaccuuum Paul ?? posted by wet coast bruce on Sunday, December 24, 2006 at 18:19:41 :
You need to acquire and install either CAC (charge air cooler) aftercooler or a Liquid/Air Aftercooler. The liquid/air are used on CPL 857 engines. The CAC requires the charge air cooler to be placed in front of the radiator and 3.0" pipe for turbo air to and from the CAC. You will also need to index the Bosch VE pump to a new timing position as indiacated on the drive gear. Then you need to have the Bosch VE pump re calibrated by an injection pump shop to the configuration you changed to.
My Carryall and M37 have Liquid/Air Aftercoolers (cpl 857) Typically a CAC aftercooled engine is a CPL 1260 or CPL 767.
I am going to convert the CAC aftercooled engines I have to Liquid/Air for use on the Bumblebee and DevilBear. If you look at the construction in the front (radiator area) on a PW/WC , it would take almost magic to route 3.0" pipe to/from the CAC. On a M37 its a snap to route 3.0" pipe due to different construction. Look under your hood and visualize routing 3.0" pipe to the front of the radiator.
With this all said, I WOULD NOT pass by on a Nice 4BT. Typically ( depending on CPL) a 4BT is 105 hp. The CAC aftercooled, CPL 1260 and 767's are also 105 hp. The CPL 857 is 120 hp. I honestly dont think you will ever see a real difference in 105 or 120 hp in driving our old iron.
When you get your 4B series, be sure to resolve the KDP (Killer Dowl Pin) Issue while its out in the open. It would be most difficult to resolve when installed in the truck, but can be done.
Paul
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