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How to turbo propane a 22re

68K views 81 replies 36 participants last post by  Blase 
#1 · (Edited)
I have had many people ask about my motor and I figured that I should consolidate it into one thread.


This is not a “how to do” but a “how I did” my turbocharged propane 22re motor. I am going to go over the things that I learned, did, and would like to change on this type of powerplant.


Powerplant


I started out with a 22re motor that I got out of a wrecked 87 standard cab. This is a standard high compression ratio (9.0:1) motor. Just for reference the 22r-te motor is a lower compression ratio at 7.5:1 (with 6 lbs of boost)


Turbo Type


I bought a new turbo from Cary at Propane Conversion Kits . He doesn't advertise them but runs them in his own rig and sold me one when I asked him over the phone. What I know of this turbo is that it is a Garrett T-3 and that it came off of a Volvo. What I dont know is the year or the type of car that it came out of. It has been fully rebuilt by a professional turbo rebuilder and the trim has been modified for optimal performance. It is built specifically for a propane powered 22r-re motor.





Propane kit


I also have a kit from Propane Conversion Kits . The kit is a EFI style. Not much more to say here besides great customer service and a product that is built for the application. Definitely not a forklift propane system.


Propane and turbo info


Propane is a 112 octane fuel in comparison to gas that is 87 octane. It weighs 4.2 pounds per gallon (lighter than gas) It burns cleaner that gas (leaves less carbon deposits) and extends motor life and motor oil changes. The energy density of propane is 91,690 BTU per gallon and the energy density of gasoline is 125,000 BTU per gallon. I thought this was interesting and took it from Wikipedia “ A high octane rated fuel, such as liquified petroleum gas (LPG), has a lower energy content than lower octane rated gasoline, resulting in an overall lower power output at the regular compression ratio of an engine run at on gasoline. However, with an engine tuned to the use of LPG (i.e. via higher compression ratios, such as 12:1 instead of 8:1), this lower power output can be overcome. This is because higher-octane fuels allow for a high compression ratio hence a higher cylinder temperature, which improves efficiency.”

Motors with turbos like high octane fuel since they are compressing air into the combustion chamber and need to overcome the lean condition that the extra air causes.

More from Wikipedia “ In addition to the use of intercoolers, it is common practice to add extra fuel to the intake air (known as "running an engine rich") for the sole purpose of cooling. The amount of extra fuel varies, but typically reduces the air-fuel ratio to between 11 and 13, instead of the stoichiometric 14.7 (in petrol engines). The extra fuel is not burned (as there is insufficient oxygen to complete the chemical reaction), instead it undergoes a phase change from vapor (liquid) to gas. This phase change absorbs heat, and the added mass of the extra fuel reduces the average kinetic energy of the charge and exhaust gas.”

The last statement is interesting because my mixer is set to run rich per Carey’s instructions. Also propane has a low boiling point of −42 °C (−44*°F) which makes it vaporize as soon as it is released from its pressurized container. This makes it a cold vapor ready to be mixed with air (no carburetor or other vaporizing device is required (like with gas) and is the reason for excellent throttle response.


How to make a turbo work with propane


Now this is a mechanical style of turbo. No computers or stand alone ignition systems. I will get into the mechanical distributor part in a bit.

This is a “blow through” type of system. This means that the fuel is ran through the turbo. Another style is the “blow by” system. This is when the fuel is picked up after the turbo. I am not going to talk about the “blow by” system.

Here is the A,B,C, one, two, three, of the propane turbo system. Air filter, propane mixer, turbo, throttle body, intake manifold and into the combustion cylinder. Of course there is charge tubes and elbows that tie this system together.

The reason this works is quite simple. The propane mixer is designed with a diaphragm that opens and closes with vacuum. As a motor creates more vacuum (air suction) the diaphragm opens to deliver the correct amount of propane per vacuum (mixers come in different sizes and have air-fuel adjustments on them). So what this means is that as the turbo begins to spool up and create boost (or more vacuum) the mixer opens up the diaphragm to allow the correct amount of fuel for the air entering the system. One could say that the turbo “tricks” the mixer into more fuel delivery.

Now one thing to keep in mind though. A volatile fuel mixture is flowing through the turbo, charge piping, throttle body and intake manifold. A engine backfire will cause a explosion in this system. I had this happen to me when I first fired my motor (timing on distributor was off) and I blew my charge pipe across the shop and against the wall. This is hard on the turbo and will usually damage the diaphragm to the point of rebuild.


Distributor


The reason that a mechanical advance distributor is needed is because of the way that the mixer mixes the air/fuel. There is no way that a stock Toyota ECU could (that I know of) be able to accurately sense what the air/fuel mixture is and be able to advance the timing at the same time correctly.


Oiling a turbo


One of the nice things about running propane is how clean the oil stays. It is really hard to believe until you see it for yourself. This means that you can go longer between oil changes and have less deposits in your motor/intake track (via the PCV valve)

Now turbos are oil cooled and lubricated so you should take some time in researching what type of oil you want to use. I went with a 10-30 Redline synthetic since it can withstand high heat (oil will coke in the turbo due to the heat after the engine and oil flow stops) but is still thick enough to handle the looser tolerances of a older style of motor.

There are three oil port choices on the 22r-re. But only two on the earlier R blocks before the 84. The first is the stock 22rte oil port. This is unmachined on non-turbo blocks. It is located right below and to the right of the block water drain plug on the driver side of the engine. It is shown here marked in white





IMOP this is a very poor choice to use as a oil feed. It would need to be machined of course but the kicker is that it is a solid vein that runs through the block and ties into another oil vein on the pass side of the block. That seems like a long way to drill with a very small window for mistake by me.

The second shown, marked in white





is the best overall choice IMOP. You can see the flat spot right on the oil vein and that would give a good place to tap and thread in a fitting. The best reason for this is that it is directly after the oil filter and would supply the turbo with filtered oil.

This is the easiest place to plumb in you oil feed line.





This one is a oil port directly behind the oil pump. It is located under the pass side motor mount. As you can see the oil pressure gauge sender is right in line along this vein. Both have the same thread pitch (28BSPT) and a adapter can be purchased to get it to -4. It was bought from LC Engineering but the link I had is now bad. I was going to put a oil filter in line to keep the turbo happy. I bought this from summit








And as you can see it wasnt going to filter anything. I bagged the idea since I became afraid if the filter was to fine or became clogged then I would starve the turbo for oil.

These are some pics of the feed line routing and how it is plumbed into the turbo.








The oil return is a very important part of the system. The oil is pumped to the turbo but after that it is gravity returned to the block. If the oil backs up the return line it will coke in the turbo. I have contemplated making a baffle system on my next build. It is very good practice to make the return line larger than the feed line with as straight of shot as you can get it.


This is a picture of a stock 22rte minus the turbo.


 
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9
#2 ·
In this picture you can see the stock oil feed line on the right and the stock oil return line and where it bolts to the block. It is a large flexible metal pipe that bolts to the block and returns through the block. This unmachined spot on a non-turbo block (84 and up) resembles Mickey Mouse ears and can be seen in my pic of how I drained my oil. One could machine this spot for a return if they wanted. It could be a better spot than mine since it is higher on the block and would help with side angles and oil backing up.

Now this is how I ran the return line on mine.





I ran a 5/8 high temp oil rated hose out of the turbo and welded a threaded bung into the oil pan.





Here is a list of what I bought for the oil feed and return line from ATP turbo





Water to the turbo


My turbo came with a water inlet and outlet so I decided to use them to help keep the turbo cooler. I have noticed that many people dont run water to them. I think it has to do with the added complexity.

This is a pic of the stock cooling system and how the water flows through it.





Here is a pic of how the water should flow through the turbo. Remember that hot water rises and if it is set in this configuration it will pull the cooler water up and keep circulating after the motor is shut off.





I started with two turbo specific parts. One is the metal section that sits in between the lower radiator hose and the feed hose to the water pump. The other is the feed hose to the water pump. I used these since the stock turbo water pump feed hose is made with a nipple to accommodate the stock CT-20 watering system. (these pics will help show the way that the lines are ran even though they are not in there final resting places)





I ran the water out of the turbo and brought the line around the block and plumbed it into the inlet radiator hose. This was a pain and quite the hardware store fab job. The local radiator shop said that they could braze a nipple in the radiator for me. I am still running a 2 core stock radiator but not very happy with it. My plan is to buy a turbo radiator (3 core and exact fit unlike the V-6 rad) and use the nipple already in it for the return line.





This is a problem that I have encountered. My water feed to the turbo leaks. I havent began to figure out this problem yet and I am sure is a contributing factor (non sealed cooling system) to my motor running at the 220* range on 90* days while out crawling with no air flow. On cooler days and in areas with more open trails (faster moving) it runs in the 190* range. I also drilled a small hole in the thermostat to keep the coolant flowing.





Water to the propane regulator


This picture is straight forward and to the point. I didnt need any of the EFI sensor stuff anymore so I found that these two spots let water flow. Water flows from the back of the water pump through the regulator and into the temp sensor cluster.





Take care when plumbing in new water lines. You do not want to have water flowing into itself or cutting off flow if plumbed into the heater system (turning on/off the heater)

This is a pic of a unused idea for my water flow in relation to the stock heater core water movement. You can see how easy it can be to stop water flow on accident.


 
#3 ·
Water to the heater


In the PNW heat is a must for the wife. This is the water lines for the heater core. Feed comes from the steel pipe that starts under the thermostat and wraps around the back of the block. You are unable to see the hose in this pic, just the steel pipe.





This is the return line that connects to the pipe that goes to the water pump inlet. The picture is looking straight up from the ground. You can also see the water outlet from the turbo.





This is the lines as they connect to the heater core. I made sure to add a filler to flush the core or add water (highest point in cooling system) if needed.





Intake Plume


The intake manifold needs to be modified. All but two holes in the plume must be plugged. One hole for the brake booster and the other for the PCV valve. Here is a pic of the injector holes plugged. I had some aluminum plugs made and Tig welded in.





The same for the holes on the side.





On a side note. The early model plumes turn down after the throttle body as the late model ones are straight. I was unable to use my early model plume since it made the turbo charge pipe connect with the radiator hose.


Exhaust Manifold


Now there are lots of options for exhaust manifolds. Some have the mount flange on the bottom like the stock 22r-te and others have a top mount. I have heard good things about SteedSpeed Steed Speed - Welcome to Steed speed performance inc. . I looked over a Dodge 5.9l Cummins manifold made by them and it was a CNC piece of art....

I used a stock 22r-te manifold as it was suggested to me by Carey. Take care with these manifolds though. They often have cracks in them due to a poor flowing turbo (stock CT-20) and the #3 - #4 ports being to close together.

Now I was stubborn when it came time to mount the turbo to the manifold. I was told to do it one way but it just didnt seem right to me..... Should have listened to the person who had done many before me... I will show you my costly and timely mistake.

The T-3 wont bolt up to the manifold (it will but bare with me here) so I purchased a adapter from LC Engineering (if it sounds expensive well, dont worry, it was)

This is the adapter. You can see how restrictive it was going to be.





So I did my best to match port them with a air dremel.





Now this is why all of that work and money was ill spent. The turbo needs to be rotated on the mounting flange. This allows room for the mixer/air cleaner on the air intake side and room for the coupler elbow on the air exhaust side (to intake manifold). Otherwise the exhaust manifold interferes with both as seen here.


 
#4 · (Edited)
Now what I was told to do and finally did was this. Rotate the turbo 45* so the air intake moves away from the motor. Two of the four bolt holes will be used. They will not line up perfectly but a quick ream with a drill on the turbo will make them match up (see why I thought this was a bad idea to begin with?) You can see how it is put together here.





I wanted a good gasket so I made one out of sheet gasket maker.
and sent it to Remflex Remflex Exhaust Header / Manifold Gaskets . They made a run of four for me. I told them of the application though and to keep one as they may have others want to purchase them. They said they would and gave it a part #.









Turbo Brace and Manifold Studs


Another problem that the 22r-te’s are prone to are the exhaust manifold studs stripping out due to the weight of the turbo hanging off the manifold. Although I didnt have this problem to start with I decided to just go ahead and helicoil them anyway (wasnt sure on the integrity of the aluminum threads). This is the size that you are looking for, Metric Thread Repair Kit Size: M10X1.25-12 Insert Part # # HEL-5543-10 . Napa part # is 7703020.

I also built a brace that bolts on from the turbo to the engine block.






Exhaust


The exhaust pipe is all custom made. I mostly used scrap that I collected from muffler shops.

First and formost, the exhaust flange on my T-3 is very close to a Chevy 2 3/4 tri-bolt. Just a bit of file work let it slip on.





I wanted as free flowing exhaust as possible. Turbos dont like to have back pressure so I went with a full on 3”. The bends ended up tighter than a shop could make so I had to hand make them.








Like the stock pipe, I made a bracket to bolt the pipe to the motor.






 
#5 ·
I ran the pipe at around 3’ for awhile. I was surprised how much the turbo toned down the noise with the pipe so short. You could also hear the turbo whistle very well also. In the end though I added more to the pipe. My skid plate trapped in the exhaust fumes and heat. My floor pan got to hot to touch! I put on a Morroso Spiral flow muffler. It had the least amount of internal resistance of a muffler that I could find besides a Glass Pack style (they jut dont last here in the PNW) I also ran the pipe out past the skid plate. The thing is super quiet now. My stock truck is louder.









Charge pipe and hose elbows


I used 2.5” OD exhaust pipe for the two pieces of charge pipe. This is a list for the hose elbows I used. I also suggest using appropriate sized T clamps. They have a greater clamping force than hose clamps

Throttle body to charge pipe: 2.75”- 2.5” 90* Charge pipe to charge pipe: 2.5”- 2.5” 60* Charge pipe to turbo outlet: 2.5”- 2” 60* Turbo inlet to propane mixer: 2.25” to 2.75” 90*









Distributor part 2


On a mechanical toyota distributor there are two vacuum ports. I plugged the first and used the second one. This is the port that moves the off idle advancement diaphragm in the distributor. I then ran the line to the throttle body. Make sure that the port you use gives vacuum (from the motor) while the throttle body is closed.








Throttle body upgrade


Some may have noticed that the throttle body looks a bit different than the stock 22-re. This is because I upgraded mine to a Supra/Cressida 5-mge model. The reason I did this was to enlarge the bore from 55mm to a 60mm.

If you are interested in this mod you can search “60mm throttle body upgrade” This is the link http://www.pirate4x4.com/forum/toyo...m-throttle-body-upgrade-pane-application.html


Wiring


The wiring is the same as a regular propane ran rig that has a Got Propane EFI kit . Just one wire to a solenoid that opens and closes a valve in the propane line from the tank to the regulator. Coils on a toyota are different from the carbed and EFI model trucks. I used a carbed coil.
 
#6 ·
How to set a internal wastegate (setting boost pressure)


This how I set the boost. First I will show the working parts and explain how they work. Then I will show how I was able to set it.

This is the internal waste gate. When open it equalizes the presser from the front to the back of the compressor fins.








The internal waste gate is moved by a adjustable actuator arm on the outside of the turbo. It is hooked to a vacuum diaphragm.





The boost is adjusted by the length of the actuator arm. In the above pic you can see that the arm threads in and out and also has a jam nut for its final setting.

The vacuum diaphragm has a port that a hose is hooked to and routed to the air exhaust side of the turbo. It is a gold colored nipple on this turbo.





I plumbed a T into this line and ran it to a boost gage.

This is how I set the boost pressure. I first started out with my gas shield bottle from my welder. I then used a vacuum gage and adjusted the pressure from the regulator to the wanted boost pressure.








I hooked up the turbo diaphragm to the welding shield bottle. I then just used my finger to feel for the waste gate to open when I cracked the bottle turn valve. This can take a few tries since the arm is adjusted by its overall length.






Steering arm modification


When installing the turbo I ran into a slight problem. The turbo sat about a 1/8” away from the steering rod. I knew that the motor would flex more than that and it would make contact when running.





My fix was this. I took two steering rods, a piece of straight rod, and a heim joint and made this.





This relocated the steering arm out of the way of the turbo.


 
#7 ·
Tuning


Now this is going to disappoint quite a few. I dont have any real tuning tips. The best way is to use a wide band o2o sniffer. I was told by Carey that 15.5 to 16 on idle and 10.5 on rev is a good place to be. I was also told to run the mixer 3/4 to the rich side (turn knob on mixer) and start with turning the air/fuel spring all of the way out and then running it in for minimal tension on the spring.

I had a backfire and blew out my mixer (started the motor with the distributor off one tooth) This ruptured the diaphram inside the mixer and the air/fuel mix wouldnt change no matter how much I messed with it. I called Carey and set him the mixer. He rebuilt it and set it to work great on his truck. I never messed with any of the settings after that.

When I had the rig on the dyno I was able to advance my timing up to 10* and still not have any pre-detonation under wide open throttle.



Toyota engine specs and dyno numbers for my turbo conversion


This is a list of stock Toyota engine specs. It will give you a idea on what a stock turbo truck will do along with other engines and how it compares with my set-up. These are all at the flywheel numbers though.





This is my trucks specs at the time of dyno.

Engine type: Junkyard 22re

Compression: 9.0:1

Mechanical mods: Supra TB, 3" exhaust with Morriso free flow spiral muffler, Dual transfer cases, 35" and 39.5" tires, with 5:29 gears

Garret T-3 turbo on propane 7psi boost

Tuning: Mechanical distributor and timing set at 10*

Dyno type: Dyno Dynamics

Hp and Tq: *35" tires *113 Hp and 138 Tq * Stopped at 4600 rpm
** * * * * * * * *39.5" tires 116 Hp and 130 Tq *Stopped at 4600 rpm



And this is how mine did. I did some research and I feel that the flywheel numbers on it should be close to +40 on the HP and +30 on the torque.






Dyno run on Krunch - YouTube
 
#17 ·
Its my understanding that the stock dizzy wont handle much over 10+ pounds of boost (may be 12 but I forget). After that you have to run a stand alone ignition system.

So yes, there is a need for one, but only at large boost pressures.
 
#15 ·
Any info on swapping the Efi coil/ignitor to the standard 22r coil/setup? (I havent looked into it as I plan to keep my Efi), but its a part of this swap
I thought about adding it for a minute.... but S canned it. My rig is a bare bones type of rig and I stripped out a lot of the wiring. Also it was a 86 and I wouldnt know if the same would work for newer rigs as I have never researched their harnesses. I figured that it would confuse many if I added in how I did mine since it is so minimal.

Start reading my build on page 12 and you will see how I did mine.

http://www.pirate4x4.com/forum/toyota-truck-4runner/731541-blueberry-krunch-12.html
 
#16 · (Edited)
Any thoughts on cooling that boost. nope
Well as stated above the pane boils (turns from a liquid to a gas) at -44*.

Not positive how cold it is once it hits the motor....... but my guess is colder than a inter-cooler could make it on a crawler whose airflow is next to none.


Also that is just makes a larger air/fuel mixture sitting around waiting to get burned...
 
#22 ·
I'll try to add stuff here and there. Stubs, take tha cap off the retard porton of the dist. It will advance with vacuum and retard with boost. Who needs fancy electronics? :beer: The stock ignition system will function past 22lbs of boost. I don't recommend that.:grinpimp: Use stock turbo plugs, factory cap, rotor, wire set. Factory!
 
#23 ·
I agree with Cary. I don't know why but Factory toyota plug wires work the best on toyota engines.

Cary, question. With head studs and a factory N/A (9:1 CR) bottom end, how much boost can we add before blowing headgaskets, rods, etc?

Sounds like you have seen short runs to 22lbs. Is 14 safe on a regular basis?

Leni
 
#32 ·
.

Cary, question. With head studs and a factory N/A (9:1 CR) bottom end, how much boost can we add before blowing headgaskets, rods, etc?

Leni
I was fine with a totally stock 250k+mi motor @ 7psi.........but......I went to 10psi:evil: and blew the head gasket.
Now with arp headstuds and a non-mls gasket I've been running 10psi with no problems. didn't want to push it any more with the tired bottom end:(
 
#29 ·
your thread title and the second sentence in this thread boggles my mind :flipoff2:
Well I was waiting for "that guy".... Looks like he finally spoke.....:flipoff2:

The main reason for the title was for search purposes.
 
#31 · (Edited)
When using a wideband(or narrow band for that matter) O2 sensor/gauge that was made for gas will you have to compensate for the different stoich. of LPG and gas?
i.e when the gauge reads stoich. 14.7, will it really be 15.5 on LPG(15.5 is the stiochiometric ratio for LPG) since it's actually reading the oxygen in the exhaust??:confused:
 
#36 ·
does anyone know this?? just trying to figure out where my lpg air/fuel ratios are:confused:
 
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