Boost Spikes And Then Falls Below Preset Boost Setting
Announcements
-
Similar Content
-
-
Latest Posts
-
-
Oh, I also meant to say that it is possible to use a venting BOV and restrict its outlet down so that it does vent enough to prevent the sututu, but vents slowly enough that the AFM doesn't see all the air at once and makes it easier to avoid stalling. -
I'll go talk to my bank manager. Either that or my nearest western Sydney drug baron.
-
Driveability will be about the same with either externally venting BOV, or no BOV at all. Perhaps worse one way than the other, with me thinking that the definitely more flow going through the AFM through a venting BOV more likely to cause rich stalls than the perhaps more flow that the AFM might read on reversion. There is no such thing as "turbo damage" from not having a BOV at stock, or even quite a lot higher than stock, power levels. You need a big turbo with a lot of mass spinning hard getting a horrible slowdown from a slammed shut throttle before there is anything like the shaft loads required to damage things. Not an issue on small turbos. The ONLY 2 reasons that Nissan put a recirc valve onto the RB were: It is a bypass valve. It is open when under vacuum. When not on boost, it bypasses intake air forward around the compressor, which unloads the compressor, allowing the turbine to sping more freely, making the whole lot a bit more efficient when just puddling around. Throttle response should also be faster via the shorter, smaller diameter BOV pipe (when in NA, ie before the BOV closes and boost is building) which is nicer for driveability. Emissions. The reversion causes CO pulses. Eliminate the reversion (or at least, keep it away from the AFM) and you don't get that. The stalling/driveability aspect could have been tuned around, as shown one example of by dose above, if Nissan hadn't put a recirc valve on. Many many turbo engines before the RB had no BOV. They did not stall. See the RB30 turbo as an example. Nistune is definitely better than just stock ECU. It allows you to access and change things that are not excellent on the stock setup, and allows you to do mods like put decent injectors in, relocate the AFM, put a bigger turbo or even cams, etc, on, change to coil swith completely different swell needs, etc etc. All the things that you might need or want to do 25 years after the car was new. Aftermarket replacement ECU is obviously better again, because it gives you even more freedom from the constraints of the stock ECU. I won't be needing to go any further than Nistune though, for the new turbo in the 250ish rwkW region I'm going to, with big injectors, and most other things being stockish.
-
Lucky the prp block is supposed to be released next weekend
-
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now