yourmom23

iTrader: (4)

Wow still getting major creep. I have ported my waste gate to the max with the secoundary flapper, and sure enough holds 7psi then when i hit around 6k it starts creepin all the way up to 14psi at redline. I have the pettit ecu which should be some what safe up there.

So you have herd of grinding down on the other side of the waste gate so it opens further i had done that but was just playin with it and it really doesnt give you much more opening, because the waste gate does not extend far enough. So i think i am going to try cutting the waste gate plunger and adding 1/32 of length to it so it will open further. To my calculations that is far as you could extend it without the flap bing cracked open. Has anyone done this??? i have never herd of it but am willing to give it a shot.

Oh also my mods are street port, and 3in turbo back with three in inlet muffler.

arghx

iTrader: (3)

search restricter pills

Prophet7000

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/wastegate-porting-observations-726267/

yourmom23

iTrader: (4)

I did do this but thats what i am saying is that your plunger does not have the ability to extend to the stage that you grind out. thats why i want to extend the rod on the plunger.

yourmom23

iTrader: (4)

They are not in, im on strait waste gate press.

Prophet7000

I don't know if it's been tried before, but you could try shortening the external arm of the wg flapper that attaches to the wg actuator. That way with the same movement of the wg actuator arm, you should get a larger angle of flapper movement.

yourmom23

iTrader: (4)

Well i think im going to try it cuz, i dont see any other way to control it without making exhaust restrictors. It just seems like no one has this much trouble with creep after porting the waste gate. I have trouble shot everything so i guess the street port put it over the edge.....

Sandro

iTrader: (1)

I am not sure if what I am going to say is completely accurate but boost creep may have to do with the inability of the boost control system (bleeding too much air from the WG actuator) to fully open the wastegate. ARGHX started and has been contributing an excellent thread on the boost control system operation https://www.rx7club.com/3rd-generation-specific-1993-2002-16/why-engine-so-damn-complicated-part-1-sequential-turbos-demystified-841821/

Data I have been logging confirm that even a "closed loop control system" like in the PFC can only reduce the duty cycle by no more than 15% from the duty cycle set in the ECU, as indicated by ARGHX. If your duty cycles are set high (which is desirable to obtain higher boost), the bleeding valve solenoid would still cycle at relatively high duty, and may not allow the wastegate to open fully.

FYI, I use the PFC to control boost creep, by pulling ignition timing to zero at high boost. A lot of banging and sputtering when it kicks in, but I can enjoy the free flowing exhaust - and resulting fast turbos spooling - until then, with no need for mechanical restrictions in the exhaust.

- Sandro

arghx

iTrader: (3)

If you were on straight wastegate pressure, you would have the nipples from the precontrol/wastegate actuators to the their respective solenoids capped. Then you would run pressure directly to each actuator with no pills. It would be the same as running internal wastegates on any other car without a boost controller.

And there is the matter of your ECU. Are you running stock ECU or Power FC?

I wouldn't take that number as gospel or anything but it's important to know that any self-correcting system has to operate pretty close to its targets in order to maintain consistent operation. That's why even highly sophisticated modern OEM boost control systems (like on Subarus) still need to have the wastegate actuator tensioned properly if the vehicle is modified. The more you study modern OEM systems the more you realize just how simple/crude most aftermarket stuff really is.

FD3S2005

iTrader: (11)

i got the brn stage 3s and bryan ports the waste gates, and i still get creep, it didnt bother me untill i got a rebuilt for a coolant seal. i got a minor tune from the builder and i was getting creep and i dont trust the tune 100% so i threw on the stock cat till i can get it tuned..., if your having so much trouble and want to fix it, restrict the exhaust just a little bit. you will lose some power but better safe than sorry.

get tuned for 14psi then if thats the max it creeps.

Sandro

iTrader: (1)

You can stop boost creep with the PFC, which you have, with no need for any restriction in the exhaust, as indicated in my previous post.

- Sandro

Sandro

iTrader: (1)

As indicated in my previous post, you could stop boost creep through the PFC, which you have, with no need for any undesirable restriction in the exhaust.

- Sandro

yourmom23

iTrader: (4)

I do have the selinoids capped so they have no influence on the boost creep, i have a single boost controler hooked up as i am runnin non seq. I am running a pettit ecu.

yourmom23

iTrader: (4)

It has nothing to do with electronics. I have my inlet connected to the waste gate plunger, that becomes fully compressed when 7 psi is made at the inlet of the turbo. It is creep there is no way around it, it just flows too much exhaust for the waste gate to bleed off in a timely manner.

Prophet7000

So weld a larger flapper on so you can port further or add some exhaust back pressure.

arghx

iTrader: (3)

I'm still not clear on your plumbing. You said you are running straight wastegate pressure and then you said you have a boost controller? In my mind, "straight wastegate pressure" would be uninterrupted pressure to one nipple on the wastegate actuator (other one capped). That eliminates boost controller plumbing/configuration issues completely.

Prophet7000

If you've got a boost controller on there (but supposedly turned all the way off), I'd pull it just to make sure it's not part of the problem. Also make sure the vac line to your wg actuator is all good.

yourmom23

iTrader: (4)

It is turned all the way down and i have tried it with a hose strait from the inlet to the waste gate. I just dont know how much more i can port it out the door is about as big as you can fit in there. I have checked my caps on the other side of the waste gate too and no leaks

Sandro

iTrader: (1)

I was just suggesting using the PFC - or any other programmable ECU - to stop boost creep by pulling the ignition timing to zero deg at above - say - 14 psi. This is what I have been doing and it works because the energy going into the compressor wheel gets drastically reduced, even if the waste gate may not be fully open (as it happens by cycling the the bleed solenoid - not your case) or otherwise insufficient to divert enough flow/energy from entering the compressor wheel (as it appears to be happening in your case)

- Sandro