So I drove a Rotrex on Sunday at Buttonwillow...
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I know I don't post much here, but I wanted to chime in and say a couple things.
1. damn.
2. will and andrew, congrats. That's really fast. I think my car has probably better throttle response than 99% of turbo cars out there. But there is definately a difference between that and cars with instant throttle response.
3. I've lived outside of California too long. My records are going to fall. Congrats in advance for doing it. I'm pretty sure it will be a combo of the people and cars in this forum...
Matt
1. damn.
2. will and andrew, congrats. That's really fast. I think my car has probably better throttle response than 99% of turbo cars out there. But there is definately a difference between that and cars with instant throttle response.
3. I've lived outside of California too long. My records are going to fall. Congrats in advance for doing it. I'm pretty sure it will be a combo of the people and cars in this forum...
Matt
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Joined: Jun 2006
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From: Republic of Dallas
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Slightly bigger runners
Slightly more plenum volume
TB has less obstructed flow to plenum
No VICS or VTCS
Might guess it makes a tad more power. Won't know 'til March or so though. Moving to new shop in 4 weeks.
Pic borrowed from MX5Cartalk.com (Australia). Also seen in Japan, UK and EU.
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Joined: Jul 2005
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TPS based boost control is no secret. Virtually all OEM turbos have some road speed or TPS parameter controlling the boost solenoid. To control it very precisely, you really need a full PID control but most DIY'ers do it with a PWM map. ..
It's handy on a turbo set up that will exhibit PTFB (Part Throttle Full Boost). PTFB is kinda fun on a street car where you barely touch the throttle and go blasting through traffic. On the track and autocross course, it's damned annoying since you are trying to control tire slip angle with torque, and it has a mind of it's own. More of an issue on the track where you want to fine tune slip angle on long constant radius turns.
It's handy on a turbo set up that will exhibit PTFB (Part Throttle Full Boost). PTFB is kinda fun on a street car where you barely touch the throttle and go blasting through traffic. On the track and autocross course, it's damned annoying since you are trying to control tire slip angle with torque, and it has a mind of it's own. More of an issue on the track where you want to fine tune slip angle on long constant radius turns.
One of the nice things about the AEM is you can use a 3D MAP of target boost, with TPS and RPM as the axes.
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Joined: Oct 2009
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From: Los Angeles, CA
You can also run an adjustable pressure relief valve inline to your MBC to control boost onset.
DIY-Boost-Control
DIY-Boost-Control
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Joined: Jul 2005
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TPS based boost control is no secret. Virtually all OEM turbos have some road speed or TPS parameter controlling the boost solenoid. To control it very precisely, you really need a full PID control but most DIY'ers do it with a PWM map. ..
It's handy on a turbo set up that will exhibit PTFB (Part Throttle Full Boost). PTFB is kinda fun on a street car where you barely touch the throttle and go blasting through traffic. On the track and autocross course, it's damned annoying since you are trying to control tire slip angle with torque, and it has a mind of it's own. More of an issue on the track where you want to fine tune slip angle on long constant radius turns.
It's handy on a turbo set up that will exhibit PTFB (Part Throttle Full Boost). PTFB is kinda fun on a street car where you barely touch the throttle and go blasting through traffic. On the track and autocross course, it's damned annoying since you are trying to control tire slip angle with torque, and it has a mind of it's own. More of an issue on the track where you want to fine tune slip angle on long constant radius turns.
One of the nice things about the AEM is you can use a 3D MAP of target boost, with TPS and RPM as the axes.
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William enjoying a little Kraftwerks Rotrex power oversteer coming off the skidpad at Streets of Willow CW today. Oh yeah, we reset the absolute lap record for Miatas at 1:22.830
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Very cool to be seeing times being dropped further and further
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Last edited by emilio700; Jan 13, 2010 at 09:35 PM.
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Joined: Jun 2005
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From: Fake Virginia
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but had too much rear down force, had to keep cranking up the rear wing. center of the wing is actually pointed up 2 degree in that picture. doing that, side plate will no long line up with the body.
a bit ugly, so I will put back stock end plate.
thanks to you. you helped us fixed start issue. and saw your post on transient throttle, which fixed most of the stuttering issue by noon.
this beat Savington's previous record by 0.1 sec. but to be fair, there was with a chicane repavement 2 months ago, which is worth 0.25 - 0.5 second depending on who you talk to.
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