4BD2T J60 TI Another Isuzu Conversion (2 Viewers)

[FL cruiser]

Brake booster is a GM Hydroboost.
Not sure how a stock brake booster would clear the turbo because I was using the Hydroboost before with the old engine.
The Isuzu does come with a vacuum pump built in the back of the alternator.
There are some very small 7" dia aftermarket brake boosters available that are cheap and work well.

 

[RHINO]

very nice, congrats on getting it done. it sounds like the mounts will work out well and maybe i'll switch mine over. for comparison sake in typed word i can tell you my mirrors dont vibrate and the steering wheel is smooth at all rpm.

 

[TURNMEOVER]

this thing is a tourque monster. I have wheeled and with and rode 600 miles in this rig and all i can say is wow. what a cool rig. I would trade my 40 in a heart beat for it.

 

[warpdriv]

Now that you have had this awhile, how do you like it and what would you do different?

 

[FL cruiser]

Not really much I'd do different. Still very much like it, and would do it all over again.

I might have opted for an NV4500 over the H55. The only reason is that is the teeth of the H55's input gear came off once about 2,000 miles from home. I have since found out that it's a common scenario of having too small of a tranny behind a long stroke 4 cyl diesel. The torsional vibrations are rough on a small tranny. The H55 in no way that small a tranny, and i hope what happened is just a one time deal.

Love the combo. Drove out to west to Moab and back last summer, 5,000 miles round trip. Got great mileage, averaged 19MPG. There's enough power to cruise up mountains passes w/o having to do lots of downshifting. Engine is smoother and quieter than I expected. I wouldn't hesitate to use an Isuzu again.

 

[Adam R]

I have a 4bd1t sitting in the garage with plans of it going into my 80 series. I'm leaning toward the 4l80E tranny, but I'm curious how much boost you are running and what were your EGT's pulling the passes in Colorado. Do you remember what speed you pulled the passes at?

My end goal is being able to run up 40 lbs of boost so there is some work that needs to be done to the engine before it actually goes into the vehicle.

Nice build up and I'm glad the Isuzu is working out for you.

Adam

Thanks,

Adam

 

[FL cruiser]

Currently running 15lbs of boost, EGTs top out at 1,400 deg F going up a steep grade.
I do remember having to drop down to 3rd gear/40MPH in a few places, but went up many grades in 4th gear. It couldn't quite keep up with a friends stock FZJ80 we were following, but I feel it would would be twice a s fast as my HJ60 or 6.2 60 in similar situations. It's not that quick, but still impressive considering it's only a 3.9.

Adam, Would you plan on manual shifting or getting a stand-a-lone for your 4L80E ?

I once wheeled with a guy that had a 4BD1T in a buggy. It would achieve over 40 PSI boost when he could get traction. Very powerful and impressive.

 

[Adam R]

6 months ago I was leaning toward putting my 2.4L 2L diesel in the 80 series and went ahead and installed a clutch pedal. While the 2L is little on the small side, my engine is turned up well beyond factory and it runs awesome. It will pull Vail pass at 60 mph in my 4000 lb 84 Toyota PU.

Now that I've come across a running 4BD1T, the 2L will stay in the PU and the 3.9 will go in the 80 series. I've come to really enjoy wheeling with an auto tranny in the 80 so I'm leaning toward staying auto and using a standalone computer for the tranny. The down side is the $5000 it will take to make it happen. (Engine rebuild $1000, 2 separate adapters $2000, 4l80E tranny $1000, stand alone computer $500, etc $500) I'm shooting for 250 hp and 500 lbs of torque from the 3.9 at full song. From what I've seen of the engine so far, this shouldn't be a problem.

Oh, yea, I'm already mocking up the twin turbo setup.

Adam

 

[Nexxussian]

Adam, which turbos are you using?

Don't forget the head studs.

 

[Adam R]

Agree.

My donor 3.9 ate part of the turbo and compression is down on one cylinder. I'm going to pull the head and have it gone through. Since I plan on keeping this engine for a long time, I'll have the head fire ringed and re-build the rest of the engine while it's apart. The guys on the 4bd forum have already figured out which ARP studs are required for this engine so it will be put together to handle the boost. I picked up a nearly new HX35W the other day and I'm debating which smaller turbo to go with it. I may just run the 35 alone to see how it does, but from what I'm told, it will max out around 30-35 lbs of boost by itself. Compared to the stock T25, that HX35 is absolutely huge.

Carcrafter on that site is running around 80 lbs of boost through his twin setup. I don't need that much HP, but 40 lbs should work just fine. If I can pull Vail pass at 70 mph, I'll call it good. Everyone said there was no way I could run 20 lbs of boost through my 2L. After 10 years with a lot of hard towing, it's still running just fine and getting almost 30 mpg on the highway.

Fortunately my 80 series runs perfectly fine, (aside from the dismal fuel mileage) so I'm in no hurry to get busy on the engine swap. I need to wrap up a few other projects first.

Adam

 

[Adam R]

This was one well worn turbo. Engine did run, but guy said it wouldn't get above 35 mph. Turbo was actually seized, but for $300, I figured it was worth the gamble.


Adam

 

[Dougal]

6 months ago I was leaning toward putting my 2.4L 2L diesel in the 80 series and went ahead and installed a clutch pedal. While the 2L is little on the small side, my engine is turned up well beyond factory and it runs awesome. It will pull Vail pass at 60 mph in my 4000 lb 84 Toyota PU.

Now that I've come across a running 4BD1T, the 2L will stay in the PU and the 3.9 will go in the 80 series. I've come to really enjoy wheeling with an auto tranny in the 80 so I'm leaning toward staying auto and using a standalone computer for the tranny. The down side is the $5000 it will take to make it happen. (Engine rebuild $1000, 2 separate adapters $2000, 4l80E tranny $1000, stand alone computer $500, etc $500) I'm shooting for 250 hp and 500 lbs of torque from the 3.9 at full song. From what I've seen of the engine so far, this shouldn't be a problem.

Oh, yea, I'm already mocking up the twin turbo setup.

Adam

Sounds like a good fun mix.
Some considerations for your build though.

First is your power and torque goals are beyond the standard pump even maxed out. You'll need to find some plungers bigger than 10mm or with more lift. Randy can help here.
The stock pump is good for about 200hp depending on your plunger sizes. Most US engines seem to have 9.5mm plungers, I have 10mm plungers in my JDM engine.

You'll need just above 30psi and a very good intercooler when you can get that much fuel. The holsets can run this pressure range fine, but I don't know how short the rev range under boost will be. Compound is definitely the best way but I'd run it as a single first and see how it goes.

I think you'll need to add some extra weight to the flywheel to get it running smooth enough to be usable at that torque output. The stock flywheel is quite light and things get rough with double the stock torque at low rpm. I'd double the weight of the stock flywheel if possible. This puts it on par with the 4BT flywheel weights.

You think the 4L80 is up to it? I'd prefer more gears myself. I run the Isuzu 5 speed manual.

 

[Nexxussian]

While I agree with Dougal about more fuel, the twin setup should help you achieve your goal, with a broader torque curve.

While the ridiculous boost Randy achieved when the trans mis shifted with the twins isn't needed the HE341 and HX52 seemed to work well together.

If you want the broader torque curve, with earlier boost onset, as well as less total power potential (something less than hero levels ) I've seen reports of a HX30W over a HX40.

The '30 should spool in the first 20 feet or so, with the '40 following shortly thereafter.

For that to work the '30 either needs the wastegate ported out, or an external wastegate as the turbine chokes out and the passage through the turbine housing seems to be small enough (stock) that the '40 doesn't want to light, and the engine seems to choke out much over 2800.

All of that is from memory, and compiled from several sources on 'BT swaps.

I've got a '30, as well as the HY35W I'm running on the NPR. I also have an old T50 that needs some work.

I've been debating which to pair togehter, when I pull the T50 apart I'll measure the wheels to see which it's closer to (HX40 or HX50-55).

Food for thought, hope it helps.

 

[Nexxussian]

FL, sorry about the hijack.

 

[Adam R]

Yes, sorry about the Hijack as well.

All good points and the pump and injectors will modded slightly as well. 40 psi is the max and I may never actually need that much. In looking over the flow charts, I might be able to get away with using an existing T3 I have with an external wastegate, much the same way guys are using the twin turbo set-up on the Ford 6.4's. The small turbo needs additional bleed off when you turn them up to keep back pressures within check.

Stock the Isuzu is rated at 126 hp. Doubling that shouldn't be an issue, especially when you add an intercooler, more boost and more fuel. Like my 2L, which has evolved over 15 years, increases will come incrementally. The reality is that very few people are pushing the envelope on these engines with Carcrafter being the exception. Many of 4BT guys are pushing well beyond 250 hp. For additional flywheel weight, when you run the IDS kit, you have an stock flywheel, adapter, and torque converter spinning. Hopefully that will be sufficient weight.

Adam