Jump to content
SAU Community

What turbo for my RB20DET buildup?

rb20-calais
 Share

Recommended Posts

rb20-calais Rising Star

rb20-calais

Posted
Posted

Guys,

I have done a lot of searching and reading but there is not much information reguarding results with GT** turbos, mostly discussion is about the HKS items.

I dont have a turbo I sold it as I was gonna do a rb25 turbo but i have decided to do the lot and have taken my car off the road.

I really want to hear your imput on the differences between the GT25/28 and different driveability. The GT25 is rated @ 400hp and I was told it will make 250kw@wheels, but @ what boost? I was looking for around 220-230kw@wheels to be daily driven and maybe wind it up a bit for the strip. I have a Wolf 3D V4 with hand controller.

To be able to fit the GT25 to my car I was quoted the following. $100 for the adapter plate welded to old manifold, $250 for 3" dump ($300) if i want a screamer and $220 for the lines(braided). Is this a good price? It was from Ricol Performance.

Any input would be greatly appreciated!

Thanx

Evan

P.S. I will have a cooler, fuel, etc to run the numbers... no comments on how its not just a turbo that will get me power :D

Link to comment
https://www.sau.com.au/forums/topic/19428-what-turbo-for-my-rb20det-buildup/
Share on other sites
Steve Grand Master

Steve

Posted
Posted

Evan,

I have only been in a RB20 with 2530, not 2835, so I wont comment on the latter.

the car in quesion put down about 230rwkw at 1.2 bar, came on boost quicly and pulled hard through to red line of 8200rpm. these turbos apparently hit peak efficiency at 1.5-1.7bar, so there would be a bit left. It was a drift car, so boost came on pretty hard.

With regard to fitting, the 2530 can come in a t3 form that will bolt straight up to a stock manifold (as it was on the above), so adaptor plate shouldnt be necessary. $250 seems pretty cheap for a dump. $220 for braided lines is pretty good to.

BTW, I have seen a 2530 second hand recoed, with polised comp housing and braided lines, wastegate, t3 flange for under 2k - which is cheaper than a high flow, and therefore IMO are pretty bloody good value for money.

rb20-calais Rising Star

rb20-calais

Posted
  • Author
Posted

yeh,

I think a 2530 would be great but I am a bit sceptical buying a second hand turbo from japan. There is one at hikari for $1780 with a t3 flange although in the pic I cant see hks on the turbo so i think it is a garrett item... anyone can confirm?

2530 sounds perfect for what I want and I would buy a second hand one if the condition was known.

Evan

Evan

rbs13 Community Regular

rbs13

Posted
Posted

i would go 2540.. if you want more hp later.. which im sure you will :D.. you could get a xtr or what ever equilavent and get them to build it to your specs.. the only real good thing about hks turbos over their garret base is that they come into their own world when boost is increased.. if you only wanna run 1.0 bar i would stick with something garret produce, the hks badge adds about 600-1000bux! you could get the same exhaust housing the 2530 uses (same size a/r ratio or what ever) and then put on a bigger compressor housing to get a quick boost response/spool up and with the bigger compressor housing it will flow a bit more at the top.. talk to a turbo specialist about your wants and needs.. you could end up happier..

Steve Grand Master

Steve

Posted
Posted

water connections are usually pretty easy to souce, somewhere like enzed, or pritec? (i think). Without knowing what trim the wheel is, might be a bit hard to guesstamate.

What did they tell you it was capable of when you bought it? Did they tell you it is a straight fit?

rb20-calais Rising Star

rb20-calais

Posted
  • Author
Posted

i have opted to go with a gt25, i am undecided on if i should go the 400hp or 440hp model, i realise an adapter plate will be around $100. The 440hp model is only like $100 cheaper... but will be laggier? will the 400hp model support 250kw@wheels... i am undecided... i have been told the 440hp model will hit full boost around 3500rpm as i know someone who has one on a ca18 and it hits full boost at 4100rpm

thanx

evan

Cubes Grand Master

Cubes

Posted
Posted

You will be pushing to be hitting full boost at 3500rpm.

A RB25DET turbo hits full boost by 3500rpm, you will be most probably be looking at the positive side of 4000rpm for full boost with any turbo that makes decent power on the RB20DET.

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
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • myrbgivesmeheadaches
      RB25DET NEO Cylinder Head

      By myrbgivesmeheadaches · Posted

      Did this end up working? Did you take some pictures?
    • Duncan
      V37 Suspension change

      By Duncan · Posted

      And finally, the front lower mount. It was doubly weird. Firstly, the lower mount is held in with a bracket that has 3 bolts (it also acts as the steering lock stop), and then a nut on the shock lower mount itself. So, remove the 3x 14mm head bolts , then the 17mm nut that holds the shock in. From there, you can't actually remove the shock from the lower mount bolt (took me a while to work that out....) Sadly I don't have a pic of the other side, but the swaybar mounts to the same bolt that holds the shock in. You need to push that swaybar mount/bolt back so the shock can be pulled out past the lower control arm.  In this pic you can see the bolt partly pushed back, but it had to go further than that to release the shock. Once the shock is out, putting the new one in is "reverse of disassembly". Put the top of the shock through at least one hole and put a nut on loosely to hold it in place. Put the lower end in place and push the swaybar mount / shock bolt back in place, then loosely attach the other 2 top nuts. Bolt the bracket back in place with the 14mm head bolts and finally put the nut onto the lower bolt. Done....you have new suspension on your v37!
    • Duncan
      V37 Suspension change

      By Duncan · Posted

      And now to the front.  No pics of the 3 nuts holding the front struts on, they are easy to spot. Undo 2 and leave the closest one on loosely. Underneath we have to deal with the wiring again, but this time its worse because the plug is behind the guard liner. You'll have to decide how much of the guard liner to remove, I undid the lower liner's top, inside and lower clips, but didn't pull it full off the guard. Same issue undoing the plug as at the rear, you need to firmly push the release clip from below while equally firmly gripping the plug body and pulling it out of  the socket. I used my fancy electrical disconnect pliers to get in there There is also one clip for the wiring, unlike at the rear I could not get behind it so just had to lever it up and out.....not in great condition to re-use in future.
    • Duncan
      V37 Suspension change

      By Duncan · Posted

      Onto the rear lower shock mount. It's worth starting with a decent degrease to remove 10+ years of road grime, and perhaps also spray a penetrating oil on the shock lower nut. Don't forget to include the shock wiring and plug in the clean.... Deal with the wiring first; you need to release 2 clips where the wiring goes into the bracket (use long nose pliers behind the bracket to compress the clip so you can reuse it), and the rubber mount slides out, then release the plug.  I found it very hard to unplug, from underneath you can compress the tab with a screwdriver or similar, and gently but firmly pull the plug out of the socket (regular pliers may help but don't put too much pressure on the plastic. The lower mount is straightforward, 17mm nut and you can pull the shock out. As I wasn't putting a standard shock back in, I gave the car side wiring socket a generous gob of dialectric grease to keep crap out in the future. Putting the new shock in is straightforward, feed it into at least 1 of the bolt holes at the top and reach around to put a nut on it to hold it up. Then put on the other 2 top nuts loosely and put the shock onto the lower mounting bolt (you may need to lift the hub a little if the new shock is shorter). Tighten the lower nut and 3 upper nuts and you are done. In my case the BC Racing shocks came assembled for the fronts, but the rears needed to re-use the factory strut tops. For that you need spring compressors to take the pressure off the top nut (they are compressed enough when the spring can move between the top and bottom spring seats. Then a 17mm ring spanner to undo the nut while using an 8mm open spanner to stop the shaft turning (or, if you are really lucky you might get it off with a rattle gun).
    • Duncan
      V37 Suspension change

      By Duncan · Posted

      You will now be able to lift the parcel shelf trim enough to get to the shock cover bolts; if you need to full remove the parcel shelf trim for some reason you also remove the escutcheons around the rear seat release and you will have to unplug the high stop light wiring from the boot. Next up is removal of the bracket; 6 nuts and a bolt Good news, you've finally got to the strut top! Remove the dust cover and the 3 shock mount nuts (perhaps leave 1 on lightly for now....) Same on the other side, but easier now you've done it all before
×
×
  • Create New...