BOV BPV reviews

[skatethesea]

I am looking into my next purchase. Which will be a BOV/BPV. Now I know there are a ton of em out there. And you can get an adapter plate for all of them. I know how they work and what they do. But my question is more towards, which one will allow me to eventually function best at 23-25psi while still being fine for stock PSI. As of now I am relatively stock. I am sick and tired of not maintaining boost past 5k rpm. And the amount of lag for a turbo the size of my left nut if uncalled for. So I would like to upgrade the clamping load on my BOV at WOT and open-close time during shifting. I dont care about the psssh, wooosh, pffyyiishh sounds. I just want a better engine. So if you have an aftermarket BOV/BPV roger up and lets here some experience.

Thanks
-Skate

 

[MSMS3]

A bpv or bov WILL NOT allow you to maintain boost past 5,500 rpm on stock tune. The ECU starts closing the throttle plate to save the turbocharger due to overheating of the turbo. It's not your BPV that is causing this. An aftermarket tune is needed to maintain boost at higher rpm. In fact, with my intake and catless dp/rp on stock tune, I was spiking to 21-22 psi with the stock bpv. And even after my tune, with the spikes gone I have a steady 18-19 psi target with slow taper to 17 at 6,000 rpm, the stock bpv positively does not leak.

You are never going to be able to run more than 19-20 psi under load on the stock turbo at rpm above 5,500-5,800 rpm. The turbo simply gets driven into ineffeciency and starts creating excessive heat rather than more power. Exhaust gas temperatures climb to unsafe levels.

With respect, if you want another BPV or BOV, then you need to look for some other reason to justify it. Any BPV can leak, including the stock one. It seems less likely to leak, IMHO, than the aftermarket ones and certainly gets the job done efficiently at boost levels at or above the maximum safe levels for the K04 turbo. I can't make my stock one leak.

In fact, you'll frequently hit load cut at around 17.5 psi turbo boost on the stock tune. Unless you have an aftermarket tune that raises the load limits, AND have a big turbo that can handle 20+ psi boost levels efficiently, there is no power to be gained from a BPV change.

 

[supersuckers]

I forget which issue, but GRM had an article where they claim to have opened up top end power by using a CAI and the COBB AP.
http://grassrootsmotorsports.com/project-cars/2008-mazda-mazdaspeed3/five-minute-workout/
I do not beleive replacing the stock BPV will will have the desired effect you are seeking.
Good luck!

 

[skatethesea]

MSMS3.... Thank you for the input. That is very good information. I do plan on going with a 3071 turbo by the fall. And I will of course be incorporating the COBB AP and all associated parts for such a build. I misunderstood the issue with the tapering of boost at high RPM. It is, however, to see that it is actually the stock turbo that lacks in the ability to make consistent power to redline. That pretty much sucks. I guess I was just dreaming of an easy way to non stop boost.

And thanks to you also SUPERSUCKERS.

Cheers

 

[MSMS3]

Although I have the more modest (and safe) HT tune for my purposes, if you are going to go big turbo later, it would make sense for you to go ahead and get the AP and start experimenting with maps for your mods and get used to the learning curve for the ATR self-programming. At a minimum it will release the throttle restrictions you have now on 0-60 mph and the proper OTS map (with help from Cobb and users here familiar with its likes and dislikes with various mods) you ought to be able to lift those load limits some and get some more usable power above 5,800 rpm without getting into trouble. Once you are familiar with the tuner and the ATR programming, you'll be ready to make the jump to BT or ready to get a custom tune with it from a reputable tuner. Good luck. My guess is that your stock BPV will still work great. Most big turbo applications actually don't have to go above 20 psi to make as much or more power than your block's internals can handle anyway.

 

[skallen]

^^^ Man I love this guy!!!! MSMS3, you really know your s***! I never get tired of reading your posts. Very informative and extremely helpful. Your opinions and advice changed my mind on my want of a Cobb AP (not to mention the destruction of several others' engines). For that, I thank you for filling us, less knowledgeable people, in. I appreciate it!!!