Adding a turbo to a na engine

[BeerCan]

I have a question about adding a turbo to a normally aspirated engine.

I am looking at a piece of equipment that has a Kubota ~25 hp engine. Turbo kits makes a kit that adds a turbo. As far as I can tell it just adds the turbo without any other modifications. No injection timing changes etc.

What is the reality of this kit. Would just adding the turbo with no other changes really boost hp by a reasonable amount?

https://www.turbokits.com/tk-ventrac-4500y-turbo-kit.html

 

[ragtoplvr]

You have to add fuel. Otherwise will give very slight change.

Rod

 

[wwillson]

You have to add fuel. Otherwise will give very slight change.

If you don't add fuel, you could end up on the lean side and end up overheating internals.

 

[Jetronic]

it's a diesel, so leaner means cooler... but you need to add fuel or you will make less power, the turbo pressure isn't free.

 

[mattd]

You can’t run a diesel “too lean”.

If you dont add fuel you’ll likey notice little difference

 

[Pelican]

Turbo engines have beefed-up parts and added cooling to the pistons to counter additional stresses.
You can add a turbo to any engine, but you'll shorten its life span by a lot.

 

[blufeb95]

I didn't think you could really just slap a turbo on a N/A diesel, don't turbo diesels tend to have significantly lowered compression compared to their N/A counterparts even if they're running enough boost to effectively exceed the 22:1 or so compression of a N/A diesel.

 

[blufeb95]

About the only reason I could see for getting one of these kits if you're running the engine at high elevation.

 

[UncleDave]

About the only reason I could see for getting one of these kits if you're running the engine at high elevation.

and or a very power hungry pto accessory at the same time.

 

[thastinger]

you would probably find better help on yesterdaystractors or some other tractor specific board.

 

[wwillson]

You can’t run a diesel “too lean”.

If you dont add fuel you’ll likey notice little difference

We had a neighbor add a turbo to a John Deere 4020 diesel. They left the fuel pump alone and took it out and worked it against the governor and it overheated. The turbo kit company told them they had to turn the fuel pump up (literally a screw on the old mechanical fuel injection pump) to deliver more fuel. When they turned the fuel up, it stopped overheating and ran fine for many years with more power. I've seen a diesel overheat because it was running too lean.

 

[mattd]

I personally have never seen that on a Diesel engine. I’ve seen several melted down from too much fuel. Never, too lean.

Was that particular setup intercooled?

 

[wwillson]

Was that particular setup intercooled?

No, just the turbo blowing into the standard 4020 intake.

 

[ron17571]

I would guess that the pistons and rings would need to be upgraded. Clearances will be different. Engine timing and other internals may be different also. Otherwise, the engine will not last as long or very long.

 

[Kawiguy454]

Call them and ask them about the fueling, that is critical. That kit does 5-8 psi should give a good torque boost if the fuel is increased in proper ratio to the increase in air supplied. Too lean and there will be too much heat. Get fueling right and longevity wont be affected.

 

[Donald]

Intercooler?

 

[Donald]

Seems like the kits that JC Whitney sold decades ago to add A/C to a car without A/C.

 

[Jetronic]

We had a neighbor add a turbo to a John Deere 4020 diesel. They left the fuel pump alone and took it out and worked it against the governor and it overheated. The turbo kit company told them they had to turn the fuel pump up (literally a screw on the old mechanical fuel injection pump) to deliver more fuel. When they turned the fuel up, it stopped overheating and ran fine for many years with more power. I've seen a diesel overheat because it was running too lean.

Overheating from running on the governor I can believe. They weren't doing that anymore afterwards.

 

[mattd]

I too am still trying to wrap my head around the physics of that. I still don’t see you how you can run a diesel too lean. Fuel is control for everything, from desired RPM to full power. I don’t see how just by simply adding air with no more fuel will make it over heat. There are thousands of pickups with larger drop in turbos and the benefit is lower EGTS (more air to burn whatever left over fuel there is). None of them experience over heating. Granted, i this is going from NA to turbo, but still shouldn’t matter. Working against the governor as previously stated I can see that happening, but not just from increased air flow. There are even turbo kits for the old 7.3 IDI available for the non turbo models that you could bolt on with no fuel added, and none of those trucks had issues over heating or running hot. The benefit is reduced exhaust gas temperatures

If you have any literature backing up running a diesel too lean I’d love to see it.

 

[wwillson]

Overheating from running on the governor I can believe. They weren't doing that anymore afterwards.

No, farm tractors run against the governor for thousands of hours and don't overheat. That's what they are designed to do.