90SR5-4runner

:monkey: Hi evryone. I am new to the YotaTech Forums and I have a few questions regaurding my 1990 SR5 4 Runner that I have just purchased. I bought the truck from a kid about a month ago and after driving it realized it had a blown head gasket. Fortunatley for me it blew to the atmosphere and not into the crankcase. So I pulled the head and discovered that the strange clatter that I had heard while it was running was the timing chain slapping against the timing cover. The head also had a horrible amount of sludge in it when I took the valve cover off. So after debating as to what course I should take on the repair or replacment of my newly aquired 1/4 million mile 22RE, I decided to pull the engine and tear it down. After doing so I discovered that half of both tensioners were no longer bolted the the block, but were in the bottom of the oil pan. Great!!! Here we go again. I am a big Ford fan as that is all that I have owned prior but do to the recent increase in the fuel costs and addition to the family, I have decided to go with a more gas friendly vehicle. I have built a few motors in my short stunt here on planet Earth. Anyways I decided to rebuild the motor and add a turbo as well. I dropped off my stripped block, crank, rods, new timing cover due to the chain wearing a hole into the water passage, and head to my machinist for the rebuild machining. I got the turbo on the mail today. It is a stock Toyota Turbo, I belive it to be a CT20. My current questions are, there is what appears to be a fuel line coming off of the Turbo that is attatched to a rigid flex looking pipe that I think goes to the passenger side of the block. What is the line that looks to be a fuel line? There is also a type of acuator that after some deliberation I think is a pressure relief valve. The way that it is hooked up, I think that if the Turbo developes to much boost, then there is an arm hooked to the pressure unit that opens a bypass on the exhaust turbine to lessen the spin on the compressor. I am lookin to see if anyone can provide me with a diagram of the parts of this turbo or can refer me to a book. I have searched and have not had a good return on information. Any and all help will be greatly appreciated. I woud be willing to write a Thread on this upgrade after I have finished to help any others attempting the same modification. Thanks again, Travis

dcg9381

The fuel looking line is an oil feed (the small one). The funky rigid flex looking pipe is the oil drain.

The actuator is called a "wastegate actuator" and you're right, it's a pressure relief system. It opens a little valve called a wastegate which by-passes the turbine.

A good link for turbo basics:
http://www.turbobygarrett.com/turbob...o_tech101.html


On a 22RE block you don't have the connections for feed or drain. You can put an oil feed/drain in a 22re block, but they won't work with that hardware.. You'll have to braze a connection for a soft hose (braded) to feed the oil pressure and work out some kind of system for a drain (usually straight to the pan).

The CT20 wouldn't be my first choice of turbo. It's expensive to rebuild, somewhat rare, and is a very small turbo. For the cost of a rebuild on a CT20, you can probably buy 2 small t3/t4 turbos.


You can't just bolt a turbo on to any old motor. Might want to ask your machinist about it. If everyone could bolt on a turbo and end up with a more powerful and more efficient motor, I think most of the major manufacturers would be on that train already.

Bolting a turbo to an otherwise naturally aspriated motor requires careful tuning. It can be done, but in most cases the a motor with a turbo has special pistons and a specific (lower) compression ratio to prevent some of the nastiness that can occur when you force a bunch of air into a motor.

Rick @ Fullboogie.net has been very successful putting a turbo on an otherwise stock 22RE and keeping it together for a long time. You might want to ping him about tuning a stock 22re and adding a turbo. In stock form, even with mild boost you have to be very careful - otherwise you'll reduce your new motor to a pile of scrap metal.

The stock ECU can't be modified via flash like so many of the latest import rockets. This means you have 3 options:
1) Accept the limits of the stock ECU and run very mild boost, slightly larger injectors, or a combination of both.
2) Find a piggy-back system that works with the 22RE.
3) Replace the ECU with something aftermarket - FAST, megasquirt, and SDS all come to mind.

If you really want to build a turbo motor, consider dropping 22RTE pistons into that setup. It'll lower your compression down to a level "normal" for forced induction. They don't cost any more than stock 22RE pistons.

90SR5-4runner

Hi dcg9381, I appreciate the response. I figured that was the waste gate but since I am new, I wanted to make sure. I informed me machinist that I was going to install the smaller turbo that I purchased when I dropped it off to him, and he said the same thing about the pistons. He is going sonic check the block, bore the block .020 over and by a set of Turbo pistons to match. He is going to resize the rods, deck the block with the new cover installed and mill the head and install new exhaust valves. New bearings are also on the list along with new freeze plugs. I see that there is a blank plate on the passenger side of the block where the drain back line for the oil runs. I am gong to drill a drain hole and tap to bolt holes. The feed galley from what I understsand is at the back of the block on the passanger side and has to be drilled virtually all of the way through the block to the other side. My machnist also showed me an alternate galley that I can drill that is next to the oil filter on the right side of the block. He recomended using this feed and routing the feed pipe around the back of the block in a similar fashion to that of the EGR and large coolant line. I am really not looking for an extremly large amount of increase in power, I was able to pick this turbo up realatively cheap, and am going to give it a shot. I have read that the factory EFI unit will handle the stock Turbo as the boost is around 7psi. Apparently the ECU has the ability to span the spectrum of the smaller Turbo and the Injectors will sufice also. As far as the waste gate goes, if turning it by hand, how much resistance should there be in the mechanism. It seems awful hard to open to me. I do not know exactly how much air is generated by the Turbo, but in order to open this valve, it seems that with the way the valve is opening it would need to be a alot. Also the crossover pipe from the turbo has two tubes attatched to it with old rubber hoses on them. Are these for routing Vaccum lines or some other function as the oil lines obviously are run down to the side of the block and would not be up in that area. Also on the hub of the Turbo, in the center in between the Compressor and the Turbine, there is on one side what appears to be an intake and an outlet on the oposing side of the housing. I can look right through it. Next question, what is this for? I am guessing water as I can't come up with anything else that would be beneficial and by the corrosion present. Last but not least, I am going to do some research and find out if I can put a Larger turbo on my new motor down the road if I add an aftermarket ECU and larger Injectors. I would think that as long as the boost isn't too much and doesn't cause the engine to detonate to death, I should be okay. I also plan on installing an intercooler also. Thanks again for any help in advance and thank you again dcg9381 for your help. I'm off to work, Travis

dcg9381

Travis - you might email me directly at dginther@gmail.com.

I'm a bit leery in regard to using factory EFI with a turbo application. Just to be sure, I'd have you call the tech line at LC engineering and ask them what the limitations of the factory EFI are in regard to turbos. If you do run factory EFI you should *absolutely* put a wideband in.. I've seen several people melt their setups running turbos.

Note, that you're going to end up with a motor that is close to factory 22RTE compression (a little higher) and 7psi limit on boost. Your results are at best going to be the same as a factory 22RTE motor.. Which is a slight improvement over stock.

Again, I'd highly recommend another turbo over the ct-20. The CT-26 comes to mind. It's common, it flows better, and it can bolt up to the toyota turbo manifold with minor modification.

Oil feed: On the passenger side, there is a plug behind the passenger side oil mount. I believe the threads are M10x1 (off the top of my head) - please confirm - anyway, this spot is pre-tapped as an oil feed. Alternately, you can "T" off of the existing oil pressure sender. I have some photos of these spots if you need them.

For a drain, I recommend drilling the very top of the oil pan and brazing on appropriate connector. Make sure you use a line that is OK for oil and hot temperatures.

Wastegate: The factory wastgate opens between 8-9psi. The only way to really test it is to hook it up to a pressure source and notice when it opens. Wastegate actuators can go bad... I had one cost me a head gasket, so it's important.

The CT20 is water cooled.. Water cooling is required with this turbo and you'll need to modify your heater line as well as provide a return to the radiator.


I need photos to answer your "what is it" questions.

Justin311

Did you do this motor build yet? If not, you really ought to put forged pistons in there while you're rebuilding. They will cost you a bit more up front, but allow you to run your setup to the limit without causing catastrophic engine failure. They will tolerate a moderate amount of detonation prior to failing, while stock toyota pistons will generally handle nearly nothing before they explode.

Either way let us know how ti turns out, I'm semi-planning to add a small T3 to my existing 192k mile 22RE and see how long I can hold it together

90SR5-4runner

Still working on this project. I have got all of my engine and parts back from my machinest and have started to assemble the engine. I will post more and more as I get closer to ignition in the vehicle and will go over the tuning process. For now I have included some pictures of the new block, Pistons and rods. Notice the deep dish in the pistons. Definatley going to lower the compression ration a bit from stock. So far I have used Plastigauge to check all of my oil clearances for my mains and rods and am absolutely impressed at my readings. Both the mains and rods are at .025mm, which is the minimum for a 22RTE. Plastigauge is a very simple measureing device and if anyone is unfamiliar with it and wants to learn more please ask and I will explain what it is.

90SR5-4runner

90SR5-4runner

Last but not least here is a photo of the block after the machine work was done before I installed the pistons. Also i have included a pic of the oil return from the turbo to help show what I was talking about earlier. Agin look at he shape of the flange and the bare spot on the block and notice they match.

Justin311

As opposed to that stock oil return you may consider a gasketless AN style fitting. Using toyota proprietary parts when you don't have to only complicates repairs in the future. I make aftermarket turbo oil line kits for other toyota blocks and always make sure to do away with the OEM parts in the case one of my customers breaks down on the highway somewhere and doesn't have a toyota dealer nearby

90SR5-4runner

Whats your email? I am interested in your product. Thanks, Travis

Justin311

Justins311 at hotmail.com

Bill

That's a purdy block

I'd defonitly reccomend not using the stock return line, if only for ease of routing. I'm currently working on using a T3 off the stock manifold(using an adapter), and because the turbo is mounted so close to the return port, it makes conecting the two(with a good flow angle) very difficult.

If you have to tap something, you may as well tap the oil pan. You're going to have to do something custom for the feed line anyways, so it wouldn't be that much more(if any) work to do it to the return.

Good luck, and defonitly keep us updated.

dcg9381

Tapping the pan is a good option. Depending on how you are mounting the turbo will determine how useful the stock return is.. The higher the turbo, the more useful the OEM return is.
You can adapt it to an AN style fitting with a little brazing.... The stock return isn't likely to fail.

Justin311

Any gasket is subject to failure. Any time I can go to a gasketless fitting I assume higher reliability: AN oil and water fittings, V-Band exhaust pipe/turbo fittings and Wiggins Intercooler/Air Vacuum hose fittings. You will notice all high end automotive applications (race teams, etc) use gaskets as little as possible

Bill

It would take a lot for that particular gasket to fail though. It's a gravity fed return...blowing the gasket would be quite the sight.

Justin311

You don't "blow" oil return gaskets. They fail from heat and decay (particularly heat in turbo applications, especially on vehilces that are used in low airflow situations, such as off road). I've got an entire box of low-mileage oil return gaskets I have pulled off customers cars that failed....I'll sell them all to you for only $5 ea, should be as good as new since they never see any pressure

90SR5-4runner

Hey everyone, I will have some more pictures up later today of the latest progress.

90SR5-4runner

Hi Guys, I am selling this project as I have aquired a 67 Ford Pickup with a 351 Cleveland and am out of cash. The turbo project is so close to being done, it ia a great opportunity for someone out there. It is on eBay 140170865072, Thanks, Travis

90SR5-4runner

Oay I am keeping and finishing the Turbo. I was able to raise some extra cash and no longer need to sell the Turbo set-up. I am glad as I really have put a lot of work into it and was bummed to let it go unfinished. I have assembled almost the complete motor now. I bolted the used factory turbo exhaust manifold on and it cracked in the center where it had been repaired- not a good job. I plan on repairing it correctly. I then ran into a problem with the turbo housing hitting the water pipe on the left side of the block that runs next to the block. If I keep the stock manifold then I am going to have to cut the water line and re route it with a flexible line around and away from the turbo. I still have to have a supply line and drain line made for the oil feed/return but am planning on using something from Earl's line. I also have run into the a problem with the existing EGR feed tube that bolted to the stock exhaust manifold. I have no where to bolt it now and am going to need to figure something out. I also believe that there is a sensor or vaccume switch that was on the originall manifold which is not on the turbo one. Again I have to figure this out for California SMOG. Anyways I will post some more pictures for those who are interested and keep everyome posted up to D day. and hopefully that won't be destruction day!!!!! I will post some pics soon, Travis.

90SR5-4runner

Here are a few pics for now. Notice the cracked area on the manifold.