UPDATED WITH LATEST DETAILS!:

Turns out i have cuts/holes in diaphram..

My setup ran perfectly for 1 year/15k miles.. never overboosted or spiked.. was always steady until recent problems. i replaced vacuum lines even wastegate spring.. it spikes regardless if its boost controller or no boost controller. the only thing left to replace is wastegate itself..


basically it spikes for a second or 2 and then goes back to the level it supposed to be


Modified by vtec.dc2 at 10:36 AM 8/21/2004


Modified by vtec.dc2 at 9:55 PM 8/27/2004

 

What color spring was it?

 

What type of Tial is it? You may want to check the diaphram to see if there are any pin holes in it.

 

when power is cutting in/out, boost level seems to stay the same, it gets louder while its cutting out.

i'll take it apart again, pull diaphram and have a closer look.

 

spring was yellow..

 

How old is it? what boost levels are you running? You say the boost levels stays constant but power comes in and out? Explain more.

 

We have actually had a 38mm gate do something similar to what you are describing. When removed you could see that the valve was not fully seating, as if it was hanging up. We contacted Tial and instead of opening the gate ourself they wanted to check it out. A few days later we received it back, problem solved. IIRC something about an upper spring seat or something along those lines had broken.

Either way for Tial on that one

HTH

-Bill

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 30psiCiv &raquo;</TD></TR><TR><TD CLASS="quote">How old is it? what boost levels are you running? You say the boost levels stays constant but power comes in and out? Explain more.</TD></TR></TABLE>

its been a year and 16K miles, lets say previously it would go to .25 bar, now it will go to .25 bar if i'm running in same gear and just punch throttle, if i downshift it will go to .45 bar.. while i downshift, it will stay at .45bar but something sounds like its cutting in/out.. maybe its wastegate closing/opening.. i can't quite tell.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by AutoLab &raquo;</TD></TR><TR><TD CLASS="quote">We have actually had a 38mm gate do something similar to what you are describing. When removed you could see that the valve was not fully seating, as if it was hanging up. We contacted Tial and instead of opening the gate ourself they wanted to check it out. A few days later we received it back, problem solved. IIRC something about an upper spring seat or something along those lines had broken.

Either way for Tial on that one

HTH

-Bill</TD></TR></TABLE>

was it doing it since day one or one day it started out of nowhere.. in my case, it ran fine for 15K miles and one day out of nowhere it started

 

afternoon bump

 

bump

 

Did you mess with a boost controller? The AVCR will make it seem like it's cutting in and out...as if it was an oscillating wave. That's the way it works trying to control the spring. If you just leave the spring do the work, it will give you a linear boost increase up to the spring pressure so you only make full boost at your highest rpm. The AVCR (or other controllers) can make it so that you have full boost as early as possible and then keep a straight line of boost until redline.

 

no.. this is happening with or without boost controller.. i changed nothing at all and one day it just started overboosting for no reason.. i'll try to look inside wastegate diaphram.. if its tial wastegate i'm def. not happy with it failing after 15K miles. but if anyone has any other ideas.. let me know

 

I had a problem when I went from my .6 bar to a .5 bar TiAL WG spring. I had the dual stage boost controller set at WG pressure for the low setting and 11psi for the high setting. When I went to the .5bar spring (blue), it started to boost creep/spike at a full throttle and boost...to the point of hitting my boost cut set via Hondata (~12.5psi). So basically, I was overboosting by 1.5psi. When I returned the .6bar spring (green), the spiking went away completely. The TiAL WG regulated the boost perfectly (even seen through datalogging). Not sure if it is a similar problem, but hope you figure it out.

-Mark

 

no.. its not spring related in my case

 

oh well. good luck.

 

turns out it has to be the wastegate, i've done replacing everything else, basically it spikes for a second or 2 and then goes back to the level it supposed to be

 

Had a friend lose the seat out of a 38mm TiAL. Wierdest thing ever, the sprung valve assy had nothing to seat on.

 

i'll try taking it apart and see if everything is there or anything is loose.

would turbosmart wastegate fit onto tial wastegate flange, thats if i need to get a replacement.

 

My buddy had a similar problem on his 35 MM wastegate...it ended being that his spring has just lost the tension it once had...his fix tho was that he repalced the spring and all was fine...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by vtec.dc2 &raquo;</TD></TR><TR><TD CLASS="quote">i'll try taking it apart and see if everything is there or anything is loose.

would turbosmart wastegate fit onto tial wastegate flange, thats if i need to get a replacement.</TD></TR></TABLE>

Yes the Turbosmart Ultragate will fit the tial flange.

 

Turns out there are holes/cuts inside diaphram.. can that be the culprit??


Modified by vtec.dc2 at 10:29 PM 8/27/2004