Well, it’s time to replace the BPV on my mini. With the motor off (no vacuum), the actuator does not seem to have enough spring pressure to even close the valve on the way…so I’m assuming that the spring is broken on the inside of the actuator.

So….I can either over a DT bypass valve….or go with the stock mini bypass valve. Assuming that I adjust the stock valve so that it closes all the way…..just like the DT unit, is there any advantage to going with the DT unit? From what I’ve read after searching through all of the posts on the topic….the DT valve seems to make the boost build less smoothly than the stock valve. Kind of like it goes from no boost….jumping into lost of boost all of a sudden, while the stock valve with the lighter spring lets the boost come on smoother and more linear. I’ve also read that the DT BPV will get into the boost sooner, lowering your MPG a little. If both valves are adjusted to close fully…..the overall max boost at WOT should be the same with either one right?

Can I get some opinions from those of you who have went with the DT BPV, or went back with the stock unit…and why? Thanks!!

I guess I’m just trying to get as much info as possible before I make my decision on what to buy.

 

I switched to a DT bypass valve at 20,000 miles on my 06S. I have often though about going back to the OEM valve. I have to accelerate very slowly not to be in boost and it does effect gas mileage around town. I'll sell you my OEM BPV for $75 if you want it. I never experienced any Yo-Yo effect with it, I just had the MOD fever so had to try the DT.

 

Besides the lower MPG...was there anything that you liked about the DT BPV? As far as low end power, and throttle response....did it help that out?

 

It does seem to increase the low end with the boost coming on a little faster. It's harder to tell now because I have a 17% pully and Sprint Booster since installing the DT valve. Seems that I just touch the gas I'm at 8psi psi boost at 3000 RPM.

 

I personally chose to mod the oem valve. I adjusted it to close all the way, cleaned it up and did the vgs mod. I'm very happy with it, works great, and if i'm not mistaken... may even get better mpg... its certainly a lot more fun!

Be ware that getting to the bpv is much more entitled than i thought it would be... takes around 2 and a half hours the first time. Also make sure you get some 7mm bolts in case you have to take out a stud in order to get the manifold out.

 

Agree with Luseboy that if I had to do it over again, I would clean up the OEM valve and try a stronger spring. There are some threads in here on doing that.

 

I'll do some searching on here and see what I can find.....but does anyone know where to get a new spring from....and what kind I need?

If I could save some money by just replacing the spring...that would be great!

Has anyone ever went out and tried to find just a replacement spring for the stock BPV? If a weak/broken spring is such a common problem…why doesn’t anyone just sell the spring? I’ve searched the site from top to bottom and I haven’t found any info on just replacing the spring. Has anyone pulled a stock (or DT) BPV apart and gone to Ace Hardware or any other hardware store and tried to match up the spring? Sure would be cheaper than spending $100+ on a new BPV. Any info on just replacing the springs would really help me out!

 

I don't see why you'd need to change the spring... The vgs mod works wonders and only costed me about $4. If you dont know what the vgs mod is, check it out on the "how to" forum. Having a stronger spring will acctually give you the same bad mpg that you get with a DT. You should look through the vgs mod thread though, there is a ton of good information, and a lot of really good test results. The vgs mod is my favorite DIY.

 

Well...I wired the bypass valve shut just to see how much boost my weak bypass valve was actually letting by since it wasn't closing all the way.

WOW!!!.......it was like the thing instantly gained 50hp!!

I've only had the car a few weeks, and I been disappointed by the power...and even more so since it's a JCW MCS. It was sluggish, and didn't really have much power at all...and under 3000rpms it was a total dog.

With the bypass valve wired shut, it was crazy how much more power the motor has. Torque steer was trying to jerk the wheel out of my hand in 1st gear, and 2ns wasn't much better. I'm VERY happy with the power now......now my only question now is if I should go with the VGS mod and leave the bad spring in the stock BPV....or just spend the money on a DT BVP and replace it.

I do lots of highway miles to and from work.....so not loosing a bunch of MPG at cruising speeds (70mph...3000rpms) is a big concern to me. What's the best option??

 

Well, I finally got the new DT BPV installed. It was actually pretty simple....took about an hour and a half to complete the job. The car runs so much better now.....it actually has power when you get on the gas now! According to my boost gauge, I'm getting around 12psi at WOT .....I'm assuming that's about right since it's a JCW car with the 11% JCW pulley on it. It runs great now!! I was thinking about getting the 17% pulley for it, but now that it's running good...I think I'll just leave it for awhile.