choking when reving between 3000 to 7000

[Drift King]

I'm having alot of problem with my car choking, this only happens if I adjust my bov from hard to soft and any time that I rev my engine from 1000 to 3000 its seems ok but when I rev it from 3000 to 7000 rpm and after letting the rpm drop back down to 1000 it feels that my car is dieing and choking. However if I let my bov at hard it gives no problem so I really need to figure out how to control it, the reason is that I want a hissing sound from my bov that's why I'm experiencing these problems any suggestion would really help me, thanks!

 

[turboglenn]

It's probably pulling in too much unmetered air, or the AFR's are incorrectly set at those operating areas. The first problem will cause the second, so check your BOV routing first. If it is pulling unmetered air that's what's making the AFR's be out of whack unless you've changed the tune in that area. The softer you set the BOV the more chance it has of being open and pulling in unmetered air too, so keep that in mind. All of this mainly applies if you're venting to the atmosphere instead of recirculating like it does from the factory. If you've changed management it could just be in the tune, but i doubt that's what it is. I'm voting unmetered air as the culprit.

The only reason i can think that it would matter what RPM you revved to is that the higher you rev the more vacuum you're going to pull when you let off the gas. This will make the BOV open more than if you barely gave it any gas and it didn't pull a lot of vacuum to open the BOV up when you let off the gas. but when you've got the BOV tight/hard whatever, it's going to stay shut even with more vacuum depending on how hard it's set it might not open on vacuum alone and could need boost to be pushing on it from the inside to open. This would also be why you hear less sounds from it when it's tight. Hope that isn't too repetitive, I'm not feeling too well for some reason and my mind is drifting.

 

[absolute_DSM]

Let me guess, youre not recirculating your bypass valve and youre not using a GM MAF with a MAF translator?

reason is that I want a hissing sound from my bov

Glenn answered your problem in technical terms. But basically, recirculate your bypass valve!! Unless youre running a post valve setup like a GM MAF + translator, YOU ARE GOING TO HAVE PROBLEMS.

 

[Drift King]

Frist of all what does "GM" stand for and where can i find a GM maf and Maf Translater from. I check with autozone, checker, pepboys and nappa and they have no clue what I'm looking for. If you could clearify that up for me would be great so i can fix this problem..

 

[absolute_DSM]

Ok, you should easily search for this.

GM = General Motors. As in Chevys, Buicks, Pontiacs, GMCs, Saturns, Hummers, Saabs, and Cadillacs. The "GM MAF" is a MAF from a GM car like the Impala. I really doubt you can get a GM MAF at a local store like that. If someone came in asking for a GM MAF and MAF Translator, I would have to hold back a laugh.

eBayMotors is your best friend. Search for GM MAF and MAFT.

Yow know what would work a lot better? RECIRCULATE YOUR BYPASS VALVE. Please, do not do any modification to a car for a sound. Thats just ridiculous.