Fuso Performance Chip.2

[olsurfer]

My mistake, I was calling the butterfly a jake brake.
I'll try and call a dealership to see if there is a larger turbo/butterfly unit that will fit.

 

[westyss]

On the FG the fuel tanks have a metal rectangle bit that sits inside the fuel tank bracket to prevent the rotation from occurring, maybe the FE did not come with that or as in my case I slid the tank aft a bit and the brackets no longer sit in same spot, although my tank has never rotated at all. The metal strap does have a rubber side strip that sits on the tank to provide friction.
This is the second time I have heard of the vac brake falling apart, odd, note to self- check the bolts on that!

The FM260 series also has a 'butterfly' exhaust brake. It is very well-mannered in its operation - al least on my rig.

However, I almost lost it completely one morning last summer in the Yukon. I had been off pavement and on rough roads for several days, and as I pulled onto the pavement one morning I suddenly was serenaded by a very loud exhaust noise. After pulling over I found the entire exhaust brake hanging by the air line completely out from between the two sections of exhaust pipe. Fortunately a couple of bolts I had on board got me to Whitehorse, where I could source some more. Seemingly no harm done, as I am nearly 20,000 miles later with no discernible ill effects.

Another wholly unanticipated result of rough road travel was to find that my cylindrical fuel tanks were rotating. The filler cap on the outside of both tanks was rotating up toward the underside of the house — making it increasingly difficult and then impossible to fit a fill nozzle into the hole when stopped at a gas station. I had to loosen the bands and rotate them back down before tightening them up really well. [I was shown how to do this by a local contractor who told me that it happens all the time to cylindrical-shaped tanks when operating on rough roads. After I got home, I slipped some rubber strips between the bands and the tanks before retightening. They don't seem to rotate at all now. I also put small strips of marker tape on the tanks and bands so I can detect any rotation early on.

Just two more unanticipated things to check on regularly — after I learned about them. Getting to be a pretty long list.

 

[westyss]

My mistake, I was calling the butterfly a jake brake.
I'll try and call a dealership to see if there is a larger turbo/butterfly unit that will fit.

That has been done already, to be able to go to a three inch exhaust a change in the vac brake is needed and this seems to be a popular thing to do, maybe some updated info on a bigger exhaust can come from this thread and how it was done and if a noticeable change in power as a result. Skifreak does have some info for that here; http://canter4x4.com/technical/an-isuzu-exhaust-brake-on-a-fuso/#more-323
That might not be cost effective though but it looks like any additional power is going to come at a cost!

 

[SkiFreak]

Yep... as Westyss has mentioned, I replaced my OEM 2 1/4" exhaust with a 3" one, which included replacing the exhaust brake.
The butterfly assembly I used came from an Isuzu and, much to my surprise, it was virtually identical in design to the Fuso one, making the conversion very simple.
The only other thing I needed to do was to manufacture some mounting flanges to suit the new butterfly assembly. I had these cut to shape (laser cut) then I machined the 45 degree seats. All in all this was not a difficult modification.
I cannot tell you if there was an actual power increase after installing the 3" exhaust, as I did not do a before and after dyno test. At the time, power was not my motivation for replacing the exhaust; routing it where I wanted it to go was.
I will be adding a chip to the truck in the near future and when I do that I will probably put it on the dyno then.
The stated output for a standard FG84D is meant to be 110kW, so if I am getting more than that "pre chip" then obviously the exhaust will have made a difference.