Originally Posted by ltn

I'm only a lurker. Thanks to you guys I have learned a lot about the IS. Since this video was found and posted, I will shed some light on the subject.

Like many of you I wanted MORE. HKS350 paved the way and I was convinced with the HKS kit. Like Jeremy(HKS350) stated, the kit runs extremely rich (10.0 AFR reading) and many christmas lights on the dash. So long time friend Jotech Racing out of Garland Texas was asked to help. With their many years of experience and being a HKS pro dealer, the FConIS was tuned to 10.9 (aem wideband) and 11.3 (motec wideband). He stated he can get more by going to 12.2 but stated there's the possibility of broken connecting rod since the motor actually spikes to about 400hp during shifts. Prior to the tune the car was baselined twice. Once in Houston in early June by Carboy (250whp). Then in July by Jotech (245whp). During the dyno's the temperature was 98 degrees Houston and 105 degrees Garland. Since not all motors are equal, my motor is on the weaker side. The kits boost is set to 5lbs. HKS stated they wanted reliability not top horsepower. We all know by now this is NOT the car to get if there is a desire for huge HP gains. With 5lbs., the gain is as shown in the video of 285hp. A 40hp gain from baseline, which is about right. Calculate in the drivetrain loss and that puts her right around 335hp at the motor. Given these numbers, my car either only putted out 295hp (not 306hp) at the motor from factory or she has lost HP being driven hard her whole life and reading 91k on the odometer.

Way before I took this journey, I believed I search to the end of the internet for another supercharged IS350 with some kind of information on numbers and dyno stats. I failed. So I just might be the first one to post the lowest supercharger HP numbers and a video dyno with stats.

Anyhow, the 285hp is just the supercharger kit with a TOM'S barrel exhaust and a successful tune. Next up is PPE Headers, HiFlo cats, and Midpipe. Will be happy with a reliable 300-310whp. She's a daily and track.

And yes, it is extremely costly to squeeze anymore out of an IS350. Sad to say, The IS250 crowd might repeat what happen with GS4xx and GS300, where the 300's started having unlimited potential to soar into the 1000hp+ numbers. Only time will ______ .

Thanks for lurking.

Originally Posted by HKS350

Around a month ago I got a few emails from the tuner at JoTech. I sent him my EXE.Dat HKS files I have on file for the FConIS. So pretty much I sent him my tune. I still have no issues, no CEL, drives like stock!

When talking to them they were having alot of CEL for random stuff thats causing the car to enter "limp mode"

I have not heard back from them. I gave them a ready perfect tune so we'll see if it was that issue or if the engine was damaged??????

Originally Posted by HKS350

Around a month ago I got a few emails from the tuner at JoTech. I sent him my EXE.Dat HKS files I have on file for the FConIS. So pretty much I sent him my tune. I still have no issues, no CEL, drives like stock!

When talking to them they were having alot of CEL for random stuff thats causing the car to enter "limp mode"

I have not heard back from them. I gave them a ready perfect tune so we'll see if it was that issue or if the engine was damaged??????

Originally Posted by mikellucci

HKS350 - does your FConIS use and interupt the stock o2 sensor feedback for A/F ratio or do you run a seperate wideband o2 (if ext. wbo2 where did you place your sensor?)? Thanks