Rytzrap

I am sure somebody somewhere has already asked this, but here we go:

I came across a user: THP(if I remember right) via google search, from what I remember, they were able to crack the factory ECM and possibly the TCM to gain power with the possibility of a firmer shift. I own an '01 IS300. It is a very clean, very good running car, but I feel like the drivetrain mainly is just a piece of ****. I know a factory 2JZ-GE with a manual would have to out perform an automatic, but I dont want to go through the motions of installing a manual, plus I feel it would take away from the luxury aspect of the car. These cars seem VERY detuned. Low-end torque is bull****, doesnt really seem move until about "3rd" gear. I'm not looking for a full blown racecar. I've been there done that. I want maintain reliability, but acquire a little more efficiency out of the factory management that has seemingly been "left out". Has anyone performed this specific tune and have you noticed any substantial performance gains without sacrificing this cars already GLORIOUS fuel mileage or driveability?

mitsuguy

iTrader: (2)

the ECM is also the TCM... unfortunately, no one has found a way to change the internal tune with any Toyota vehicle (to my knowledge)

to be completely honest, the non-turbo 2jz is a piece of junk and the transmissions offered in any IS300 are junk too... there is no low end torque because there is no power in these cars to start...

the ECU is so picky on these cars that even with a piggy back like Emanage or AFC, no matter what changes you make, it "un-makes" and defeats any tuning you do, unless you go with a full standalone, which really isn't possible because you can't delete the factory ECU completely because it controls the drive by wire and transmission...

To be honest, unless you are happy with basic mods such as header and exhaust, you will spend a ton of money to do anything and all of it will hurt fuel mileage...

215 hp was just weak... on low boost my turbo'd one was making 320 at the wheels, and the car finally felt like it should from the factory IMO...

Rytzrap

What kind of boost are we talking? 7-8 lbs? I know that the pistons and rods differ from the setup in the GTE, though the heads "flow" better in the GE, I wouldnt mind boosting my stock setup, but at 120k it makes me a bit nervous. I would love driving around town on low boost with my foot out of the gas, I would imagine it would up my mileage slightly, but if I drive it any way like I did with my T-type then its going to be irrelevant. haha. What kind of ECM changes do you have to do with boosting the factory GE?

mitsuguy

iTrader: (2)

You could probably get away with 7-8 psi and a full standalone (AEM EMS or similar) so long as there is timing control...

the better flow in the GE head is very minimal, but definitely worth noting... turboing mine did not make it get better fuel mileage, in fact, it was about the same under cruise...

Rytzrap

This is all good information, I appreciate it bud. If you wouldnt mind, I would like a to shoot you a question every now and again. I promise not to load your inbox up, haha. I'm new to these cars and I am kind of weighing my options. Again, thank you!

selmerguy

I have been trying to get the source for the IS300 for a while and I really have lost faith in this happening. Its not EPROM or anything like that but it adjusts its fuel table based on the narrow band o2s very well. Very good ECU, very difficult to piggyback tune but not impossible. EMU does a good job because it actually runs the injectors and timing. The cool thing about the ecu is you can run some boost on a pretty much stock fuel system. I have been wideband tuning and logging mine in stock form for a few weeks and will be turboing and working on a inexpensive no CEL solution for mild applications.