Well i was having huge spiking problems before. So i changed my shitty drag manifold out and now i have a inline pro mani. Everythign seemed to be ok on the street. only boosting to 10psi to make sure it wasnt spiking anymore

Well i went back to the dyno to get tuned and basically its not spiking anymore it is regulating the boost now fine. No spikes
BUT
it isnt holding the boost right its up down up down up down
going vrom pshh vrrom pssh. (but not spiking over the set psi on the boost controller)

I took my WG apart
and baam i find this



I think this is my problem the diaphram is not staying seated on the bottom of the wg its moving up with the valve.

how can i fix this now? Anyone had this problem before?
Thanks
Justin



Modified by crazyimport at 6:48 AM 8/31/2005

 

Only help from me would be to just talk to Tial directly instead of listening to other peoples advice - it seems to work better for me when I have problems with things that are not sposed to break.

http://www.tialsport.com/

 

thanks man.
This year has just been a freaking headache i havent even ran the car yet at the track and its SEPTEMBER


P.s
love your car

 

thanks - yah believe me I went through my share of problems... just stick with it and dont take any shortcuts

 

anyone have any suggestions i what i can do to hold it down?
do you think this is the root of my problem ?

 

is that diaphram supposed to move up and down with the valve???

 

What boost controller are u running? If you disconnect the boost controller, does it still do it? It sounds like a problem in the boost controller setting somewhere.

 

boost controller is holding the boost fine at the desired psi. not goign above it.

Blitz SBC i-D is what im running

 

Doesn't look like anything is wrong from the picture. The top that you removed actually sandwich's the diaphram in the grove of the bottom. Just stick the diaphram back in the groove and bolt the top back down, then blow in the side port and see if it holds pressure. If the diaphram has a tear then you could have a problem, but the problem would be overboosting. There was a spring in there also right?

 

ah ok.. so the top peice will hold that bottom diaphragm peice into place so it wont move up

i think i might of figured out what the problem was
The valve was not sittign properly (that just started when i got to the dyno)
I think the little screws came lose a bit and the valve moved up a bit.
Now boost will not build up correctly when there is not a perfect seal right?
This is probably why i was losing boost and then gaining it back at higher rpms.

What do you think ?

 

You have a set psi on teh boost controller and you also have a warning on it. Try turning the warning up, you also have a boost correction on there i believe where it'll try to correct overboost from your warning. I definately think it's in the boost controller. Had this problem before tuning one of my buddies car with ths sbc-id Go back and check the settings, particularly the warning. Paul

 

thanks... its set at 15psi and the gain is set at 90.

 

Yes, if the set screws come lose and the valve doesn't seat you would have a problem building boost. The end of the valve actually has a grove that the 3 set screws go into.

 

yup it has a grove that it goes into. i think they just came lose.. and the valve moved up not making a complete seal because it was leaking at idle.
Now there is a screw on the nut. What is this for ?

 

from pictures your watstegate looks fine.. tears in diaphragm will cause overboost, same goes for sligthly loose vacuum connections to wastegate. does your boost controller has overboost feature? it might be that warning psi is set at 10psi, when it reaches that it pulls back.. just a guess.

 

Yea I say it looks fine.
It should seat in a little lip. And then when the spring and top hat go over it that should hold it down from fluttering.
Maybe spring pressure is weak? Boost controller probs?
Try running without the boost controller hooked up at all.

 

is that clubsi i see in the background. lol

 

excuse me if im wrong.....

but shouldnt that diaphram have a lip on it, that gets bolted between the 2 halves?????

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LiTtOGPiMp &raquo;</TD></TR><TR><TD CLASS="quote">is that clubsi i see in the background. lol </TD></TR></TABLE>

lol yes

and yes it has a lip it gets clamped by the top peice.
i made a fix. i put in a small washer in the top half where the valve goes into.
So it cant move up at all. I put it all back together and bam works fine

 

see but im still having the same problem as before...



this was a 4th gear pull see how its not staying constant at 10psi.. its going up down up down up down.

 

you mentioned before that your gain was set at 90. Change that. Set it at 50 or lower. that little spike you have in the beginning of boost where it goes to 11 or 12 psi for a sec, is caused by the gain being too high... This could also cause the inconsistincies that you are having while in boost.. Hope that helps...


(By the way, I have an SBC-id too, so I know these things )

 

sweet man thanks ill try it out. what other settings do you have setup on it?
im using tial 38mm
i also heard that with the tial wg u should have it set with the internal wg not external?

 

mine is set at zero gain, maybe thats the problem with your settings, the gain makes it spike in beginning and then go back to set level.