M35 Strange Exhaust Noise

[scotty nm35]

Mine is fine at 20, unless they are faulty. They should have a strong enough spring for stock boost levels and more.

Leaks in intake piping and exhaust are hard to find. I would recheck every clamp and nut before replacing parts, your car will run like crap with the aftermarket BOV even if it is plumbed back.

[StefanNM35]

I was looking at Turbosmart BOV's and will probably have one fitted when the turbo and dump are upgraded. Out of interest, do you know what model of Turbosmart you put on? I've been in touch with Turbosmart and they have recommended the dual port.

i found the bov model and its a Turbos Smart Type II Vee Port, i got it for $50 with the skyline R33 adapter which bolted up with no issues. i think the $50 was the only reason i got it. LoL

i must say that there is a bit of lag if you back off then hit it again. i always thought this is because the air is being vented to atmosphere and not to the intake. but i'm not 100%.......

personally, when the time comes to get another, i'd either go plumb back or dual. so i'm thinking their recommendation might be a good.

[Bis-e Bee]

i found the bov model and its a Turbos Smart Type II Vee Port, i got it for $50 with the skyline R33 adapter which bolted up with no issues. i think the $50 was the only reason i got it. LoL

i must say that there is a bit of lag if you back off then hit it again. i always thought this is because the air is being vented to atmosphere and not to the intake. but i'm not 100%.......

personally, when the time comes to get another, i'd either go plumb back or dual. so i'm thinking their recommendation might be a good.

Yeah, I'll give it a shot and see how it goes when the time is right. I don't want anything that sneezes or flutters every two seconds, the less police attention the better. They can pick on the subaru's instead and leave my stagea alone

[spoolin12]

As my brother (bbenny) said, I have the same issue.

Keen to hear your results Stephen.

Chris.

[dimi108]

Mine does this as well. Especially on full throttle if i lift off the gas pedal a bit (while on boost), it'll do a "brrOTTTTT" kind of noise. Sounds weird, and i can feel the vibration.

This is blow off valve, isn't it?

Are there any direct replacement aftermarket blow off valves for the VQ25DET? Or do i have to block the old blow off valve off and install the aftermarket one on the intercooler piping somewhere?

[Bis-e Bee]

Mine does this as well. Especially on full throttle if i lift off the gas pedal a bit (while on boost), it'll do a "brrOTTTTT" kind of noise. Sounds weird, and i can feel the vibration.

This is blow off valve, isn't it?

Are there any direct replacement aftermarket blow off valves for the VQ25DET? Or do i have to block the old blow off valve off and install the aftermarket one on the intercooler piping somewhere?

Turbosmart Nissan Dual Port (TS-0205-1026) is a direct replacement of the factory unit and can support increased boost levels (highflow) you can get away with the Kompact Plumb Back but only if you are not going to dial up the boost level.

The dual port comes in at around $460 and can be configured to be vent to air/plumb back etc. Obviously vent to air is illegal but I'm still going to give it a quick go to see what she sounds like

[iamhe77]

Mine does this as well. Especially on full throttle if i lift off the gas pedal a bit (while on boost), it'll do a "brrOTTTTT" kind of noise. Sounds weird, and i can feel the vibration.

This is blow off valve, isn't it?

Are there any direct replacement aftermarket blow off valves for the VQ25DET? Or do i have to block the old blow off valve off and install the aftermarket one on the intercooler piping somewhere?

hmm... that description actually reminds me of the sound my car used to make (same circumstances).

Got rid of it by allowing more air to the turbo (Powerduct and intake piping).

I was told it was the same sound that GTR's make when they suck their rubber pipe shut, thus not enough air getting to he turbo.

Haven't had the sound since.

Dunno about all this talk of the factory BOV problems, both Scotty and Craig are still using their stock BOV's and each have over 200awkw.

I am still using my stock BOV without issue and I have just turned 180,000kms on my car that regularly boosts to 1.2 bar.

Also, maybe look at putting a small grub screw in the little hole of your BOV.

Edited July 9, 2010 by iamhe77

[spoolin12]

Well I just blocked off my BOV and can't make the car fart anymore... I will try drive it a little more and see if its 100% the BOV.

It does make a wicked flutter sound now... haha. I know its not good but sounds cool!

[dimi108]

Thanks for the decent replies Stephen and iamhe77.

I'm going to block my blow off valve tonight and to determine if it's the bov or not.

Then i'll look into getting the Turbosmart Nissan Dualport if it ends up being the blow off valve.

Appreciate the help and useful info, boys.

By the way, where is the blow off valve located on our cars? Is it easy to get to?

Edited July 9, 2010 by dimi108

[Jetwreck]

top of the motor....pretty easy to get too......let me know what price you guy's get quoted on the TurboSmart BOV....I may/should be able to beat it especially if I am buying more than 1 at a time.....and it should be a pretty quick delivery!.

cheers

Craig

[dimi108]

Sweet. What's the go with blocking it? Can i just use tin to block it? I used tin from a can on my Chaser to block the factory blow off valve by wedging it in between the pipe and the blow off valve (almost like a gasket).

[Bis-e Bee]

top of the motor....pretty easy to get too......let me know what price you guy's get quoted on the TurboSmart BOV....I may/should be able to beat it especially if I am buying more than 1 at a time.....and it should be a pretty quick delivery!.

cheers

Craig

I'm not ready to buy mine yet unfortunately but I did get a price of $424.00 (plus $15 express post to Sydney) from Boostn Imports in Brisbane (they are a SAU trader).

[Jetwreck]

Guy's I have to say this.....only because I don't want to see you waist money on something you don't really need.....unless of cause you want it.

The standard M35 BOV is a pretty good unit.....good enough for me, Scott and a couple of others who have increased the boost not to change it. I went through the process of looking into them a while back but I just could no justify putting on for a car that already had a good OEM one. Especially since I am running under 20PSI......If I was up over 20PSI then I would definitely go down the road of replacing it.

If you want it just because you want on thats fine.....but there are a couple of other things I would be looking into first if you want more performance or noise!

Chris or Dimi is it possible for us to meet up some time over the weekend so I confirm what exactly the noise you are talking about is....there is a couple of different noises these cars make when things are failing.....I think I have pretty much heard them all.....just trying to save you a buck or at least send you in the correct direction to fixing the problem.

I live in Thornleigh but will be at Gladesville tomorrow morning if that helps.

Edited July 9, 2010 by Jetwreck

[dimi108]

Awesome. I'll send you a pm. I'll be away this weekend but i'd love if you could have a look and have a listen to the noise

It's a relief to have some help on hand.

[spoolin12]

I am more than happy to meet up. I will be away this weekend but will be around the beaches all next week.

Here is what I have found;

I blocked off the BOV with some rubber and went for a 45min drive to try and make it 'fart'. No farting at all. I get back home and return the BOV to stock - took it for another drive and it farts again.

Here is a quick iPhone recording HERE listen at 15seconds.

Guy's I have to say this.....only because I don't want to see you waist money on something you don't really need.....unless of cause you want it.

The standard M35 BOV is a pretty good unit.....good enough for me, Scott and a couple of others who have increased the boost not to change it. I went through the process of looking into them a while back but I just could no justify putting on for a car that already had a good OEM one. Especially since I am running under 20PSI......If I was up over 20PSI then I would definitely go down the road of replacing it.

If you want it just because you want on thats fine.....but there are a couple of other things I would be looking into first if you want more performance or noise!

Chris or Dimi is it possible for us to meet up some time over the weekend so I confirm what exactly the noise you are talking about is....there is a couple of different noises these cars make when things are failing.....I think I have pretty much heard them all.....just trying to save you a buck or at least send you in the correct direction to fixing the problem.

I live in Thornleigh but will be at Gladesville tomorrow morning if that helps.

[dimi108]

Feck. I can't listen at work lol

To block the factory blow off valve, can you just unplug the vacuum line to it?

[iamhe77]

I am more than happy to meet up. I will be away this weekend but will be around the beaches all next week.

Here is what I have found;

I blocked off the BOV with some rubber and went for a 45min drive to try and make it 'fart'. No farting at all. I get back home and return the BOV to stock - took it for another drive and it farts again.

Here is a quick iPhone recording HERE listen at 15seconds.

Yup, that is the exact same sound I had.

I still had it happen when I put the grub screw in the stock BOV, it was when we put the intake pipe on that the sound disappeared completely.

Check that your air filter is clean and that it is a high flowing item? Open the front of the airbox?

These should help and are a cheap solution... but like I said, my car stopped making that noise ONLY after opening up the intake pipe (I still have the stock intercooler... for now).

Edited July 9, 2010 by iamhe77

[Jetwreck]

I am more than happy to meet up. I will be away this weekend but will be around the beaches all next week.

Here is what I have found;

I blocked off the BOV with some rubber and went for a 45min drive to try and make it 'fart'. No farting at all. I get back home and return the BOV to stock - took it for another drive and it farts again.

Here is a quick iPhone recording HERE listen at 15seconds.

lol.....your farts must sound a lot different time mine....mine actually make a sound! .......anyway the pssshhhhh psssshhhh(starting at 14 seconds) does sound like a BOV problem. What mods have you done? could be a restriction in the system as well!

Edited July 9, 2010 by Jetwreck

[dimi108]

Yeah that fart sound file is exactly what mine does too.

[scotty nm35]

Its not hard to test a bov, just use compressed air to simulate the boost.

No aftermarket bov will ever work as well as the oem one, low throttle driving will suffer from shuddering and flutter. Block the bypass hole with a grub screw to see what it will be like...