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