I intend to turf them when the engine goes back in as I much prefer a bit flutter however it seems like most Z32 builds I see retain them or have upgraded aftermarket units. I know the science behind having them but as this will be a street car I don't care about the miniscule slowing of the turbines between gears. Has anyone else deleted theirs completely and is there anything I should be aware of in the process?
If you delete the stock recirc valves and don't put BOVs in their place, are you just going to blank them off? When you close the throttle the air will go back out through the turbos making the car dose like a mofo. Between gears is nothing, what if you suddenly get off the throttle at high load?
I removed mine once upon a time to check if they were leaking. No noticeable difference. Concern would be around what Mike says tho.
Mine (stock) must have seized or have got some heavy springs inside them as the dose is insanely loud off throttle anywhere under 4500rpm, over it just makes the normal psshhht noise.
Not much to it, just make sure anything you don't re-attach gets blanked off properly and make sure all your intercooler pipes are nice and tight as they'll see pressure spikes when you snap the tb's closed.
I find it strange that you mentioned (in another post) that you did not like the sound of the oem recirc valves. Compressor surges (or "dosing"), which is what will happen if you do not have a mechanism to vent air, will be louder and more obtrusive.
We're not talking about 80's era BMW F1 racer running 60+psi here, I have not ever seen a turbo fail because of compressor surge in a street application with my own cars or others. Even my 2JZ E30 which regularly cops a beating on the track at 20psi or so I've not had a surge related issue or turbo failure in the last 3-4 years and it gets driven like I stole it every time I'm in it. What exactly is so strange about that? I thought I explained fairly succinctly that I detest the whoosh of stock or aftermarket valves yet I prefer the flutter noise (as opposed to nothing at all). My question was posed to find out if there is anything VG30 specific I need to be aware of while removing them, (any hidden vacumn lines or ports/sensors, etc) not asking for public opinion.
My apologies, I was referring to this post http://www.aus300zx.com/forum/showthread.php?p=1449466#post1449466 in which you described a "pathological hatred for blow off valve noise", so it seemed odd that you would want to make the (relatively) quiet oem ventilation system louder by inducing compressor surge. You can create a similar effect by pre loading an aftermarket BOV so that you have some flutter at low rpm/boost while still flowing freely at high rpm/boost (ie no risk of damage to turbo) but I suppose that depends on your goals and budget. Re Z related; aside from capping the ports where you have removed the valves you will also need to cap the 6mm vacuum tube on the balance tube (drivers side) and another on the side of the plenum (passenger side). These are the pressure reference sources for your recirc valves (ie reference pressure to the top of the diaphragm) so associated vacuum hoses can also be removed. General considerations re compressor surged are nearly summarised by the manufacturer of your turbos here https://www.turbobygarrett.com/turbobygarrett/compressor_surge One of the pitfalls of posting on a public forum I'm afraid. As long as opinions and information are politely expressed and relevant to the topic then this is where they belong. Keep in mind that while your question may have been answered, other members reference threads (particularly in the technical section) for information.
Plumb the stock recirc valves vacuum lead between tbs and turbo, closer to the turbo. this will keep the stocks closed and sound "hectic" But yeah easiest way to get it done.
Thanks for all the info gents. I assumed it would be the same as any 80/90's era Nissan and fairly simple but the Z32 being so much tech stuffed into one spot it's best to confirm before undertaking.
