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      11-19-2006, 01:15 AM   #1

Drives: X1, 335i
Join Date: Sep 2006
Location: SF Bay, CA

iTrader: (0)

Thumbs up Take 5: Vishnu 335i - Finally tested the Vishnu Stg 1 "kit"

Until now, we've done all our tuning work on my personal 335i. It was one of the earliest cars to the dealer. It never had its ECU updated with the programming update. And it saw a lot of the trial and error process during the tuning adventure. Everything from the boost control solenoid we used to how the Xede was installed as all custom one-off.

Today we finally had the opportunity to install the "kit" version of the Xede on a customer's car (imsambeen). This means that the Xede was installed right next to the ECU, under the ECU cover, away from prying eyes. There was absolutely no wire cutting, drilling or anything nonreversible involved. The Xede installation process itself took about 15 minutes.

Yesterday, Sam drove up from LA. The poor guy left LA at 2AM and meet up with me at the dyno shop in the morning. Having recently taken his car to the dealership for the ECU update, we were very curious as to how it would fair, in stock form, to my non-updated 335i (when it was stock, of course). The results varied between 264-270whp and 283-285lbft. This was 7-10whp and 5-6lbft less than my personal car. The differences are reasonably small and could possibly be accounted for by statistical variance. Or the ecu update is just a bit more conservative. Regardless of lower numbers or now, we're here to tune it! Not to pout over low baseline numbers

After the baseline dyno result, the work began. One of our fabricators built a full dual 2.5" exhaust. Just like the one on my car except that it had a X-pipe integrated in it (customer requested it). Sounded and looked nice.

The next morning, the Xede "kit" was installed. Then the tuning began. Running the same very Xede map that I run in my car, Sam's 335i put down 325whp and 350lb-ft of torque. Real close to what my car did. After some custom tuning, we got it to 330whp and 357lb-ft of torque. Just 3-4whp lower than mine. I suspect this is attributal to the X-pipe which does introduce some exhaust backpressure/turbulence compared to a fully divorced exhaust set-up. But for a car that started off making only 265whp and 283lb-ft of torque, I"m really happy with the results. Here the are:

Sam's 335i Stock Vs. Stg 1 (Xede and exhaust) [pls note that hp and torque axis are scaled differently]

One thing we found out during the testing is that non-Sport packaged cars wont rev out all the way to 7000rpm in 4th gear due to the lower max speed limiter. This is why the dyno graph only goes up to 6300rpm. Just gotta take my word for it since the bottom of the page got truncated by the printer

Just in case you want to compare Sam's Stg 1 car to my personal Stg 1 car (with sport package and higher speed limiter), check it out...

Sam's Stg 1 Vs. Shiv's Stg 1

Like mentioned earlier the only hardware difference between the two cars is that Sam's car had an X-pipe joining both exhaust pipes together whereas my exhaust is completely divorced all the way from turbo to tip. I suspect this is why Sam's car makes slightly less top end power. Although it's really hard to notice on the road

We have two more customer cars to tune this upcoming week (Xede only, no exhaust) and will report the results as they come in.


Last edited by OpenFlash; 11-19-2006 at 02:48 AM.