Is EMS needed if tuning on dyno with wideband o2 sensor?

[debrucer]

If I have 550 injectors, the Lexus V8 AFM and tune on a dyno with a wideband o2 sensor, is a EMS necessary?

Reading the "What is fuel cutoff" article seems to indicate not.
That post says,

1. Replace your injectors with 550 cc injectors
2. Replace your AFM with one from a Lexus SC400 V8
3. Tune the car on a dyno with a wideband o2 sensor

Reading a Suprastore advertisement, implies I will need both.

Their description of the wideband o2 sensor includes the following text:

"FJO Wide Band O2 Sensor Kit

If you are serious about using the AEM EMS for controlling and making modifications to your Supra, then a good quality wide band o2 sensor kit is needed. "

Then they get into description of the EMS and say they really prefer a piggyback device... a bargain at about $700.

I presume it depends on how far past 13 lbs. of boost I'm going...

The AEM EMS sells for almost $2000. Seems like a lot of money. I know the answers are in this forum, or at least in this group. I've been unable to find them searching.

I would like to do steps 1, 2, and 3, and not make a fool of myself in an EMS, if possible.

Someone please point me in the right direction?

Thank you

 

[jetjock]

Well, with only 550s, Lex, and WB what are you going to tune with? That said you won't need the EMS as long as you don't go boost crazy. Not as good as a real piggy back but an airflow controller will do.

 

[suprahero]

As Mr. Jetjock said, you can't tune your car without some sort of tuning device. You can go to the dyno and see what horsepower you're making, and see what afr's you're running, but you can't tune it. You can do a piggy back like a SAFCII or something like that and tune your fuel, but if you plan on making more horsepower later, you're better off saving up for a Megasquirt or something that can control timing and fuel and a lot of other things needed to make high horsepower. I went with the ms3pro and it was about 1300.00 if I remember correctly. It will also do everything I need it to do. Good luck.

 

[debrucer]

Thank you both Jetjock and Suprahero. I read your reply on my phone and didn't know my SM password to respond. Then I spent a few hours reading online, and after seeing how well some people knew their cars goodies by name, got out the receipt box and have created a list. There are still bunches of things to do... and fuel management is right up there near the end. I will post something about where I am in general in an appropriate area. Thanks for this info... and incentive to get busy.

 

[debrucer]

The new Speeduino ECU project is coming along. I am building two versions which are referred to as ".03" and ".04", in the industry. They both are used as shields on an Arduino Mega 2560 microcontroller board. One is more suited to bench work, the other to applications. Basically, the connectors are different, and one has more prototype area. The chips for both boards arrived today from Digikey. My "Sigma Lambda Controller Free - SLC Free B" is scheduled to arrive today, too, so I have quite a bit of assembly to do. None of these pieces come with a case. The dash is out of my car an mounted on saw-horses. The wiring harness secured to a tall-stand light, and laid over a chair. I still have several design decisions to make with regard to how I attack the wiring. I can't see much use is working under the dash and trying to fit things where the original was... or using the glove-box solution, with wires that have to flex every time you open the box.

The dash gauge cluster is apart and several tools are connected to work with power and control for the digital dash. I have worked with about six different screens for ideas, and will make whatever wiring harnesses required. All of this ECU work, and progress, too, and the engine still sits unassembled. All of the engine machine work has been done except balancing, and I found a shop to do that now. Of course, rotating stock should include the clutch. I've got a stock clutch, and a "stage one" clutch", and if I'm not dreaming on HP, I should probably have a stage two or three unit. Without a controversy over stage definitions, going with the best clutch I have is probably marginal, and a short-term proposition.

I guess I didn't expect this much progress on the ECU. The cylinder head sits with cams off and valves ground but not fitted. There's one exhaust stud to be replaced there, too.

I obviously still don't know a hell-of-a-lot about tuning. I have purchased the full-editions of TunerStudio and the Megasquirt log viewer programs. They will be able to talk to the Speeduinos long before I have the engine back together.

My blog is a joke these days. I don't want to blog, I want to work on the car. I through something up there, trying to duplicate my real WordPress site with a "static" replacement... for $1.00 a month, world-wide, vs. the six bucks I pay now. So, the site that is at ToyotaSupraTurbo.com may one day become my car's page. Today, is is crap. Sorry about that