GTRman1992

Gson plumb back are better as the air going into the engine is measured by the AFM's, so if you vent it to atmosphere your car will run rich on gear changes as the ECU thinks that air is still in the system. There are ways to fix this but its all too hard only for the swissssss noise that will get you a defect.

I think the best result would be to submerge it in liquid cooled by one of those electronic petler devices. YOu could cool it down to around 10deg and get a big advantage.

Sometimes its more fun that way !

I'm keen. Yet to be Dyno'd. Would have to be a 4WD unit.

GTST - Yes I have no BOV at all. The factory ones are blocked off. Roy. I agree when you say everyone has an opinion on the subject. BOV is almost like having a religeous discussion. Soon I will be setting up a pressure sensor with high speed logger in front of the turbo outlet. This will measure both the pressure wave some claim and the back on boost response time. I will do it on a GTR that have BOV's so we can shut them off and get a true final answer on the subject. Roy, On your loss between gear changes, I think it is the bigger turbo. As I said earlier I spin the wheels from 1st to 2nd and 2nd to 3rd, so I cannot understand the powerloss arguement. Will see soon anyway.

I'm also interested in the details. I think you would get good gains. Thats what it is all about, we have intercoolers to cool the charge, water injection to cool stuff, why not cool the fuel also.

The boost isn't a problem if the engine is tuned to handle it. You need the right fuel delivery and timing adjustment to stop the engine destroying itself. This must be set up be a professional. I know of 3 guys who have smoked their engines just playing with the boost alone.

What track do you drive A,B,C,D ? I think B is the most common, along the pits with the hair pin, sweeper up past the hut then down the hill. What are your lap times like ?

As I said above, my car spins the wheels from 1st to 2nd and 2nd to 3rd so I don't believe the loss of power theory. I run RE-540S semi slick tyres so the grip is high ! Read my item above. Anyway, what flutter noise. Have you run the car without the BOV and heard it ? The pressure you hear being released is your normal boost pressure. The way I see it is that if you vent it off then you have to build it up again before being on boost again. So a BOV would actually slow down the boost between gears.

What is the story with the Morgan Park track days ? Do you guys organise one ?

There is no load on the engine. Therefore not much air flow.

I don't believe the BOV propoganda (only needed with massive turbo's). I don't have one at all, run 20PSI boost and spin the wheels from 1st to 2nd and 2nd to 3rd. So there is no loass of power without one. Also it has been like this for 3 years and all is fine. If you have a think about it, a pressure wave from the throttle body running all the way back down the induction system (full of 90deg bends which call big losses on pressure waves in a compressible medium) through the intercooler core and hitting the turbo blades with any impact is nonesense. Especially as the medium it is travelling in is collapsing anyway. Also consider the volume of air in there, for a pressure impact you have to raise the pressure of that entire volume, with a turbo that is no longer being spun by exhaust gas for the 2tenths of a second the throttle is shut. I'm just not a believer.

Rule of Thumb Kw = 0.75Hp. (e.g. 400Hp = 300Kw) Drive Train Losses 30%. But as sewid said, nothing beats a dyno run for the truth.

I'm not a BOV believer. I have been running 20psi for 3 years without a problem. The car spinns the wheels beteen 1-2 and 2-3 so I don't know what power I'm missing.

AFM give more precise control. You would have to be sure your making too much power before getting rid of them. The 80mm Z AFM's are huge !

Damn. Sounds like fun, have to wait till the beast is fixed. Hopefully out with you guys sometime in feb

Faulty Oil Pressure Sender. Left head light plays up. Just need to flick the switch a few times. Climate control sometimes does funny things. Appart from that, its da bomb.

Yes, I can name at least three dudes I know who installed a turbo smart bleed valve and blew up there cars. You cannot just wind up the boost without considering a lot of other parameters. Best to set the boost with proper tune and leave it alone. I look forward to continued discussion re my setup.

Yep.

I know what it does. Just seems to me from reading above and elsewhere that people have no end of headaches setting up these systems, EBC and bleed valves. Doesn't seem worth the hastle to me, thats all.

I thought it was the other way round, don't you tune on a dyno (get mixtures close in a controlled environment) then fine tune on the road for final driveability ? That's just what seems to happen in the magazines.

I've had EBC GreenStuff on the front and Black stuff on the rear for almost two years. Got new slotted rotors as well as the drilled ones cracked. I think they are fantastic, I used to get brake fade about 1/2 way down the back of Mountain runs and now they are 85% fade free. Also on the race track I find them the same. I'm going to install some brake ducts to hopefully get that last 15% as I cannot afford the Brembo upgrade We put some on a mates HSV and got a great result.

How about setting the boost with the control arm to the wastegate and leaving it alone. Power is controlled by the right foot right ? Mine is set at 20psi and thats it. If its raining I don't nail it. The only purpose I've seen so far for adjustable boost is so that when I beat a dude in a "traffic light grand prix" he can say "but I wasn't runniing full boost" or "I was only running 12psi" etc. Oops, I can feel a flogging from Sydneykid coming

Does Gavin / Gilmour have 4WD dyno ?

Ok, I thought more boost = less engine life. So you say more boost as long as air temp is ok. Interesting. Maybe I can aim for my original 23psi - 25psi limit. My turbo's have an interesting background. They are genuine ex-gibson units. Back when the GTR was banned from racing, Gibson motorsport had an action and unloaded all their stuff, anyway someone I know bought a set of turbos and put then away for a special day. That day never came and he offered them to me. I had them rebuilt etc. So they should be good for 600HP at 23psi boost as that is what I think Gibson was running. The article on the CAMS said 4deg retard on exhaust and 2deg advance on the inlet was ideal.