Tuning My Greddy Type-S Correctly

[jthomp]

First off, my car is a 99 GST. THe type-s is installed with the adapter using the stock pipes. My questions are:

What is the technical difference between tuning the BOV to HARD or SOFT direction on top of the type-s. By tuning in to HARD or SOFT will I be able to get more of a response out of it. It seems like a little lag before it "blows off". Also, I have left the screw to where it came from out of the box. How many threads should I leave? I am planning to get a hard pipe with a Greddy flange, but for right now, I just wanna tune it right until the hard pipe gets here.

One more thing to maybe help figure this out, when sitting at a dead stop and "revving" (not to be stupid) there is no notice of a BOV. I mean when giving the car gas in neutral, it rev's like normal. Could this mean it's set to hard?????

Also, is there an upper intercooler pipe with a greddy flange that you all recommend that doesn't require any modification to the airbox? I wanna leave everything the way it is.

 

[TurBoGs-T]

I personally turned mine soft enough to where it blows off with 1psi. If you are lagging before the blow off you may have it too tight. or if it doesn't blow off at low boosts. I had mine loose and it held 15 solid and let off at low boost.

 

[Rogue_Ant]

Hmm, someone had a 'guide' to BOV tuning... I think maybe Kyle...

The basic idea is to take off the dump-tube (make sure you plug the hole).
Start the car, have someone hold it at whatever rpm has the most vacuum.
Loosen the BOV until it just starts to open. At that point tighten it 1 turn.
Put back on the dump-tube (if desired).

Your set. The pressure from the intake is what should be mainly holding the BOV closed, not the spring.



Rogue

 

[Thomas91169]

i just tightened it a few revolutions from being in the middle(how it came) to hard. then my freind came in and started to sinker with it, made it super soft, and it sounded like crap. so i tightened it and i love it where i have it(between hard and the middle)

 

[jthomp]

Ok everybody, Ive tried to tune it correctly but am having no luck. It's seems that it's harder for me to hit 12-15 pounds of boost now that it was earlier. I've tired turning it hard, soft, in the middle, but just can't seem to get it right. Ive tired to tune the screw but am having no luck. When the BOV does go "psht", right after there is a high pitched "tweet or squeek." Any ideas? Would it be easier to tune it with a hard UIP? I am planning on getting one soon, but for right now the stock pipes are gonna have to do.

 

[Generation X]

I show about three to four threads on my GReddy Type-S, and the car runs fine, and holds boost very well. I do get a little flutter, but that is the norm for the GReddy Type-S.

 

[Anomoly#5]

my god.

 

[jthomp]

my god.

Care to elaborate???

 

[Sephroth57]

and if youre revvin from a stop, your not supposed to boost anyway so your BOV wont make any noise.

 

[Wobble]

Hmm, someone had a 'guide' to BOV tuning... I think maybe Kyle...

The basic idea is to take off the dump-tube (make sure you plug the hole).
Start the car, have someone hold it at whatever rpm has the most vacuum.
Loosen the BOV until it just starts to open. At that point tighten it 1 turn.
Put back on the dump-tube (if desired).

Your set. The pressure from the intake is what should be mainly holding the BOV closed, not the spring.



Rogue

I wrote it, and yea, let the car warm up, take the dump tube off and get a flashlight so you can see the plunger, and slowly loosen the screw untill it just BARLY starts to open, then tighten it like one turn.. and thats it..

 

[Blk_99gst]

and if youre revvin from a stop, your not supposed to boost anyway so your BOV wont make any noise.

Now that's not quite true. If you are in neutral, and almost floor it from idle to 7000rpm, your blow off value will sound off when you let go at 7000rpm. It's not building a ton of boost, but it's a few pounds to have the bov release.

 

[Generation X]

Now that's not quite true. If you are in neutral, and almost floor it from idle to 7000rpm, your blow off value will sound off when you let go at 7000rpm. It's not building a ton of boost, but it's a few pounds to have the bov release.

Agreed!

 

[Blk_99gst]

I wrote it, and yea, let the car warm up, take the dump tube off and get a flashlight so you can see the plunger, and slowly loosen the screw untill it just BARLY starts to open, then tighten it like one turn.. and thats it..

As many times as I read this, I just can't believe it's true. For 1) I've never heard of anyone tuning a bov like that before. 2) You tell me that it's set to just open under vaccume at idle, that when I push 20psi through it at that setting, it will hold; I don't buy it.

I need to retune/reset my type S this weekend, so maybe I'll try you're method, but I don't know. I think you want the bov set as "hard" as possible, but still soft enough to release at low psi (0-5psi) without giving you compressor surge.

Type-S are a pain in the arse; I miss my 1gen bov. Just throw it on there, no setting, no compressor surge, held great up to 18psi or so.

 

[Rogue_Ant]

As many times as I read this, I just can't believe it's true. For 1) I've never heard of anyone tuning a bov like that before. 2) You tell me that it's set to just open under vaccume at idle, that when I push 20psi through it at that setting, it will hold; I don't buy it.

Then you don't understand how a BOV works.... The spring is not what holds the boost pressure. Intake manifold pressure is what actually holds the BOV closed. That is why when you let off the throttle, the throttle plate closes, and the pressure inside the intake manifold drops, it creats a pressure difference that can no longer hold the BOV closed.

So look again at what I said earlier, and it will make more sence.



Rogue

 

[cbellsondsm]

with my stock bov vented and crushed, i rev it up til about 5k and it pops off loud as hell

 

[Blk_99gst]

Then you don't understand how a BOV works.... The spring is not what holds the boost pressure. Intake manifold pressure is what actually holds the BOV closed. That is why when you let off the throttle, the throttle plate closes, and the pressure inside the intake manifold drops, it creats a pressure difference that can no longer hold the BOV closed.

So look again at what I said earlier, and it will make more sence.

The spring plays some part in holding boost pressure. If not, then why does it have a soft/hard adjustment. I know at first when I was tuning my type-s, I must have had it really soft, because I would get to my 19psi setting, but then start to loose boost (ie 18, 17,16,15) towards the top of the gear. The type-s was too soft and was bleeding off my boost. I tightened it up and it started to hold 19psi and not fade. (big16g turbo, not a t25 fader).

Well I guess I'll try your method of adjusting it at idle. I guess I thought you wanted to tune it so that it was as hard as possible, yet not compressor surge at low boost, 1-5psi.

 

[98spydert]

Sooooo, if you read the instructions, you are supposed to "tune" it at idle under vac. I personally had no luck so I went with RREs explanation of how to adj it. If you here the flutter sound (surge), it's too hard, if you hear a small whistle/squeek after the blow off, it's too loose. Just read their install instructions for their uicp/type bov.

To get rid of that laggy feeling, I connected that 2nd nipple angled down to the boost source on the turbo that originally went to the stock boost control solinoid. The boost source pushes the valve open internally to give it a faster response. It made the valve a little quieter but the valve acts instantly, even after tightening mutiple turns in.

 

[Blk_99gst]

Sooooo, if you read the instructions, you are supposed to "tune" it at idle under vac. I personally had no luck so...

When you say you had no luck, was it too soft or too tight? Was it bleeding off boost at higher rpm, or giving you compressor surge at low psi?

 

[98spydert]

The instructions say to adjust as soft as you can go until the valve opens at idle, then screw it back in a little and you're set. I took the damn screw all the way out and nothing happened so I couldn't really tell how soft I could go(all the way I guess). I like it better ~half way in with the second nipple hooked up to a boost sorce anyways. No bleeding off, no surge, and acts faster than it did set as soft as possible without the 2nd nipple hooked up.

 

[jthomp]

I think I'm getting better at tuning it. It still suffers from a little bit of compressor surge i think. I really don't know how to explain it, but it's an odd sound. I am gonna order a UICP soon, but I don't wanna do any damage to the turbo now. Most of the noises I hear are at a low boost presssure, at high 12-15, it sounds just like the BOV should. Maybe i'll tinker with it a little more. Maybe loosen it up just a hair. Thanks for the replies....

 

[Thomas91169]

wow seriously, its not brain surgery.

you couldve left it how it was when you got it and it shouldve worked fine. most people put it on hard if theyre running more boost. but it shouldnt need to go any more soft than how it came. unless youre running less boost.

you did hook up the vacuum line right? the one that was on youre old one goes to the TOP nipple, the other one is left alone unless you know what youre doing.

you made sure everything is tightened when you installed it?

i used lots of the Black Silicone RTV sealent between the adaptor plate and the stock hose. i used it between the gasket and the metal on both sides. maybe you got a leak?

on a stock application, youre not really doing much with that screw. youre just adjusting where the plunger sits in the shaft. too high, and it lets out air, too low and it lets out air. cabbish?

put it back in the middle, check all youre fittings and DRIVE it, not rev it. it will only build up 3-5lbs if you rev it. you want to set it to where it makes the squak at about 8lbs, and a big PSST at WOT BOOST(15lbs for me).

 

[jthomp]

I believe I have it pretty close. I'm not sure, but I belive I might here a little bit of compressor surge. The problem is, I really don't know what to listen for. I'm gonna loosen it a little more, about a quarter turn, until I hear this one noise stop.

 

[larryriverside]

can someone just tell me how much boost this sucker can hold? and what bov can hold 30 psi? thanks, justin

 

[hotT0Male]

i just got a low miles 4g63t put in my car after crankwalk (after more than 1 year of downtime!!). the guys at the shop broke my plastic stock bov, so i bought a greddy type-s. i filled it to a quarter tank and put a little more than half a bottle of outlaw octane booster, and i cant hit anything over 10psi. does the bov have anything to do with it? or do i just need a manual boos controller now that i have an aftermarket bov? thanks alot, and please spare my ignorance, im just starting to get into tuning and such. thanks!

 

[1fast97gsx]

you probably have a boost leak