Swapped in stock DV now reads KR
 

mods: PG SRI, TXS BPV, AP - stage 1+sf 91 v1.04

I wanted to see if the stock dv performed any better/worse than my txs bpv. Right off the bat idle was reading -10.6vac vs the txs -12.4vac. My LFTF went from -12ish cruising to -16 wtf? As well I saw KR upwards of 3.5 on the hwy and the car generally felt rough and didnt perform as well...

does this sound normal? Im switching it back asap....I didn't think it would be so blatant.

Get a used Forge BPV.

the TXS bpv has been great so I dont really have any reason to replace it. I was more shocked to see how bad the car ran when i swapped the stocker back in...

By DV I am assuming you are talking about the stock BPV? If so, something is not right. Your idle vac should be much lower with either valve - like -20 to -22, or at least mine is.

Also, if you are monitoring with the AP, you probably need to reset your ECU first, maybe you did, and even then, instantaneous changes are not likely to be accurate. How long have you been running the stock valve since you put it back?

Also temp, humidity, altitude all make a difference on how your car performs. If you were monitoring long enough to get valid long term fuel trim data, you may have been monitoring each valve under different atmospheric conditions. Hard to make comparisons based on info you supplied.

How is boost holding in comparison under conditions?

I'm wondering if you are only getting negative 10-12 vacuum at idle maybe you have a vacuum/boost leak somewhere in the system. Just a thought.

Been through this before.
AP reads psi 10-11
Dashhawk reads inches of something.... water.... Hg...... I dunno, but at the end of the day, different units, different number.
Same really.

I didnt reset the ECU. That probably had something to do with it. Now after 50+km the car feels much better. Im still planning on switching back to the txs bpv. Because of the winter here I havent seen boost hit anywhere near the target for this map on the txs....the main reason why I swapped it out...now with the stocker I saw 16.5psi today but it was milder in comparison to when I had the txs on.

Thanks for the help....Im still learning all this as I go. The STFT and LFTF are confusing because there are so many different answers to what they are...

Ignoring STFT makes life a lot simpler.

Yeah, I run a manual vacuum/boost gauge. That is registering in inches of mercury. Different units. Thanks.