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I promised this one a long time ago. I just tweaked some existing numbers to show what is possible.
Single turbo.

Calculations are done for a HE221 with 6cm housing. Other turbos below that will work:
HX30-6cm (44mm or 46mm intake versions).
HE221-6cm (7cm will do too)
TD04HL-19T doesn't have the boost capacity. Aftermarket wheels may help this.
Set the wastegate to 30psi which you should reach by a bit over 1800rpm.
Target A/F ratio is 18:1.

You'll need a large sized air/air intercooler. You need to take intake temps down from about 180C out of the turbo to about 50C into the engine. Your air filter and intake needs to handle 400CFM (30 lb/min).

Your injection pump will need to deliver ~180cc/1000 shots. All of them can do this. You can find this point by tuning in EGT or A/F or by asking a pump shop to set it at that point.

Peak boost and torque are expected around 1800rpm and peak power around 2500rpm. This gives you a decent power band for good drivability. Peak torque will be around 800Nm from a about 1700rpm to a bit over 2300rpm.

Peak crank power is expected 190kw (256hp) at 2500rpm.
 

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Sounds like an easy enough formula. Basically, a good turbo with an intercooler and adjust the injection pump for fueling. Your torque calculation sounds right. 800 nm = 590 lb ft. You didn't mention a change in injectors. 250 HP is going to be pushing the stock 4x.012 or 5x.010 units to their limits. The marine 250 HP 4bt used 5x.012 injectors. A change in governor spring isn't required to reach the HP but does help with gear changes on some transmissions.
 

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Discussion Starter · #3 ·
Sounds like an easy enough formula. Basically, a good turbo with an intercooler and adjust the injection pump for fueling. Your torque calculation sounds right. 800 nm = 590 lb ft. You didn't mention a change in injectors. 250 HP is going to be pushing the stock 4x.012 or 5x.010 units to their limits. The marine 250 HP 4bt used 5x.012 injectors. A change in governor spring isn't required to reach the HP but does help with gear changes on some transmissions.
Do we have anyone who's dyno'd a maxed out VE pump on stock injectors? I remember one user ages ago with a compound VE pump motor who got about 300hp. But I don't remember the extent of other mods.
The reason for dynoing the maxed out VE pump is they do about 180cc/1000 shots.
 

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I'd say 300 HP is kind of pushing toward the limits of a stock VE injection pump. One thing that should be known is which VE pump you have. The base 4bt road engines used Bosch part 0 460 424 055. That number tells you some valuable info. 0 tells you it's a complete unit. 460 tells you it's a distributor pump. The 4 tells you it's a VE pump. The 2 tells you the plunger diameter which is a very important number. In this case 2=12mm. Plunger size codes are as follows: 8=8mm, 9=9mm, 0=10mm, 1=11mm, 2=12mm, 3=13mm, and 4=14mm. So somewhere out there are VE pumps with 2 plunger sizes larger than was used on our stock 4bt. Heaven only knows where you'd find one. Back to the part number the next 4 tells you the number of cylinders. And the last 055 numbers tells you the application. I browsed a company list showing dozens of VE pumps and almost all were the 12mm plungers. Found no numbers for the 13mm or 14mm. I suspect those are quite rare. The other main inline injection pumps, A and P, can be built to staggering fuel levels. The A can be had up to 900cc, P3000 to 1100cc, and P7100 to 1700cc. That P7100 would about suck it as fast as the fuel nozzle puts it in the tank. LOL. Even the lowly Lucas CAV or Stanadyne DB can be had up to 400cc but no major mods listed for the VE.
 

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Discussion Starter · #5 ·
I'd say 300 HP is kind of pushing toward the limits of a stock VE injection pump. One thing that should be known is which VE pump you have. The base 4bt road engines used Bosch part 0 460 424 055. That number tells you some valuable info. 0 tells you it's a complete unit. 460 tells you it's a distributor pump. The 4 tells you it's a VE pump. The 2 tells you the plunger diameter which is a very important number. In this case 2=12mm. Plunger size codes are as follows: 8=8mm, 9=9mm, 0=10mm, 1=11mm, 2=12mm, 3=13mm, and 4=14mm. So somewhere out there are VE pumps with 2 plunger sizes larger than was used on our stock 4bt. Heaven only knows where you'd find one. Back to the part number the next 4 tells you the number of cylinders. And the last 055 numbers tells you the application. I browsed a company list showing dozens of VE pumps and almost all were the 12mm plungers. Found no numbers for the 13mm or 14mm. I suspect those are quite rare. The other main inline injection pumps, A and P, can be built to staggering fuel levels. The A can be had up to 900cc, P3000 to 1100cc, and P7100 to 1700cc. That P7100 would about suck it as fast as the fuel nozzle puts it in the tank. LOL. Even the lowly Lucas CAV or Stanadyne DB can be had up to 400cc but no major mods listed for the VE.
I found the thread I was looking for: Got my VE flow benched! results inside!!!!!!

Bench test with his actual injectors: Got my VE flow benched! results inside!!! More than enough fuel for 300hp.

I can't easily see which size pump he had though. I'm sure it's in there somewhere. I think it was 12mm pump. I owned a vehicle with an 11mm VE pump for many years but never had the time to get it road-legal. It's just been sold.
 

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I did run across pumps with some of the smaller plungers but none with the larger ones. Would need a friend at Bosch to tell what application the 13mm and 14mm were used on. Might possibly be marine engines but those with VE pump were seldom high power. I had read some articles of people who had built 14mm pumps but they had very limited life. One seized up on the test bench. I could also be possible that the larger pumps were only on 6bt engines and no 14mm heads were ever available for the 4bt.
 

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Good info as always Dougal. Pretty much cements the notion that there's no need for anything other than stock injectors without a big set of compounds.

I'm surprised at your air intake number. I figured it'd be higher, closer to 600cfm.
 

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Good info as always Dougal. Pretty much cements the notion that there's no need for anything other than stock injectors without a big set of compounds.

I'm surprised at your air intake number. I figured it'd be higher, closer to 600cfm.
I think the airflow numbers look low because a lot of aftermarket garbage (pod filters, intercoolers, turbos etc) really inflate their CFM numbers beyond reality. I run a Donaldson cylindrical air-filter and they have true ratings which fit quite well. Proper air-filters start getting enormous.
 

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I promised this one a long time ago. I just tweaked some existing numbers to show what is possible.
Single turbo.

Calculations are done for a HE221 with 6cm housing. Other turbos below that will work:
HX30-6cm (44mm or 46mm intake versions).
HE221-6cm (7cm will do too)
TD04HL-19T doesn't have the boost capacity. Aftermarket wheels may help this.
Set the wastegate to 30psi which you should reach by a bit over 1800rpm.
Target A/F ratio is 18:1.

You'll need a large sized air/air intercooler. You need to take intake temps down from about 180C out of the turbo to about 50C into the engine. Your air filter and intake needs to handle 400CFM (30 lb/min).

Your injection pump will need to deliver ~180cc/1000 shots. All of them can do this. You can find this point by tuning in EGT or A/F or by asking a pump shop to set it at that point.

Peak boost and torque are expected around 1800rpm and peak power around 2500rpm. This gives you a decent power band for good drivability. Peak torque will be around 800Nm from a about 1700rpm to a bit over 2300rpm.

Peak crank power is expected 190kw (256hp) at 2500rpm.
Is there anything else that could add to this? A cam perhaps? Thanks for the post. This is along the lines of what I’m looking for.


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Discussion Starter · #14 ·
Cam will not be necessary for this power lvl. Especially if the turbo runs out of steam at 2300 rpm
Drop in torque isn't the turbo running out of steam. It's the burn speed of diesel and the drive pressure rising with RPM.
Can't do anything about the diesel burn speed, but a bigger turbine will give you more power at the expense of less low end torque.

It's all a compromise. I find if diesels aren't pulling strong by 1500rpm they are hard to enjoy.
 

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Drop in torque isn't the turbo running out of steam. It's the burn speed of diesel and the drive pressure rising with RPM.
Can't do anything about the diesel burn speed, but a bigger turbine will give you more power at the expense of less low end torque.

It's all a compromise. I find if diesels aren't pulling strong by 1500rpm they are hard to enjoy.
Lol, not all of us speak engineer as well as you do ;)
Some of us describe things how we feel and observe them, but it makes sense when u beak it down.
I totally agree, 1500 is almost half the usual speed people spin 4bts
 

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Lol, not all of us speak engineer as well as you do ;)
Some of us describe things how we feel and observe them, but it makes sense when u beak it down.
I totally agree, 1500 is almost half the usual speed people spin 4bts
Yeah it's about maximising power-band. Max power is usually set around 2500. Starting peak boost as low as possible is the best way to maintain drivability.
 

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Lol, not all of us speak engineer as well as you do ;)
Some of us describe things how we feel and observe them, but it makes sense when u beak it down.
I totally agree, 1500 is almost half the usual speed people spin 4bts
As a person who spent decades on the shop floor I learned that the single biggest factor that separated the "Useful" engineers from the ones that trended to be a PITA was the ones that could connect with the shop personnel was that they either started on the shop floor or had hobbies that required dirty hands and busted knuckles.
The "Dirty Engineers" spoke our language Dougal seems like what we would have been grateful to have on the floor with us on the tough jobs.
I for one have learned a VAST amount from him, the discussions that were over my head 5 years ago now make much more sense and the support I have received has given me the confidence to experiment as well as enabled me to focus my efforts where they matter most.
Seeing as there is no One Size Fits All package in the swap world we all will face many application specific adaptations so like it of not we are ALL engineers and we are lucky that the A Team has the time and ability to lift some of the fog for us.
 

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Well, I hope to find out. The engine is already on the transmission-- so don't expect an engine dyno. However, I do have a P7100 4bt with the HE221 6cm ( I think it is a 6) and a 4k spring and timing bumped. We will see what the seat of the pants meter says when it is all done. It has been a long 7 years getting it going...
 

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In all the HE221W turbos I've seen listed don't believe I saw one with a 6 cm2 turbine housing. Found 5 cm2, 5.5 cm2, and 7 cm2. Doesn't mean there isn't a 6 cm2 but don't know its part number.
 

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In all the HE221W turbos I've seen listed don't believe I saw one with a 6 cm2 turbine housing. Found 5 cm2, 5.5 cm2, and 7 cm2. Doesn't mean there isn't a 6 cm2 but don't know its part number.
IIRC the 6cm housing is for the TD04L but they interchange I know when I move to higher ground and needed to change the one I found was a MHI replacement part.
 
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