The Detroit Tuned Bypass Valve is a re-worked new OEM valve that is modified by Detroit Tuned to eliminate the "Yo-Yo" in the MINI Cooper S's, the yo-yo was more prevalent for the early 2002-2004 cars but could happen in any of the years. What is the "Yo-Yo" effect? It's the opening and closing of the valve around 2500 rpm's so that it feels like your stepping on and off the gas, but you're not. So we added a stronger spring to overcome the vacuum condition that it sees so that it will not open as soon or as much. Our BPV closes at 6" of vacuum, as opposed to the factory value of 0" of vacuum. MINI tired to fix the problem in the 2005-2006 cars with a ECU tweak but it never really worked correctly for a lot of cars. This was the main reason our BPV was created, but there are a lot of benefits, read on!
The DT BPV uses a stiffer return spring, resulting in quicker boost generation, and thus quicker throttle response and transitions. Most cars see about 1psi total more boost @ redline. The butterfly assembly is also adjusted as much as possible to close fully, allowing for maximum boost. This is done by centering of the butterfly door and adjustment of the set screw that sets the openness of the butterfly. Perfect for the aggressive driver or racer. It is possible to see a very minor loss in fuel economy, but you will see a great improvement in throttle resolution and smoothness.
Full how-to instructions (below) and all necessary hardware is included. Easy to install in about an hour. No core charge so there is no need to return your old valve. This part only fits the gen 1 2002-2006/7 Cooper S with the Tritech motor.
Posted by Unknown on 12th Oct 2015
Love the power diffrence! Very impressive the diffrence it made in my car
Posted by Unknown on 11th Aug 2015
If so, this is a must have. I bought my 03 MCS about a month ago. I thought that it was a gas saving little turd. WRONG!!! I installed this Bypass Valve in about an hour, reset the ECU, and went for a drive. Holly smokes, my car hauls a$$ now. Must buy, must buy, must buy. Did I mention yet, must buy!
Posted by DaveVT189 on 19th May 2015
... in both performance (acceleration response) and intake noise tone. Installed on my '02 R53 (w/ 107k) mainly because I had a budget for mods and wanted to address certain "common problems" /before/ they cropped up. To be honest, didn't believe it would make that much of a difference - I can admit I was so wrong.
Posted by Unknown on 13th May 2015
Completely stopped the yo-yo I was having
Posted by Andrew S on 24th Apr 2015
Perfect part. Feels like a different car now, will for sure recommend to everyone
Posted by Allen on 15th Apr 2015
I recently bought an 03 Mini Cooper. I noticed that although it seemed to be running well, it just seemed to not have as much power as it did when I bought it. After reading through several forums, it looked like my bypass valve could be the culprit.
Being the handy person I am, I spent some time to remove and inspect the component and, sure enough, it was bad. The plunger didn't seem to move all the way out, meaning that the valve was always slightly bypassing the supercharger.
The forums highly rated the Detroit Tuned valve, but a few of the forum members talked about dismantling the vacuum-powered actuator and replacing the spring themselves. Again, being the tinkering type, I figured I'd give it a go.
To make a long story short, I destroyed my valve quite thoroughly and needed a replacement. I placed the order, got a shipping notification email promptly afterward, and my part was delivered right on time.
I installed the part, and my Mini feels like a different vehicle. It's more responsive and the power seems to have been restored.
I'm very pleased with the part and the service, and I'll definitely be doing more business with Detroit Tuned in the future.
Posted by Allison Wright on 11th Apr 2015
My 2006 MCS decided the throw the P1688 code and take me back home on a limp. I'm not very mechanically inclined, but the instructions on the website were incredibly easy to follow, so I must thank Detroit Tuned for that. I've only ever done oil changes on the Mini, but now I feel more confident in my repair abilities. It's been a week since I've replaced the bypass valve and so far, no limp mode! I've got her past 5k and she's running smoothly. Many thanks for the bypass valve and the other goodies :)
Posted by Ryan on 27th Feb 2015
My 2005 MCS threw the dreaded P1688 code, and research told me it's either a faulty bypass valve, or the crank pulley. I had no symptoms of a faulty crank pulley, so I decided to go with the more economical repair option. Install was very straightforward, thanks to the install instruction on DT's website. After getting everything back together, I took it for a short test drive, and had a smile on my face due to the improved throttle response. The 'yo-yo' effect is gone, and it pulls pretty good now. I'm very pleased. I highly recommend the DT bypass valve, whether you need it to replace a faulty valve, or just looking for an improved throttle response. You can't go wrong.
Posted by eric on 23rd Feb 2015
Just got installed and gives car an extra boost or pep and I gained extra 3/4mpg worth it amoung upgrade list . The stock had some light peeking from stop n bottom.
Posted by Pilero on 21st Feb 2015
Every where I look I hear only good things about Detroit tuned, had issues with yo-yo effect on acceleration, easy to order easy to install parts ...love the product and am super happy with the results love Detroit tuned bypass valve.