Jump to content
SAU Community

Recommended Posts

Hi um i have been wondering and debating with my friends for quite a while, what makes the BOV's (or the majority of) on VL turbo's sound so bad? Like normally i dont mind the tshhhhhhh sound but the VL turbo's go tsh tsh tsh tsh tsh like in fast succesion at a high pitch and its hilarious. I have noticed HKS sequential BOV's which i assume let the air off out of 2 openings and thought perhaps this could be the cause of queerness. Also i was wondering if it could be that the BOV is like loose or far to small or something? Like its slapping open then coming back down on itself and being slapped open again by the air rushing out. Could it be like absurd amounts of compressor wheel surge or something?

I know thats not really skyline related but well i dont know a huge amount about turbo'd cars and have been laughing at VL's for like 5 years trying to figure out why they (or the vast majority of) them sound so gay. ( and they got like r31 engines in em right?)

Link to comment
https://www.sau.com.au/forums/topic/112733-hilarious-vl-turbo-bov-sound/
Share on other sites

That noise you are reffering to is called compressor surge. It personal choice whether you like it or not but the reason why it makes that noise becasue as you take your foot off the throtle their is no BOV for the air coming from the turbo to ecscape so it goes back out through the turbo making that tsh tsh tsh tsh noise.

No blow off valve & no intercooler

They do have an intercooler, finding a decent picture of a stock RB30ET engine bay is the difficult part

nissan_motor_gerry.jpg

See right before the throttle body, that is a factory VL Turbo intercooler.

It can still make that sound with that crossover pipe because it doesnt have a BOV(im pretty sure) that tiny cooler thing isnt really going to effect the compressor surge. If its taken you years to work out what that noise is well you havnt been round very long cause theres normally a thread about it weekly

It can still make that sound with that crossover pipe because it doesnt have a BOV(im pretty sure) that tiny cooler thing isnt really going to effect the compressor surge. If its taken you years to work out what that noise is well you havnt been round very long cause theres normally a thread about it weekly

what

ahh but my car doesnt have a bov and doesnt make the queer noise. Is it because of a larger turbo size? Like more air banking up and rushing back into the turbine when ur intake(?!?) closes makes the noise right, so a bigger turbo would produce more of that and make more of a noise out of it?

They do have an intercooler, finding a decent picture of a stock RB30ET engine bay is the difficult part

nissan_motor_gerry.jpg

See right before the throttle body, that is a factory VL Turbo intercooler.

lol, that's not much of an intercooler :)

r32 gts-turbo- when i got a new motor fitted in my skyline rb25/30, and at that time i didnt have a bov for it (now it does) it made the exact noise but yeh i didnt mind it too much, but mine flutters at low psi then has the usual bov whoosh at higher boost levels

ben...

Guest
This topic is now closed to further replies.


  • Similar Content

  • Latest Posts

    • My thinking is that if the O2 sensor is shot then your entire above described experience is pure placebo.
    • Here is the mess that I made. That filler there was successful in filling dents in that area. But in the middle area. I can feel dents. And I've gone ocer it multiple times with filler. And the filler is no longer there because i accidently sanded it away. I've chased my tail on this job but this is something else lol. So I'm gonna attempt filler one more time and if it doesn't work I'll just high fill primer the door and see where the issues are because guidecoat is of no use atm.
    • Ok, so I think I sort of figured out where I went wrong. So I definitely overthinked it, and I over sanded, which is probably a large part of the problem. to fix it, I ended up tapping some spots that were likely to be high, made them low, filled them in, and I tackled small sections at a time, and it feels a lot better.    I think what confused me as well is you have the bare metal, and some spots darker and some are lighter, and when I run my finger across it, it' would feel like it's a low spot, but I think it's just a transition in different texture from metal to body filler.    When your finger's sliding on the body filler, and crosses over to the bare metal, going back and forth, it feels like it's a low spot. So I kept putting filler there and sanding, but I think it was just a transition in texture, nothing to do with the low or high spot. But the panel's feels a lot better, and I'm just going to end up priming it, and then I'll block it after with guide coat.   Ended up wasting just about all of my filler on this damn door lol  
    • -10 is plenty for running to an oil cooler. When you look at oil feeds, like power steering feeds, they're much smaller, and then just a larger hose size to move volume in less pressure. No need for -12. Even on the race cars, like Duncans, and endurance cars, most of them are all running -10 and everything works perfectly fine, temps are under control, and there's no restrictions.
    • Update: O2 sensor in my downpipe turned out to be faulty when I plugged in to the Haltech software. Was getting a "open circuit" warning. Tons of carbon buildup on it, probably from when I was running rich for a while before getting it corrected. Replaced with new unit and test drove again. The shuffle still happens, albeit far less now. I am not able to replicate it as reliably and it no longer happens at the same RPM levels as before. The only time I was able to hear it was in 5th going uphill and another time in 5th where there was no noticeable incline but applying more throttle first sped it up and then cleared it. Then once in 4th when I slightly lifted the throttle going over a bump but cleared right after. My understanding is that with the O2 sensor out, the ECU relies entirely on the MAP tune and isn't able to make its small adjustments based on the sensors reading. All in all, a big improvement, though not the silver bullet. Will try validating the actuators are set up correctly, and potentially setting up shop time to tune the boost controller on closed loop rather than the open loop it is set to now. Think if it's set up on closed loop to take the O2 reading, that should deal with these last bits. Will try to update again as I go. 
×
×
  • Create New...