2ZR Turbo Yaris

[atomic_hoji]

Awesome!

Definitely following this thread. Like many, also haven't done a turbo upgrade before, but also looking forward to learning along with you - and of course happy to help where I can!

When you say researching turbocharging have you been reading mostly online or have you picked up some good books? Just wondering as I have a selection of books on tuning and forced induction bookmarked for future interest - just curious what you've found as good resources.

When I was lining up the 2ZR swap for my car I had come across this kit and took a few, rough measurements and had also done some reading about the fitment with the Corolla and use of supercharging on the Lotus'. So, for the sake of discussion / second opinion:

My thought on boost is that the specs for the Lotus Cup 250 show it running 11 psi on the stock 2ZR internals. From the Toyota Nation discussions on Corollas that have installed the Turbokits kit it sounds like you're pretty safe if you stay < 8 psi and have a good tune. Starting with a conservative 6 psi or so seems like a good strategy.

I agree that you should (fingers crossed?!) be able to fit everything in behind - there is actually a reasonable amount of room back there! I had intended to move the ECM away from the factory location using the Corolla iM engine harness, but I think the stock Yaris' ECM is up high enough you'd be OK - worst case you might find that you need to run a turbo blanket or heat shield of some sort. Running the air intake and other piping on the Yaris vs. the Corolla will be a bit of a trial and error to see how much modification it will require to fit. Very interested to see how you make out with fitting everything in terms of firewall clearance and intake piping especially.

Regarding engine management - I don't have first-hand experience, but everything I've read (as I'm sure you have) is that to speak to a tuner that is familiar with the unit you're using; seems like you're headed in the right direction! While the standalone route is great, it becomes expensive fairly quickly if you want to control 2x variable camshafts and retain drive-by-wire. You also lose your daily creature comforts / controls that are available in stock ECM - although with a feature-filled standalone you can also add some cool stuff! The suspicion I have with the piggyback reputation for needing a reset is that the tune isn't resulting in predictable feedback to the stock ECM - i.e. the stock ECM works on the principle that it sees X air, demands Y fuel, and expects Z AFR. If your tune interrupts X air, Y fuel, and calculates new outputs - scales the MAF signal to expected range and demands fuel for the real (boosted) MAF signal - such that Z AFR ends up as what the stock ECM is expecting, then the stock ECM will be none-the-wiser. The problems arise when the stock ECM starts making STFT/LTFT adjustments which compound because of the piggyback correction and then settings start to drift. That's my take on it at least - I could be very wrong of course.. lol

You might find you're OK for fuelling on the stock system with running fairly low boost. That might be something to research and have in the back pocket, but see how the tuning works out? If your tuner finds you're leaning out badly because you're fuel limited then do the upgrade, but until then save the cash and see how the stock system works? If all you're changing is the fuel pump and not the lines in the system, fuel rail, etc.. it's easy enough to swap the pump out later. Have you had a look to see what the Lotus Elise with the 1ZR/2ZR is running for fuel flow? Might give you a comparison point.. A glance back at bookmarked threads on Toyota Nation, it seems they've been OK with the stock Corolla fuel system.

No idea about those mushy, smooshy autotragic transmissions.. But seems like from what you've said that the little U-series holds up pretty well. There are things you can do in terms of valve body upgrades to get a slushbox to handle more torque too if you find you're having transmission issues; never looked for the U340E, so not sure how common or expensive that path becomes..

Oi - that turned out to be long-winded... Never-the-less, looking forward to your updates as you make headway!

-- Adam

[06YarisRS]

Originally Posted by atomic_hoji

Awesome!

Definitely following this thread. Like many, also haven't done a turbo upgrade before, but also looking forward to learning along with you - and of course happy to help where I can!

When you say researching turbocharging have you been reading mostly online or have you picked up some good books? Just wondering as I have a selection of books on tuning and forced induction bookmarked for future interest - just curious what you've found as good resources.

When I was lining up the 2ZR swap for my car I had come across this kit and took a few, rough measurements and had also done some reading about the fitment with the Corolla and use of supercharging on the Lotus'. So, for the sake of discussion / second opinion:

My thought on boost is that the specs for the Lotus Cup 250 show it running 11 psi on the stock 2ZR internals. From the Toyota Nation discussions on Corollas that have installed the Turbokits kit it sounds like you're pretty safe if you stay < 8 psi and have a good tune. Starting with a conservative 6 psi or so seems like a good strategy.

I agree that you should (fingers crossed?!) be able to fit everything in behind - there is actually a reasonable amount of room back there! I had intended to move the ECM away from the factory location using the Corolla iM engine harness, but I think the stock Yaris' ECM is up high enough you'd be OK - worst case you might find that you need to run a turbo blanket or heat shield of some sort. Running the air intake and other piping on the Yaris vs. the Corolla will be a bit of a trial and error to see how much modification it will require to fit. Very interested to see how you make out with fitting everything in terms of firewall clearance and intake piping especially.

Regarding engine management - I don't have first-hand experience, but everything I've read (as I'm sure you have) is that to speak to a tuner that is familiar with the unit you're using; seems like you're headed in the right direction! While the standalone route is great, it becomes expensive fairly quickly if you want to control 2x variable camshafts and retain drive-by-wire. You also lose your daily creature comforts / controls that are available in stock ECM - although with a feature-filled standalone you can also add some cool stuff! The suspicion I have with the piggyback reputation for needing a reset is that the tune isn't resulting in predictable feedback to the stock ECM - i.e. the stock ECM works on the principle that it sees X air, demands Y fuel, and expects Z AFR. If your tune interrupts X air, Y fuel, and calculates new outputs - scales the MAF signal to expected range and demands fuel for the real (boosted) MAF signal - such that Z AFR ends up as what the stock ECM is expecting, then the stock ECM will be none-the-wiser. The problems arise when the stock ECM starts making STFT/LTFT adjustments which compound because of the piggyback correction and then settings start to drift. That's my take on it at least - I could be very wrong of course.. lol

You might find you're OK for fuelling on the stock system with running fairly low boost. That might be something to research and have in the back pocket, but see how the tuning works out? If your tuner finds you're leaning out badly because you're fuel limited then do the upgrade, but until then save the cash and see how the stock system works? If all you're changing is the fuel pump and not the lines in the system, fuel rail, etc.. it's easy enough to swap the pump out later. Have you had a look to see what the Lotus Elise with the 1ZR/2ZR is running for fuel flow? Might give you a comparison point.. A glance back at bookmarked threads on Toyota Nation, it seems they've been OK with the stock Corolla fuel system.

No idea about those mushy, smooshy autotragic transmissions.. But seems like from what you've said that the little U-series holds up pretty well. There are things you can do in terms of valve body upgrades to get a slushbox to handle more torque too if you find you're having transmission issues; never looked for the U340E, so not sure how common or expensive that path becomes..

Oi - that turned out to be long-winded... Never-the-less, looking forward to your updates as you make headway!

-- Adam

Hey Adam!

Thanks very much for the input.

Among other sources such as articles and forums, I've been working my way through Corky Bell's, Maximum Boost.
Still trying to get my head around such things as tensile and compressive forces in an engine - steep learning curve. If I'm interpreting it correctly, the potential destructive forces on engine mechanicals under boost are less than what I had assumed. Also, the focus on heat management in all aspects of the turbo system is strongly promoted as the leading way to ensure long-term durability. I think your suggestion about going for 6 psi is a very good one. I could always up it a smidgen if everything was in order and performing well.

Regarding fitment of turbo and piping, I guess I'll find out when I start. One of my colleagues has a '12 Corolla, so I intend to go out and do a quick comparison between it and the Yaris in terms of firewall to head clearance. It looks like the turbo sits low enough to get into that exhaust tunnel area, so I'm hopeful. Not sure what's directly behind that in the event that I have to get a big hammer out and make room. Yes, I've also been looking at turbo blankets for the turbine. I think that would be very beneficial.

I did speak with Jesse at turbokits.com regarding the capablity of my fuel pump. He had very positive things to say about the durability, capability and longevity of the pumps Toyota uses. He believes that I would not need to do an upgrade on the pump at the boost level I seek, but, again, recommended that my tuner advise me in that area.

Regarding the transmission, I purchased an ASE Mobilis research paper on the U340E and it rates the max torque of the trans at around 140 ft/lbs

A quote from Corky Bell:

"Will the transmission and drivetrain be adversely affected?

Very Unlikely. Consider that the drivetrain endures more torque in first gear from the stock engine than almost any turbo can produce in second gear..."

Maybe I'm tailoring the info to placate myself, but the above, coupled with claims by Monkey Wrench Racing that the U340E is good up to 250+ in turboed 1ZZ Celicas leads me to believe that I at least have a chance of good results. I did speak to a nice fella at importperformancetrans as they produce a high capacity U340E/U341E transmission. He, of course, definitely recommended a performance transmission for my turbo application, but he's in the business. When queried about what he would do to the trans, he mentioned a performance valvebody (I know these exist, as MWR sells them), different clutch material and metallurgical treatments (I think Tom discussed these when building one of his transmissions). I won't be trashing on the transmission, but I guess only time will tell how it holds up. I just have to stop worring about it and move on.

Jesse recommended that I do hook up the cams to the F/IC. He says that it would probably be possible to let the stock ECU handle the cams but the functionality is there and should be used. Timing is going to need to be pulled as boost increases, I believe. As far as where to tap/intercept the harness, it can be done close to the ECU connector. I figured I'd go 8 - 10" inches from the connector and that would put me closer to my glovebox, behind which I'll probably mount the F/IC.

BTW, I got my Fedex Tracking numbers today as well as a call from turbokits.com. Getting excited here!