I have my IX BOV crushed ever-so-slightly and did a direct back-to-back with a GFB (go fast bits) BOV, the results were impressive. With identical WGDC values across the board, the car picked up about 3psi through the midrange, but once it fell below 29psi, power was identical. I then brought WGDC values down a smidge so the boost plot was identical, and power remained about 5whp through the powerband area where boost was 29psi+. Once it was below that, power was identical.

Attachment 339428

I'll be crushing my IX BOV a bit more and leaving it as-is. I don't plan on running more than about 31psi anyways. At this level or higher, I would expect an aftermarket BOV to start to show some advantage...GST has shown that at 32psi and 450whp+ on his dyno, a Synaptic Syncronic BOV will yield up to 20whp gains, but only with some timing tweaks.


Not that its really important, but full mod list is here:
https://www.evolutionm.net/forums/ev...yno-chart.html

So, which of the two DV's gave you 5 WHP more in the midrange? Was it the GFB?

Is your car setup with ECU controlled boost? Also, what turbo, WGA and cams are you running currently?

The GFB, but like I said, I feel as though if I crush the IX BOV a bit more (it is *BARELY* crushed right now) it will be right there. Furthermore, this is *NOT PEAK* whp gains, only in the sections shown above. Sorry for the caps, but I want to emphasize this point so it is very very clear.

ecu controlled boost, but with error correction turned off for this test. My mod list is elsewhere, not really relivant to this test. Kelford272's, OEM WGA on CBRD BBK.

Sorry instead of being a dink, I'll include the actual mod list per rules of the forum. Added to first post.

Yea I saw 20whp/20wtq gains in the meat of the midrange from crushing the IX bov on a 400/400 Evo 9 stock turbo E85, 30psi peak.

I gained about 25 whp / 15 wtq on my personal car from crushing the IX bov. I crushed mine alot however and it flutters like a SOB on medium grades while throttle holding. It gets worse with altitude and lower temps as well.

- Bryan

Great test, interesting results. I might have to consider crushing mine. I have been contemplating getting the synapse too which i assume will give me the same results while avoiding the flutter issues part throttle that bryan mentioned.

Thanks for the comments Bryan!

I have yet to see/hear proof positive that the synapse would actually eliminate the flutter issues. It certainly would make equal, if not better power, that BOV is very very nice.

If I can get my hands on one to test, I'll try out the synapse and maybe a APS twin-vent at some point. If it fixed the flutter on my car, it would fix it on any car...mine has been the worst. Speed density fixed that though

are you still recircing with the SD?

Yup, I live in MN and an aweful lot of crud goes everywhere when the weather gets bad. Its nice to have all ports closed up, no chance of junk getting in the engine or gunking up the valve.

I totally agree. It is apparently better for transient boost response too.

Why are people still crushing BOVs? Properly modding by eliminating the fast release port will allow the valve to hold more boost than crushing, and will allow greater opening of the valve since you're not shortening the spring height.

http://www.thedodgegarage.com/turbo_bov_mod.html

^ It doesnt drive like stock though when you do that mod.

You should test a tial.!

and my stock bov was still leaking i tested i made my own boost leak tester for bov's at 26 psi it was opening still after all that crushing