View Single Post
Thierry25 Thierry25 is offline
Registered User
Join Date: Feb 2009
Location: FRANCE (Besançon)
Posts: 310
Hi Dave

Thank you very much for your confirmation and your valuable advice. At present time I will apply between 1.0 and 1.25 mm for the setting. ( It seems it is always a compromise .....and compromise always need a choice).

As to the Digital WUR, I still have no news from this is a a pîty because my car is at the workshop now and it woud be the right time to install this device while the engine will be out of the car very soon. At least they could tell me how long I am supposed to wait ... Of course I will keep you and the community informed of the result/ opinion if I install this device. In order to make the right tuning, I just ordered a complete innovate system and I will be able to record the AFR, EGT , MAP, RPM ....

By the way, I just get one idea of improvment which I would like to submit to you and to the community here. In fact this idea ( probably not new) would concern a "variable" boost pressure control and come from simple observation. The torque and power is always very high in the 4000 to 5500 range. Then after 5500 rpm the torque and the power drop. This is certainly due to the cam setting, lower air and fuel filling (maybe ignition timing either). However, I am wondering what would occur if I could increase the boost pressure between 5500 and 7000 rpm. ( of course the AFR would be adjusted accordingly by digigital wur). The wastegate keep the pressure at 0.95 bar ( at least it is supposed to do it) from 4000 to high RPM. However there is some extra potential energy here since the wastegate limit the MAP pressure and lead the extra air from the turbo directly to the atmosphere. As you know the boost pressure can be increased if the wastegate upper vent ( on the top cover ) is closed or restricted. So it is possible to control the wastegate behavior by acting to this vent. My idea would be to install an elctrical valve ( driven by an RMP switch) which could link (simple hose) the intercooler pressure to the vent of the wastegate. From idle to 5500 the valve would simply lead the wastegate vent to the atmosphere ( so there is no addition boost pressure and the wastegate have a standard behavior). Beyound 5500 rpm the switch would acting the valve which would link the (roughly equal to MAP) pressure (which can be adjusted through a knobs) from the intercooler to the vent of wastegate. Thus the boost pressure would be increased accordingly. RPM switch would be very easy to do for me since I can program an alarm with the MAP and RPM sensor that I will install on my car and use this "alarm" to drive the electrical valve.

Ok maybe this a stupid idea but if you or someone here has some comment and experience about something equal or similar ?

Dear Mark, I don't have any possibilty of such kind near my city . If so I would have contact them already .
965 C2T / 1991 3.3 TURBO

Last edited by Thierry25; 02-15-2009 at 02:11 AM..
Old 02-15-2009, 02:08 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #8 (permalink)