Jump to content
SAU Community

Recommended Posts

i have just finished bolting an rb25 series 2 turbo on my rb20 ceff motor after broken studs and turbo not fitting it is finally on but it seems to not be releasing boost i have the rb20 acuator on the rb25 turbo the thing is i had to move the arm a bit to get it to line up so i am thinking the acuator arm isnt coming out enough to open up the exhuast flap it boosts to stock ten and holds but seems like it stuggles to get there. when it releases it make a weird like blow of value sound but i have the normal plumb back setup but it sounds the the boost is being held in its not the normal psss would it be cause of the actuator isnt releasing help? cheers

Link to comment
https://www.sau.com.au/forums/topic/187844-rb25-turbo-on-rb20-help/
Share on other sites

Please post questions clearly.

What you are saying contradicts itself with the gate not opening & slow boost build - it simply cant occur!

hey sorry about the post i was on my way out, still cant seem to work out why i am getting this weird sound.

mate reckons it could be my stock plumb back is not releasing air so my spring is only opening a little bit.

any other ideas?

Edited by silvercam
the arm need to have free movement try bend it carefully till it can

Im assuming the Act is off your old turbo which had no boost problems so I doubt its stuffed Act

yeah it doesnt have free movement, maby that is the problem will give it a go and get back to ya :P

thanks for the comment

Mine makes a wooshing noise too and sometime if I'm off the gas quickly when on full boost it flutters a bit and a get a nice pop out the exhaust (likely due to the extra fuel being thrown in as a result of the flutter).

117,000km RB20DET (known km's..)

RB25 s1 turbo

FMIC

Greddy Profec B spec2

standard untuned ecu

standard injectors

made 183rwkw @12psi on Hyperdrives dyno today :)

hey car is fine, your right bubba mine is the same. mate reckons i am tripping just makes a different sound becuase it is releasing more air. The gain is huge compared to stock pulls harder through the whole rev range. Think i just mite need a tune dumps a bit of fuel lol cheers for the help

Edited by silvercam

The 25 turbo is shitloads better than the 20 turbo. I think it has shifter full boost probably 1000rpm higher.. with the 20 turbo my car would start spooling about 2000rpm and full boost before 3000rpm, now I'm starting to spool about 3000rpm and full boost about 3500rpm (got a dyno sheet with boost reading, I'll post that up soon).

I will be using this 25 turbo on the 30 to start with while I save for a bigger turbo.. will probably make boost from idle on the 30 :P

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • To plug the hole. The engine plant may not have known whether the car it was going into had a gauge or not. It was a long time ago and the integrations might not have been fully modern. Or they might not have cared because the extra inventory and processes to save a few cents on the sender might have cost more anyway. But please tell me you are not still confusing the idea of a pressure gauge sender, and an oil pressure light switch. The switch will be out there. In a separate hole. Probably with only one wire running to it. Running the light.
    • Blower needs to go low on the exhaust side, displacing the AC and PS, which you have to decide whether you want to keep and how and where to relocate if you do. Electric option for PS is, at least, helpful. Sadly, there is no workable 12V electric AC of any value. Whilst the blower is the last compression step before the throttle, and so it might seem a good idea to have it near the inlet manifold (as mentioned above), you probably want it to go through an intercooler first, so, having it on the opposite side of the car facilitates that air flow path. The turbo discharges into the blower, so proximity of the turbo's compressor outlet to the blower's inlet is nice. But then you might want to intercool that too, before boosting it again....which would probably be a ball ache. Routing pipes out to the front and back could be a bit shit. If there was room for (at least) a small (but preferably larger) water to air core on that side, then that would probably be the best approach. I guess a reasonable alternative would be to locate the blower where the alternator is (more or less, associated with the inlet manifold, per Matt's thought), and somehow incorporate a water to air core into the manifold, sort of like they do for modern blown V8s. The big difference here though is that those V8s have only the one throttle (upstream the blower) and only the one compression step (the blower) and no need for too much in the way of bypass/blowoff valves. Whereas in a twin charged 6, you do need to think about one or two bypass valves associated with the 2 compressors and you would prefer to have the intercooling done before the air has to pass through the throttle. You'd like the throttle to work approx the same no matter what the compression is doing. But if it is located in hot air stream before a cooler, then sometimes the air will be real hot, sometimes it will be quite cool, and the throttle mapping/response will be quite different between those two cases. The throttle, if sized for hot air, would be too large for cold conditions. It's all a ball ache.
    • Package SC on exhaust side. Remote mount turbo. Still a fair bit of room when you get creative on the inlet side of the motor too. Especially if you can get really creative with the welding, and effectively build it into the bottom of the inlet manifold. Would definitely take some design work, and some trial and error, to make sure flow works well still! Might be easier to just start with the Nissan March though... All the work is already done for you...
    • I'll sit down and get a post together 😁
    • The factory oil pressure sender is no longer in the car that's what is confusing me. In the Taarks adapter I have an aftermarket Bosch style pressure/temp sender and the factory temp sender only. Oil pressure is perfect. Where does the factory oil temp sender go to if there were never any gauges? Why was it there from the factory?
×
×
  • Create New...