Boost Creep
 

Ok so getting my car tuned and am having a little issue well like several but fixed the others. Greddy kit, rs bov, emange ultimate, and agency power full exaust. Ok the wastegate has been plumed to the turbo(Known as fix #2). I have a hallman bc hooked up but its all the way loose. Having boost creep issues. between 4000 and 5000 rpm boost creeps from 6 to almost 8 and doesnt seem to be stoping. Havent gone above 5000 rpm cause at 8 psi im maxed out on fuel with afr at 11.2. Will putting my stock midpipe on help or cure this. Thats were im at right now and retest tonight. Made 253 whp at 6 psi max rpm 4200 so far.

11.2 is not really that bad. It is a very acceptable AFR, especially at 8 PSI and 5K.
I had the same issue with one of those things. A little fix will get your creeps under control.

Depending on how it is connected you need to ensure that there is a proper bleed available.

I am not very familiar with the actuator on the greddy. Is it single or dual port?

Regardless, here is a schematic of how to hook it up, in either case:

http://lh4.google.com/vdarevsk/R8TDa...jpg?imgmax=800

In case 1 you set it up to fight agains the tention of the W.G spring (in case it is very tight, by default) and you want to run less boost than that.

In case 2, you set it to provide additional resistance by letting the air press on to the Actuator membraine in addition to the spring. Extra pressure is just bled to the atmosphere.

VERY IMPORTANT!!!
You want to insert an 1/4" copper tube of about 1.5 inch long (with a little hole drilled in it) somewhere before the hose is connected to the W.G actuator.
This will bleed any pressure from the lines, thus allowing the waistgate to snap close after it has opened and the pressure has been releived.
Make the hole as small as possible to start with, and then you can make it bigger little by little until the boost creep is completely gone. 1mm should be about right, but depending on the size of the hoses and the tension of the spring on the WG, you may wanna go smaller or bigger.


EDIT:
OOPS, forgot to draw the bleed pipe to the case 2. :)
Same as in the case 1 you need to put a bleed (copper or whatever) little tube somewhere before the hose is connected to the actuator

Hope this helps.

I always understood that a bleed would raise boost pressure cause pressure is being bled off thus the wastegate is getting less pressure and staying closed longer producing more boost. Mabe im missing something?

The wastegate is a single port on the greedy. Is the device in the drawing with the adjustment wheel the boost controller. If so can it work like in case 2 with one side to atmosphere. If so is that not essentially a bleed also? Wouldnt adding a bleed technically also be like adding a vaccum leak?

What if it went wastegate>>>bleed>>>boost controller>>>>Charge pipe<vaccum source> Would that work like your describeing?

I suspect the exaust is to free flowing not enough resistance to cause the exaust gases to go through the wastegate instead taking the path of least resistance=damm race pipe

why not get a boost controller?

Alternatively, you can upgrade the wastegate actuator. I don't like the one that comes with the greddy turbo.

A tiny boost leak actually for a PUSH type setup, (case 2)

Case 1 Introduces no leak at all up to the point where the target pressure is met.

What vacuum source? unless you are off throttle, your entire intake system is pressurised, therefore there would on be any vacum to pull the WG actuator open.

There is not much resistance after the turbo. There is always plenty of exhaust pressure in the pre turbo, when driven hard. that is why the turbo is spooling up.




What happens is, if you have a closed hose, in case 1, once the boost is high enough
it will open your waistgate, and lower the boost pressure, but the waistgate will remain open after that, because once the BC valve is shut back again, the pressure inside the hose connected to the actuator will remain, and will keep the waistgate open.


In case 2 it works the other way around. You want that waist gate to stay shut all the way until the boost target is met, and you want it to shut right back again once it goes below the boost target and the BC valve comes closed. The bleed tube, gives you a little bit more control of how much granularity in the way the air is bled by providing you with a wider tuning range in the BC itself.
Like if without it, one click on the BC wheel may approximately mean 1PSI or more, this way it may stretch that 1 PSI it across like 3-5 clicks, so you could tune it in more accurately.

How do you have your BC set up right now?

Mine was a dual port actuator, and after experimenting, I settled on having a tighter spring, and case 1 working very well, and keeping the boost exactly on the desired level.

the draw back of it is: if your BC hose accidentally pops off or gets damaged, you will have your waistgate set to max. but you can minimize that by selecting good quality hoses, and securing them on with some clamps or zip ties.

Another thing to take a note on, is depending on how it is set up cas1 or 2 the position of the boost controller Wheel will be reversed.
Meaning
Case 1 the more you open the BC, the less boost it will make as there will be more pressure from the charge pipe to the actuator.

in Case 2 it is the opposite. the tighter BC is shut, the less bleed action is going on, the more pressure is applied to keep the WG closed.

Examine your setup to make sure you don't have it mixed up, because that is what it sound like.
If I am not mistaken greddy actuator has a 6 PSI spring, and it shouldn't go past that pressure even if the boost controller is disconnected all together. (Unless it is so crappy, that it just don't wok properly)

:dunno: $$$ maybe.
Once you figure it out and hook properly, it works very well, and at a fraction of the cost.

My boost contoller is set up wastegate to boost contoller to charge pipe coming off turbo(taped the pipe with a 1/8th npt fitting). I have a dyno graph but it lets off at 5200 rpm at 12.2 afr due to boost creep. My boost controller is all the way loose its a hallman bc pro light with a ceramic ball. The stock midpipe is back on. I think its on the dyno tonight just waiting to here how it went.

so technically if it is all the way loose, you are allowing it to build max boost.
think: the air from the charge pipe presses on the waistgate actuator keeping it shut without any obstructions and in addition to the actuator spring.

shut it close all the way (opposite direction) and you'll see that the car won't build more than 5-6 PSI on the spring alone. (or just yank the hose off the actuator port to be sure)

12.2 is a bit lean, but it is not because of the creep, but because it is just lean in that area due to your tune. You need to add fuel to cover for it.
Your stock fuel system is well capable of providing adequate fuel for over 10 psi. At 8 psi, you will not run out of FS capacity.

It being all the way loose has it doing nothing to the signal. If i tighten it it will bleed off pressure causing the wastegate it to stay closed(Has a + sign and clockwise arrow; - sign counterclockwise arrow). I thought that the stock fuel system coud handle more psi but my tuner says theres no more fuel. I dont kno if hes tryed to add but he was saying he couldn't. I havent heard from him yet hopefully its done well see.

Sounds to me like you need a new shop/tuner... the stock fuel pump can flow enough fuel to support over 400 hp with upgraded injectors :lol: . The stock injectors are good for a considerable amount as well... should be able to get in the 300 range before you run out of injection volume. If you are only shooting for 6 psi there should be plenty of volume to play with. :icon_no2:

I use the BC you have, and +/- has nothing to do with it and will work in reverse depending on how it is hooked up. There is nothing more than a ball and a spring inside that thing. +/- It simply indicates the direction of rotation to tighten or loosen up. The more you turn it in the + direction, the tighter it sets the spring inside your BC. Don't believe me. Go pull the hose off the WG actuator and you'll see. It will stop making boost above 6 psi (Given that your tuner has not set the WG actuator spring too tight).

Start by looking at how your actuator is installed. to make sure it is not in too tight, loosen it all the way out, so that there is virtually no tension on it, and you can just push the waist gate open with your finger. Then give it a run, an see where the boost lands. if it is too low, (below 5-6 PSI) tighten it one full turn, and give it another try, and so on until you get the WG to function as intended on it's own (like 6PSI or so).
After that, hook your BC, and give it a try. If it spikes up again, you know it is not hooked correctly. Hook it up the way I described (example #2) and it should work.

I am trying to offer you help based on the fact that I know firsthand what I am talking about when dealing with this type of controller. You on the other hand keep on making excuses for your own setup, or (looks like not a very competent) tuner, hoping that the problem one day may just decide to away on it's own. It is a huge pain in the ass to get to that actuator on the greddy, once it has been installed on the car, but it is just something that must be done if you want your car to ever work properly. With that said, do as you wish. Good luck.

I don't know about 400WHP, on the stock pump, sounds a bit too excessive, but I had seen 9.5:1AF on my car at 10-11PSI and 6-7K RPM when it wasn't yet tuned in. There is plenty of capacity in the stock FS for what he's looking to accomplish.

That's quoted from a recent post by MM, so I'm getting it from the horse's mouth so to speak.

Thanks man dont get the wrong idea im thankful for your suggestions. The cars tuned for now and drives great. Im going to post the dyno graphs as soon as I can.

I love my supercharger..... :evil_laug