just installed cat bypass pipes - dyno results
06-22-2005, 12:00 PM
#16
Three Wheelin'
Akolodesh, don't get me wrong. My intentions are not to challenge you or jinx you in what is obviously a favorable mod but I just want to learn for my own knowledge how this is being accomplished with no faults (based on my somewhat poor understanding of how the OBD II systems operate).
06-22-2005, 12:03 PM
#17
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No problem whatsoever Alon. I am glad you are provided some critical analysis of this mod. It got me thinking about it and follow up with my mechanic about the potential issues. Keep it coming - the more information we can come up with, the better.
06-22-2005, 12:07 PM
#18
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Alon,
I also spoke with Steve Weiner at Rennsport before changing over to the Cat bypass, since he did my chip reprogram. He said no need to do anything to the chip with this mod.
I also spoke with Steve Weiner at Rennsport before changing over to the Cat bypass, since he did my chip reprogram. He said no need to do anything to the chip with this mod.
06-22-2005, 12:38 PM
#21
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Alon,
I found that the ECU reprogram helped to give a more "robust" driving experience. What do I meam by that word? Basically, that I could feel a "seat of the pants" difference in the 4000 - 6000 rpm range that makes drivng more enjoyable. I don't think there is enough of a difference to drop more than a second on the track. I would do it again as there isn't much on these cars that can be done for under a $1k that increases horsepower in any significant way.
I found that the ECU reprogram helped to give a more "robust" driving experience. What do I meam by that word? Basically, that I could feel a "seat of the pants" difference in the 4000 - 6000 rpm range that makes drivng more enjoyable. I don't think there is enough of a difference to drop more than a second on the track. I would do it again as there isn't much on these cars that can be done for under a $1k that increases horsepower in any significant way.
06-22-2005, 12:43 PM
#22
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Tom,
I have heard bypasses with supercups and it is not for the feint of heart!! Even with the maxflows its pretty intense. I think the RSRs would sound amazing with the bypass pipes.
I have heard bypasses with supercups and it is not for the feint of heart!! Even with the maxflows its pretty intense. I think the RSRs would sound amazing with the bypass pipes.
06-22-2005, 01:19 PM
#24
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Originally Posted by TheOtherEric
Alex, what was the effect on midrange torque? I can't tell from the graph.
Eric, I tried to increase the picture a bit - see if this helps.
the third pull (blue line) didn't lose anything significantly on midrange torque. The fourth pull (red line) lost a bit but also had the better max number (224.64) than either of the pre-cat bypass pulls (219.00 and 222.12). Pull three (1st cat bypass pull) had the best torque number at 225.90.
06-22-2005, 01:47 PM
#26
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Originally Posted by 95 C4 993
any issues with passing emissions?
06-22-2005, 01:59 PM
#28
RL Technical Advisor
Originally Posted by Alon
Thanks, that's amazing and goes against my understanding of how the systems work. Not to doubt you because you've obviously taken the steps necessary to prove their worth but I'm a bit confused by how this can actually happen without ECU programming. You've inspired me to look further into getting these in the near future.
You are correct sir; the CE light will illuminate from secondary oxysensor codes unless some things are done,......
I had a conversation with Alex's shop owner (Yuri) about that several months ago to aleviate that.
06-22-2005, 02:03 PM
#30
Three Wheelin'
OK Steve, that's what I figured all along. I'll contact you for your services if I go ahead with this mod. Thanks for confirming what I was hoping was not my imagination or usual incompetance and speaking out of my ***