PM-R33

Mine used to do this when the GTRS was running off the stock ecu, would just keep making a shit load of boost no matter what we did. Once the microtech was tuned the problem was gone... Mine is set up to about 19psi at the moment, and holds it fine. However i can run in it as low as 14psi with the profec setup for it. When it hits 5000rpm, does it just violently spike, or does it slowly keep climbing in boost?

When the car got tuned what did the boost pressure graph look like? What power did it make? EDIT: Just found your thread so ill post in there.

Well you obviously missed half the posts in there saying that boost has nothing to do with it, there is no such thing as an RB25 can take x amount of boost. What the engine internals can take before failure in horsepower wise is another story. As said above by a few guys, its power or pinging you need to worry about, not boost pressure.

Yes!! Finally some one else that wants one! I've been looking for months for one and the only way is going to be custom made with a huge cost involved. I dont know why no one makes these, even a universal one for a R33.

http://www.skylinesaustralia.com/forums/Gt...ssure&st=40 Read that thread, page 3 is where most of the information is. It's not boost you have to worry about, its how much power the engine is making and the tune. As for the "afterburn" its just that, exhaust gases containing enough fuel to ignite in the exhaust pipe due to the heat and causing the popping sound you are hearing. Absolutely normal and nothing to worry about, just means the tune is probably on the richer side. And as for the above post i think you are referring the stock turbo being 10-14psi, not how much boost an engine can take because there is no such thing.

BOV Sold

Yep sounds right, maybe invest in a better boost controller so it holds the 16psi to redline instead of dropping off if you want those extra few kw's.

Money transfered man

An interesting thing i just came across, my mate has a highly modified S15 with hks 256/264 cams in it and when it last got tuned the car was down around 80rwkw, no matter what the tuner did he couldn't find the problem. Checked timing and it was 100% set at the correct TDC marks. He than took it to another tuner and they found that the exhaust cam needed to be 4 degrees retarded and the power returned to normal.... Is it possible that on certain setups, the cams aren't ment to be installed at TDC even though most people do? Im gonna go talk to this tuner this week and ask how he set up the exhaust cam and why it was 4 degrees out...

Dont have oversized valves man, head has never been off

PM's replied too

Dam u Why didn't mine work! Yeah power went back to the way it was with the standard cams. It has to be something in the head, only thing we didn't touch.

BOV Sold pending payment.

Lol! If it is indeed HP than thats very low for the mods you have.

Glad you solved the problem man

Correct, simply unplugging the hicas will not stop it from working.

God you better hope it was killowatts......

Thats awesome that the oil company offered that.

Really? I find the profec to be a piece of piss too use. What problems have you had with yours?

Buy my HKS ones, simple http://www.skylinesaustralia.com/forums/Rb...nc-t230152.html Personally i wouldn't bother with reground cams unless they are a lot cheaper than the jap ones.

Bump

What was the viscosity of the oil when it was new?

Incorrect. The maximum boost pressure and quickest spool up your turbo can do is with the wastegate flap wired shut so it never opens. This will cause the exhaust gases to continually run through the exhaust wheel and increase boost pressure as revs increase to a maximum pressure that the turbine itself can make, has absolutely nothing to do with the actuator spring pressure. A turbo running off of an actuator just itself is in no way better than running a turbo off an actuator wired up to an electronic boost controller. With the turbo running just off the actuator it will still slowly creep open and leak of exhaust gases through it and then slowly open the wastegate as the spring pressure is overcome by the boost pressure it can hold (ie. usually 14-15psi on its standard form on a hks item). With the electronic boost controller you can keep that wastegate held shut and then snap open as quick as possible when the desired boost pressure is achieved. This gives a much quicker increase in boost pressure. Test it yourself, wire up a wastegate shut and see how quickly it spools up as compared to just running off the actuator with no boost controller connected.

I played around with my gains and "start boost" function on the Profec last night, kept adjusting it higher until it started spiking over the set boost pressure and it definetely made an improvement in the midrange, just pulled a lot better through the gears and the boost was held a lot better up high instead of falling off a bit.

No reason for it not to work man, turbos are turbos, regardless what they are on. PS: Let us know what power the LS2 makes