Quick question

[Mase]

I've got an rb25 turbo on my rb20 and for some reason it runs 0.4 bar stock. The wastegate is sharing a vacuum line instead of me tapping into the cooler piping. Anybody got any ideas?? My thoughts were either the wastegate was playing up or it doesn't like sharing vacuum lines.

thanks

Jayson

[Sydneykid]

Hi Mase, 0.4/0.5 bar that's the standard RB25DET spring rate in the wastegate actuator. RB20DET spring is 0.6/0.7 bar. If you still have your RB20DET actuator swap it over. Or get a boost controller.

[TokyoTaxi]

Mase, another option is to grab an HKS actuator to suit an RB25 Turbo. They don't allow the wastegate to open until 0.9bar. Purchased from BD4's in Sydney I think I paid about $125 new.

[Mase]

Thanks for the advice fellas. Fat32 thanks also but i don't want to run that much boost coming into summer. It's pretty hot under the bonnet of the silvia with the six in there. Sydneykid, yeah i was wondering if i could swap them over or not and was going to have a look at it. Thanks for the advice though. I was just concerned that something may have not been right.

Thanks

Jayson

[TTT]

same thing happened to me.

my $100 bleed valve fixed that problem.

13psi now.

[Mase]

Yeah but last time i put a bleed valve on the thing didn't work. It would almost reach the set boost in 1st, then in the following gears it would try and climb all the way till it hit fuel cut. Tried another turbo smart one and it did the same thing so i wasn't sure whether my wastegate was stuffed or whether it's something that my computer didn't like. I just don't want to take the risk with the new turbo so im going electronic when i can afford it. I think the bleed valve being faulty was a good contributer to stuffin my turbo even tho it only happend a couple of times.

[TTT]

fair enough.

but the 0.4bar boost in standard is normal for the R33 turbo so don't worry.

I have to say though.. when I replaced my RB20 turbo with the RB25 turbo, it still felt better on 7psi than my rb20 one did with 10psi..

take care.

[Mase]

yeah i definately agree on that. My rb20 was running 0.6bar and the rb25 one is running 0.4 bar and it still goes better. Can't wait to turn it up a bit more!

[Mase]

swwweeeet, i just put the rb20 wastegate on the rb25 turbo and it's running 0.7 bar. Replaced the o2 sensor as well and it's a different car!!!!!