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Old 01-08-08, 09:38 AM  
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Default Re: Harman Motive's 2008 STI

Baseline Dyno Testing

233WHP and 240TQ.

This is inline with 2004-2007 STIs on our dyno. No real surprises, although you can see the extremely lean AFR held until 3000RPM by the stock ECU. Boost was 15psi peak and held pretty steady until 6000rpm. AFR were 10.5:1 10:1 from 3000-7000 rpm.

HM Stage 1 Tune (Prelim)

We received a new Cobb CAN Accessport and Beta Protuning software last Friday. Big thanks to Cobb for getting this done so quickly! The software works perfectly, especially for a BETA version. Needless to say, as soon as this arrived I was on the dyno and the road testing

240WHP and 260TQ.

The only performance modification on the car is the Cobb Accessport w/ Harman Motive tuning.

I'm pleased with the results of our initial Stage 1 tuning. I raised the boost slightly (15.6psi peak), dramatically altered the timing map for smoother/more consistent performance, and adjusted the fuel map for more stable AFR of 10.8-11:1 from full boost to redline. I eliminated the delayed richening of AFR present with the stock tune.

I should note that I didn't spend all that much time on the dyno. After driving the car at the track and about 800 miles of commuting, I decided to focus my attention on the lackluster driveability and poor throttle mapping of the stock car. I spent days tweaking the throttle mapping, desired torque tables, and closed/open loop delays until I felt the car started driving the way it should.

In the process, I completely reprogrammed the SI drive. Currently, the S setting is similar to the S# stock. I decided to leave I mode alone. The new Harman spec S# is my favorite, although it is pretty aggressive. I feel that that the adjustments to SI-drive have really improved the car and it now drives much smoother and feels WAY WAY faster (surprising given the modest power gains).

The car no longer bogs below 3000 rpm and gone is the choppy on/off power delivery between 3000 and 4000 rpm. The car also pulls smoothly to redline (now 7100rpm).

I will be getting the car back on the dyno for some more power testing as well as some series AVCS exhaust/intake timing development. I hope there is some more power and spool available here, but we'll have to see.

HM Stage 2 Brake Upgrade

Immediately after the last track event, I knew we had to get a brake upgrade on the car. As with previous STIs, the weak braking is primarily due to the pads, lines, and rotors not the calipers. As such, you can perform an economical brake upgrade that gives you near BBK performance.

Our Stage 2 package consists of:

Performance Friction 2-Piece Rotors
Ferodo Brake Pads (DS2500 recommended)
Harman Motive 08 STI SS Brake Lines
Motul RBF600 Fluid

Braking performance was greatly increased with this setup. The lines and pads really do a number on the feel, you now get positive engagement as soon as you touch the pedal. Furthermore (and most importantly), fade has been greatly reduced.

I boiled the fluid bone-stock at Buttonwillow raceway on the FIRST session. Even after replacing the fluid with Motul, the brakes continued to easily overheat. This is at a track that is NOT very hard on brakes, and furthermore, I wasn't pushing the car. In my opinion, a brake upgrade of some sort is completely necessary on these cars.

HM Tail-Light Film Kit

I knew we'd have to get this done as soon as I saw the 08 WRX. The stock tail-lights on this car really ruin the back-end in my opinion.

We have these available in red, smoke (light), and black (dark). These are 7 piece kits: tail-lights (4), center brake light (1), and lower markers (2). It uses the same amount of material to make this a 4-piece or 7-piece kit, so you will get all 7 even if you don't want to use all of them.

These are overlays, so if you get the red, all of your lights will light up red. The smoke color allows the original light colors to come through well. The black mutes the colors more, but you can still tell what is shining through.

What's next??

We are finishing up our catback STI exhaust in the shop right now. It's a pretty nice lookng piece if I do say so myself. We decided to build a quiet system, focusing more on tone than volume. In California, this is quite critical. We are also doing some interesting things with the tip-design, can't wait to show you guys.

This will be combined with the downpipe design we finished last month (bell mouth, stainless 3" w/ cat). I'll be working the full Stage 2 treatment as soon as these are on the car.

We are also working on a cold-air intake for stock location turbos.

And finally, we will be installing our full GT3071R Harman Motive rotated turbokit on a customer's 08 STI starting next week. We'll be doing our prototype FMIC and a host of other goodies as well. I'll be sure to keep that documented

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