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Discussion Starter · #1 ·
My test truck is a 1992 Landcruiser FJ80. The truck has 2”-3” suspension lift with a 2” body lift and is currently sitting on 35’s. Custom bumpers, rock sliders, etc. and weighs about 6500 pounds. Basically it’s a brick with a fat ass. I installed the Isuzu 4BD1T and started to play with this DD project.
I live in a hilly area, and that plays a factor into my testing. The ‘test hill’ is about 8% grade for 1.5 km. Not that steep, not that long, but it’s a good test for fat assed FJ80.

Stock Turbo was a little IHI unit. The truck made slightly more power than the stock gas engine, but not much. Around town it moved the truck around just fine, but don’t try to win any races. On the test hill the stock engine would produce 12-13 psi and the egt’s would be at 1300⁰F. I’d take a run at the hill in overdrive and need to pull down into drive about 2/3 the way up the hill. “I put my foot on the floor and let the diesel do the work” (Kazzer – Pedal to the metal). I knew the Isuzu could do better – it had too.

The next turbo was a HE221W. I rebuilt the engine and installed a Stage 2 cam and lifters from Colt Cams in Vancouver, Canada. Had the injectors worked on for more flow (I don’t know what was done). I cranked up the injector pump to see if all my hard work was going to pay off.

With the fuel screw removed, the HE221W made AWESOME power around town. I could make those 35’s talk. Only a small cloud of black smoke as I stabbed the throttle and the truck lunged away from those import tuners. The HE221W would run about 10-12 psi driving down the highway and make 29 psi boost going up the test hill. It was way too much fuel for the test hill, so I had to lift the throttle to keep the egts below 1300. By the time I got the top of the test hill, I was going only slightly faster than the stock turbo with twice the boost pressure.

The turbo spools fast and makes good boost, but it seemed to be chocking under load on the highway -it’s got no legs! I turned down the fuel to make it over the test hill and not exceed 1300⁰F. Now the truck hardly smoked at all and most of my tire twisting torque around town was gone. I’d still take a run at the test hill in overdrive and need to pull down into drive about 3/4 the way up the hill. Much better than stock, but I need more!

My new turbo was a Borg Warner S252 SX-E. I cobbled together a stainless turbo manifold out of some schedule 40 elbows because I thought the stock exhaust manifold might not do the new turbo justice. The BW is quite a different animal, compared to the HE221.

I turned up the fuel only a little bit more than my conservative setting for the HE221W. The truck now runs down the highway with only 3 -6 psi, so much less boost then previous turbo. Without a run at the test hill and in overdrive gear, the turbo pushed up to about 19 psi boost with 1300⁰F egt, and just went over the hill without hardly slowing down. The truck maintained speed very well and my foot was not quite on the floor, but close.

The new BW turbo runs a lot cooler. After driving around for a couple hours I can pop the hood and still touch the compressor housing. It’s hot, but nothing like the HE221W was. I was surprised with ‘more legs’ at less boost. The BW is slower to spool up, even with a .63 A/R on the turbine, but that was expected. I’m rolling a bit of coal, but overall I’d call it a successful turbo upgrade.
 

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Are you intercooled?

The IHI is good for over 20psi if you cranked up the wastegate arm. The HE221 is a turbo that can do higher boost but it isn't efficient. Below 30psi a TD04HL-19T (closely related) is a lot more efficient and produces cooler boost.

The BW has a bigger compressor and turbine. It's going to produce top end power better than the others but give it away down low. It will really suffer at low rpm and altitude and struggle to run clean.

In terms of turbine size:
IHI RHB6 is 11.8lb/min choke flow.
HE221 (6cm) is 13.3 lb/min choke flow.
This S252SX-E is 20.9 lb/min choke flow.

In terms of compressor size:
IHI RHB6 max flow is ~29lb/min
HE221 max flow is ~36 lb/min
S252SX-E is ~53 lb/min.

A 4BD1T producing ~200kw at 3000rpm needs ~34 lb/min at a PR of 3.

To move a 3 ton landcruiser up an 8% grade at 65mph takes 100kw at the wheels (~135hp). Your rpm is enough to calculate the torque on that.
 

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Discussion Starter · #3 ·
I have a small intercooler connected the the turbo - literally. The intercooler sits on top of the engine and gets air via hood scope. I couldn't find room up in the grill area, so I copied a Subaru idea and mounted the intercooler on top of the engine. Not the most efficient cooling, but it's simple and saves on piping.

My truck is my daily driver/toy. I put on about 1000 km/week with mostly highway driving. The HE221 is nice in town, but wasn't getting it done on the highway. It ran fine and all that, but I've got a bit of a heavy foot and like to get where I'm going. The HE221 provided good clean transportation, but lacked any fun on the highway. I had to 'plan' to pass people and it wasn't a consideration if there was any kind of hill involved.

When my HE221 started to leak oil into the compressor, I knew it was time for an upgrade. My historic research on this site and others, said the HE221 was 'THE' turbo to get, but it left me wanting more. I read all the comments, opinions and maps. I played with MatchBot and knew the BW was a little on the big side, but after my HE221 experience I decided to take a chance.

I know an engine is just an air pump with a certain volume of air in/out at whatever rpm - the math doesn't lie. And as you point out the HE221, on paper, is the perfectly matched turbo for the 4BD1T, but my ass in the seat says something different. I figured my engine upgrades would help a bit with efficiency, and the .64 A/R on the BW would help spool a big turbo quicker. I was shocked in how the truck went up and over the test hill - lower boost = more power. Maybe it's not all about the math?
 

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I have a small intercooler connected the the turbo - literally. The intercooler sits on top of the engine and gets air via hood scope. I couldn't find room up in the grill area, so I copied a Subaru idea and mounted the intercooler on top of the engine. Not the most efficient cooling, but it's simple and saves on piping.

My truck is my daily driver/toy. I put on about 1000 km/week with mostly highway driving. The HE221 is nice in town, but wasn't getting it done on the highway. It ran fine and all that, but I've got a bit of a heavy foot and like to get where I'm going. The HE221 provided good clean transportation, but lacked any fun on the highway. I had to 'plan' to pass people and it wasn't a consideration if there was any kind of hill involved.

When my HE221 started to leak oil into the compressor, I knew it was time for an upgrade. My historic research on this site and others, said the HE221 was 'THE' turbo to get, but it left me wanting more. I read all the comments, opinions and maps. I played with MatchBot and knew the BW was a little on the big side, but after my HE221 experience I decided to take a chance.

I know an engine is just an air pump with a certain volume of air in/out at whatever rpm - the math doesn't lie. And as you point out the HE221, on paper, is the perfectly matched turbo for the 4BD1T, but my ass in the seat says something different. I figured my engine upgrades would help a bit with efficiency, and the .64 A/R on the BW would help spool a big turbo quicker. I was shocked in how the truck went up and over the test hill - lower boost = more power. Maybe it's not all about the math?
What's your gearing?
 

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Discussion Starter · #5 ·
I've got stock diff ratio at 4.11; the 700R4 tranny has a .696 overdrive; sitting on 35" tires. As you can see, my overall ratio is very high.
 

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How's the 700R4 liking all that torque? It must have hated the HE221.

My calcs say about 1700rpm at 100km/h. What speed are you going up this hill?
 

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Discussion Starter · #7 ·
My 700R4 has been a journey unto itself. I've broken the rear planetary set twice and grenaded one torque convertor. I'm currently running 5-pin planetary sets and a Hugues X-HD diesel convertor. Actually that was another reason I thought the BW would be a better turbo, because I can make it out of first gear before it spools up too hard.

About 100 kph is about right for the test hill. I usually run the convertor unlocked, so rpm are slightly higher when going up the test hill. The BW pushes up the hill easy, whereas the HE221 had more boost but struggled more. The engine 'feels' a little more free and easy going up the test hill. That may be psychological, but I've work on and drove the crap out of the truck for +5 years so I've got a good idea of how it 'feels'.
 
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