Thread: Turbo question for the 4BD1 experts

1. no but that depends on your plumbing
2. yes it is depending on how nuts you got
3. no idea. but Ive seen air to coolant intercoolers on them before just not sure of breed.

1. As Dave said it depends on your set up. The bonnet frame is normally the problem. I have a cross over pipe that sits flat to avoid the bonnet frame. However, in my case the turbo compressor was too big so I had to rotate it to face down. In the end the intake pipe went around the back of the motor under the air cleaner. I could have used the cross over pipe if I had used a T25 with a smaller compressor housing.

2. There are significant differences between the turbo and na motor. However, turboing a na makes a big improvement to a na motor. At 100km/h according to the before & after dyno my set up achieved over 50% increase in hp and torque.

3. dont know about this.

Originally Posted by County3.9

1. Does the bonnet need to be modified to clear the turbo-inlet manifold pipe?
2. I know this one will re-ignite some opinions...Have we decided if it's a good idea to turbo a NA isuzu yet?
3. Has anyone managed to fit a denco(sp?) liquid to air intercooler into the 110 engine bay. Looks like a compact unit.

I know KLR have done a few turbo conversions to the 4BD1. Has anyone got photos of their work?

1: yes the bonnet has to be modified for the cross over pipe.

2: yes it doesnt matter it will easily handle it.

3: KLR hasnt but you could.

KLR is the best place go there and get everything you need done!!!

Just further to Q2....at how many Km's wouldn't you turbo a NA...that is given regular servicing and a good condition base...mine has 420k...not thinking about a turbo...but hand to know.

paul

A good 4BD1 can easily do 500k - 1 mil km in a truck. As long as the engine isn't using oil, doesn't have excessive blowby, and seems to be in good general condition, I wouldn't have any problems with turbocharging, however many km it had done.

My 4BD1 was turboed at about 460K. It has now done 500K and is in the same condition as pre turbo days. I have early on pushed heaps of fuel and Hi gas temps through it to try it out, then I woke up to myself and after trashing 3 auto boxes and wearing out 1 LT95 transfer case, calmed down a little. I have no reservations turboing a NA version of this engine, just be sure you have a good example, IE serviced regularly, before you begin. I expect my engine and trans will outlast the 1992 RR body shell.

I'm using an front mounted Air to air I/C, but a water to air one is far more efficient.(up to 4 times the heat transfer)

enjoy, I am constantly enjoying driving mine...

JC

if you want o do it properly get the fuel pump rebuilt to turbo spec!!!

then you know you are getting correct fuelling instead of guessing by manually tuening your fuel screw

1: Yes the bonnet has to be modified for the cross over pipe, but if you decide to fit an intercooler in front of the radiator you can do away with the cross over pipe alltogether.


2: Yes, it doesnt matter, it will easily handle it. Even the N/A 4BD1 was designed to lugg around tons of stuff in a truck all day, every day.