john banks

Glad you sorted it. The only reason for suggesting adjustable was that a 0.2mm change is massive for this. A valve (even temporarily) would allow you to see what boost to run.

Cosie Convert's 95 RA (non STi) managed 12.8 1/4 mile times with a terminal speed over 111mph today at Crail on a new strip which is not so grippy yet! This is running 19 PSI on std ECU, but he has EGT, intercooler temp, Knocklink, as well as intercooler water spray and water/methanol injection. But all on the standard ECU/turbo/intercooler shows it can be done safely.

paulwadams_my99

well i took just about everything off in terms of tubes and cleaned everything and reset ecu. It now seems o.k. as i haven't been able to reproduce it. I get about 18psi peak and 16psi after it settles. This is probably 17psi i presume? I have it decatted now. I cant check knock as i don't have a knocklink. Worrying thought based on your experience Julian, what fuel do you use just out of interest? I have almost the exact same setup as John now, except for the dawes. I think that i cut my tubes too small on the dawes. Do you think, anyone, that this could account for why I was having so much boost at the dawes being almost fully extended?

I must say that the tubes connected to the solenoid looked a littly oily to me and i dont think that crack at the t piece helped.

So afr coming soon, and then i'll fit the dawes again with slightly longer tubes. I think i need to get knock checked, wheres the best place to get the knocklink scoobmania?

Glad you sorted your problem Julian. Do you think the restrictor had been changed or is that the standard size? I looked at mine and i didn't fancy trying to squeeze it out and back in again, looked like it might be tricky.

Another thing. This first happened to me on a long drive and it did once to P Croney on the track. I notice that the t piece is right under the oil pipe to the turbo. That gets bloody hot, I know cos i have blisters from trying to play with the tubes after a drive. I wondered if trhe heat can cause the pipes to get soft and perhaps expand/soften in some way at the connectors and maybe leak or certainly exagerate a crack?

Cheers
Paul.

john banks

The PPP will try to home in on about 16-16.5 PSI. A peak of 18 might upset it a bit and it will undershoot before stabilising. This is the problem I had with PPP and a DP. Best get your Dawes on!

paulwadams_my99

John,

good stuff. It seems to be ok now not undershooting since i cleaned everything. I will but the dawes back on as soon as i get the afr, but i don't think there will be any issues. I am concerned as to why my dawes gives me 18 psi at fully extended, u think a result of too short a tubes? Before i cleaned everything it was overshooting and undershooting etc but its ok now 100 miles later. What psi u running on the dawes now?

Cheers

Paul

edited to say sorry my sentences are scatty changing from one topic to another. I am tired

[Edited by paulwadams_my99 - 2/24/2002 7:09:26 PM]

john banks

18-18.5 held boost. Mostly screwed in. Not sure why yours is extended - maybe will be better now after what you have fixed?

paulwadams_my99

maybe, i'll let u know. Can i buy the tubing anywhere else other than buying a kit? I presume that its silicone?

Paul

john banks

I use 3.5mm inside diameter stuff from Falkland - it is quite rigid, and ideal for the job- very tight fit on the Dawes, wastegate and turbo nipple.

FOZ STiV5

Hi Paul,

I have always used Optimax and my region seems fine. It was always hard to tell on my boost gauge what peak boost was because it was off gauge. I thought it was around 1.3 Bar = 18.2 Psi....but maybe it was more. That latter definately gave me knock ....again I though this was just in 5th but when I fitted the knock link I could get it in 2nd and above under hard acceleration. Therefore with Johns advice as an aid I have been playing with the bleed back to the waste gate. I recon that the standard orfice was 5.5mm. I have now installed 0.8mm and I gave the figures earlier...15psi peak and held.

The shock is that only one green LED comes up now on the knock link.... believe me I tested it hard before including motorway running and the dreaded 5th at...umm..... well over a ton. Still only 1 Green LED.

This makes me wonder .....so I will try 0.7 and 0.75mm orifices tomorrow. I think I am running to cautiuosly.....but I will be looking for 2 LEDS under hard acceleration in 2,3,4 and paerhaps a flicker of one Yellow in 5th as full boost kicks in.

Ultimately as I said to John I will settle on conservatism....

L8r

Julian

john banks

"the standard orfice was 5.5mm" I don't think you meant that? I know they are a lot smaller in STis. I really recommend a valve to setup the restrictor size you want. I messed about for ages with the drill/solder/drill routine with 0.1mm increment drills. I found about 1.5-2 PSI for 0.1mm increment. The only 0.05mm drill bits I could source in the UK were for printed circuit boards and take no lateral force before they break. I really needed 1.35mm. My limit though was the PPP ECU starting to oscillate boost at peaks over 17-17.5 PSI, but if I had the orifice too big there was no peak and held boost started to drop. I used a valve and could adjust about 1/2 turn per PSI - very precise. http://www.scoobynet.co.uk/bbs/threa...threadid=56487

FOZ STiV5

Sorry John...its late !! standard was .55mm

lol

Julian