Adding a turbo to a TN65

[Wildcat Ranch]

I have been working on this project off and on for a week now and I am almost done. I got the turbo from a friend. I think its off a newer Subaru, but, he won't tell me. All the fittings were from the local auto parts center except for the water fitting going into the block, oil drain adapter and tube. I didn't turn up my injector pump and don't plan on it but the tractor is a lot more responsive then what it use to be. I am now waiting for my wastegate. It was suppose to be here today but now, I am hoping tomorrow.
I have 2 tabs to weld onto the piping for support and then, a little black paint! Also, I am not too happy with the way the rubber hose on the intake side is buckling and I might change it. Any suggestions?

I would like people to point out anything they would have done differently. My engineering skills kinda stink and I am always trying to improve them.

 

[skidsteer.ca]

I got the turbo from a friend. I think its off a newer Subaru, but, he won't tell me.

I didn't turn up my injector pump and don't plan on it but the tractor is a lot more responsive then what it use to be. I am now waiting for my wastegate.

I am not too happy with the way the rubber hose on the intake side is buckling and I might change it. Any suggestions?

I would like people to point out anything they would have done differently. QUOTE]

The install looks pretty clean with the exception of the intake hose, which likely has enough cross section to allow adequate air flow. The only thing I can suggest here is a offset made out of steel and a smaller piece of rubber on each end.

Most factory turbo installs have nice radiused corners on the exhaust, the first elbow out of the turbo looks pretty square. Turbos installations need free flowing exhaust because the turbo itself is enough of a bottle neck. Your elbow has a large diameter so restriction may not be that bad.

You should have provisions for a boost guage so you can see the net results of you labours. Also possibly a pyrometer to be sure you fuel curve is not to rich and runs too hot.

Now for some questions
Did you see this particular turbo installed on another tn65?
There are many configurations of turbos to balance the boost output properly to the engine.
If this is not right, either you will have no boost or the boost will be too high and will damage the engine.
Most turbo engines have lower mechanical compression ratios too.
Is this the same engine NH uses in my tn75?

I enquired about making my NH skidsteer ls160 into a ls170. It is the same engine, but the turbo model used a open chamber cylinder head to lower the compression. I would need to swap the head, and add the turbo, then adjust the injection pump.

I wish you luck, I hope you have more information about this combination then you initial post would suggest. Please let us know how it turns out.
Ken

 

[john_bud]

Three words,

Pyrometer, pyrometer, pyrometer.

You really must use one just after the turbo to tell if the engine is hurting it's self. 1200F is about the hotter you want to ever see. Short bursts of up to 1400F if the pistons have bottom cooling (your's probably don't).

I question the exhaust pipe outlet being close to what looks like plastic. That pipe is probably going to get hot, if not dern hot, maybe even really hot. You may be able to just wrap it with some exhaust insulation like the hot rodders use on headers.

If you can get a steel pipe with a double kink you may be able to use that with rubber sleeves on the ends for the inlet.

Overall, I would say it looks nice. good job.

jb

 

[MtnViewRanch]

Don't want to be a killjoy, but you asked and I'm telling. Pistons and piston coolers for sure and maybe the head should be changed also. Not to say that what you have done won't work. But to be sure of the longevity of the engine, internal parts most likely should have been changed.

I hope that it works out for ya.

 

[dieselgeek]

I tune a lot of turbo engines (gas and diesel) and I'm not sure why the thinking is that there will be more power with boost, but no additional fuel. Also, the fuel must come from either lowered opening pressure injectors, or higher pressure from the pump. The reason for this, is that you must get the "extra' fuel into the engine during the narrow timing window the diesel allows. Fuel outside the timing window, is the reason for black smoke. The injectors have a "closing time" and when this goes outside the usable timing window, black smoke happens.

There really isn't such a thing as "rich" or "lean" in diesel speak. Typical AFRs run between 70:1 and 7:1. The goal with turbocharging on a diesel is simply to reduce EGT temperature with increased fuelling. although, it's not necessary to go with new pistons or open chambers, that's only to take advantage of turbochargers that are most efficient at much higher PSI.

Proper selection of turbocharger requires careful examination of the compressor map, and both the hot side and compressor side Area:Radius ratios. I tune fuel injection, not select turbos, which is a science all it's own.

There should be no reason you feel "more response" if you haven't changed the fuelling, also what psi does that wastegate open up at?

A Pyrometer right after the turbo is an absolute must!! as is a boost gauge. You can get cheaper K-type thermocouples from Aircraft Spruce and Specialty... Also, looking at your pics, I'd suggest an Intake Air Temp gauge as without an intercooler, and a small turbo, you are probably raising your intake air temps enough to reduce power...
-scott

 

[SkyPup]

Once air is compressed over 8 psi an intercooler is an absolute requirement, otherwise all the turbocompressor wheel is doing is heating up the air to the point where it completely negates the increased air flow. At one bar atomspheric boost, most compressors have raised the air temp to oven temperature, about 350*F.

 

[Wildcat Ranch]

I will start off by admitting that I didn't do any research on this turbo but I now know its a IHI-Turbo, RHF5 VF40 off of a 06-07 Subaru legacy. I have uploaded charts for it below. I got this turbo in trade for some work I did for my friend, about $75 dollars worth.

The wastegate that was on it had a 10PSI spring but I ended up twisting the rod when I had it off, which, broke the seal. The spring is just to hold it closed for to time being. I barely go above idle if I need to move the tractor. I bought a new wastegate that has a adjustable rod, which has a minimum of 7psi.

I realize that I have to increase fuel to get more power but without the turbo, the tractor felt a little sluggish. Now it seems that the rpm's climb quicker, but then, maybe its all in my head.

The exhaust is 2 1/2 inch tubing. Do I need more then that?

I don't want to make it sound like I am a know-it-all, and i'm not but I have done reading online (reading, no hands on experience) on Powerstrokes, Cummins and Duramax's. From what I have read, going with a bigger turbo or going twin will lower you egt's.The VF40 is bigger then the factory turbo's on the TN75 by quiet a bit. Also, the VF40 is water cooled and oil lubricated where the TN75 only has oil. Without a intercooler, how many psi would be safe? I do plan on getting a Pyro meter and boost gauge, but if I only run 7-10lbs of boost, do I have to worry about it?

Sorry for all the questions and my stupidity, but all your input and advice has helped me a lot and is very appreciated.

Dan

 

[Coolnslo]

Not trying to be mean (really) but am curious and wondering:

What's the point of this? A few more horsepower at the risk of damaging the engine?
Are you prepared to pay for a new engine if it is ruined?
If you really need more horsepower, why not trade up to a tractor designed for it?
Your friend won't tell you where he got it? ???

I wish you luck. Your a lot braver than me and I have a life long experience working on things mechanical. I would never try what you are doing.

 

[Robert_in_NY]

Talk to your NH dealer about it. Ask them just how much is different between the TN65 and TN75. The engine is the same but the small bits are what matter. For what you are trying to do I would look at trading the 65 in for a 75 (either a TN or TT). Best of luck to you but this type of experiment has a huge chance of failure with very little gain as a reward

 

[dieselgeek]

Not trying to be mean (really) but am curious and wondering:

What's the point of this? A few more horsepower at the risk of damaging the engine?
Are you prepared to pay for a new engine if it is ruined?
If you really need more horsepower, why not trade up to a tractor designed for it?
Your friend won't tell you where he got it? ???

I wish you luck. Your a lot braver than me and I have a life long experience working on things mechanical. I would never try what you are doing.

ACtually, done right, it'll work out great for him. He just has a little bit of work left to go...


On the turbocharger, you can't really say "how much PSI" because each turbo is moving a different mass quantity of air for a given boost pressure.

For starters, I'd try to keep it as low as 5psi max until you can watch EGTs and manifold pressure.

In the case of the larger turbo, you might not have enough exhaust to spool it but it sounds as if it's spooling now, if you load it a bit?


How many cubic inches is your tractor, and how much horsepower? You can derive the lb/min mass airflow from the power numbers and get an idea how much exhaust flow you have driving the turbine, then you can look at the compressor maps above and plot your airflow characteristics on it. There's a website that'll do this for you.


As for the people wondering why do this, well, people gave me crap for putting Throttle Body Fuel Injection on a flathead six tractor - but in the end, it gets twice the fuel economy, runs 1000% smoother (HEI electronic ignition and EFI controlled by Megasquirt!), starts and idles at 450rpm, and the owner says he can't believe more people don't do the conversion... so, go with it!

-scott