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Rb20det Minor Performance Upgrades (update Turbo Selection)


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Made a previous post and since have installed a fuel pump and dump pipe, all that's left is z32 afm, injectors, tune and possibly a turbo, I like the response of the rb25 turbo on my car, full boost by 3000rpmish but limited by the ceramic wheel, what other turbo options are out there? as cheap as possible (excluding China shit)

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That would make a highflowed rb25 turbo on an rb20 fairly laggy then :/ I've heard hks 2530 is perfect for power and response on an rb20 but can't seem to find where to buy one, are there any equivalents of this turbo by another brand?

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or I could find something that I'm looking for? hence the thread lol, it's a street car and I prefer it to be responsive, most times I'm not going to rev it out a ton so responsiveness is a must

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Well, the 2530 to suit RB20 isn't made any more so you're only going to be digging amongst the relics to get one. A HG highflowed RB25 turbo will definitely feel laggier than you want, regardless of the ability to make bulk power. As has been posted above, a highflowed RB20 turbo is less responsive than the original turbo, and it's hard to imagine how you could get a different result. If the turbo has the capacity to make a lot more power than the original, it's likely to be less responsive. Given the step up available, the 600rpm or so of extra weight for boost is greatly compensated by the rush when it arrives.

My experience with RB20s though is that even with the standard turbo, the nothing nothing nothing nothing sudden boost causes traction loss far more readily than an RB25, even with the 25 making much more power. Lightswitch delivery is not the friend of traction. Therefore, waiting longer for an even bigger hit of boost is likely to lead to even more black lines.

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LOL, I am rather opinionated on this topic :)

My experience with RB20s though is that even with the standard turbo, the nothing nothing nothing nothing sudden boost causes traction loss far more readily than an RB25, even with the 25 making much more power. Lightswitch delivery is not the friend of traction. Therefore, waiting longer for an even bigger hit of boost is likely to lead to even more black lines.

Cant go along with that for a second. I have driven on the track and the street probably about 10-15 RB20 powered cars, including drift 180SX.

Now when I say I have driven and offering my comments, I am also offering comments based on the cars respective weaknesses. But one think I can categorically say is that if you have traction problems in your R32 GTSt with less than 250rwkws you have SERIOUS issues with suspension and tyres. If you have traction problems with 300rwkws I say you have average tyres or suspension as the rear end of my car was 100% std arms with bushes for alignment and pineapples with a KAAZ 1.5 diff.

I can show countless vids of my car where traction is never a problem. Here is an R32 with an RB25 on E85 with about 340rwkws on AO50s (he is on SAU so may chime in)

https://www.youtube.com/watch?v=GVbmrwVAcWc

So traction and power delivery....I have actually found RB25s ability to spool turbos far harder/sooner and make more torque actually can cause traction issues before an RB20 would ever cause you problems.

But, to the point of the thread about turbos. I think anyone running an RB25 turbo is selling their setup short. I have driven one with a re-written ECU making 185rwkws odd and another with Nistune that made a tad more, maybe 190-195. For the dollars they were not bad things.

But, I couldnt pick if they were even as responsive as a HKS 2530 or any more powerful than std turbo. I dont doubt the clock todl the story it was faster, but I have to say it didnt feel mid way between std and a HKS 2530. It felt closer to std.

Seat of the pants left me thinking that you really need a 320-350hp frame turbo to get the R32 over 210rwkws before I would say it is a worthy upgrade over the std turbo and the 150-160 it can provide. If you could run 18psi on the R33 turbo it would be a good thing. Sadly you cant run that boost

HKS do still sell the 2530 as a kit. try part number 11004-AN007. For a punchy, bolt on 220-230rwkws they are hard to go past. The price for a new kit can make you bleed...but here is a car I drove in a 3 day rally (thanks Russman) and has always been interesting to compare to my TD06-20G setup. Though in this video is driven by Russ, who can drive way better than me.

https://www.youtube.com/watch?v=ITBatzu3TlY

That video is a std RB20 with 256 cams (they make no difference in IMO) and a HKS2530 tuned to about 230rwkws. Gut full of boost that falls off at high rpm but you can see running AO50s is actually quicker than the RB25 powerd vid shown above with waaay more power. Russ's car at that time was hardly a lightweight race as it is today, and was close to what I would call a road car with seats, carpet, sound deadenging etc.

Yes, different drivers and cars...but all show that at various power levels traction is not a problem. And on the track vs street cars need different things.

RB25s make an R32 so much nicer on the street. But with bumps and crap roads etc I find they are more traction limited and their main benefit is how they make them such a nicer car to drive around off boost and onto boost.Outright performance? It is more a matter of how much boost you are running and ultimate power as thats what gives you the torque to accelerate in the rev range up top when you are up it...and the difference is often not very pronounced IMO

If I was you sama1500 I would buy a blown HHS2530 or 2540 cheaply. You can get them for about $250-350. All you want is the T3 exhaust housing. Then I would go and buy a GTX2860, use the HKS turbine housing and bolt it on for a good little punchy turbo that can feed the lil RB20 20psi and make good power. 230-250rwkws

I have not seen that many Hypergear results so?!?! If he can give you HKS2530 response and make 250rwkws on std manifold and internal gate then that is obviously an option, likely cheaper

Oh...and that engine or Russman never blew after all that abuse and track work at boost. I think during the Dutton Rally he was running 22psi falling down to about 15psi up top and when he pulled the pin and went RB25 it was still a perfectly healthy engine. Tuned right, you cant hurt a healthy RB20 with the power you are going to make out of something like a 2530 or GTX2860

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thanks a lot roy, i dont really plan on pushing the limits of the rb20, its a streeter so reliability is important to me, 220-230kw is the max i would be wanting out of my car, it really is a shame you cant run the rb25 turbo with more boost otherwise i wouldnt even have this dilemma haha, the cost of a new gtx2860 plus a blown 2530 does seem a fair bit more than the hypergear option but i'll definitely keep it in mind

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LOL, I am rather opinionated on this topic :)

I'm not going to argue with any of that for a second. My point is more about street driving and definitely more about the whole question of "at what point after I open the throttle will this bloody thing suddenly start making boost while I'm turning this corner and throw the back end towards the kerb?", which is the way that I think RB20s behave. There's just so much doubt about when it will break traction. Driving on the track, where you are going into corners at near max speed and rolling on the throttle (or throwing it all in depending on the corner) is a different world.

The difference in what you get with a 25 (in a 32) is exactly as you say. In addition, when you open the throttle with an RB25 you actually get meaningful acceleration while still off boost. I find that when boost arrives the transition is easier to control.

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Dont worry abot de-tuning or leaving something in reserve for reliability. Trust me when I say if :

A) you compression check your engine and the cylilnders come back happy

b) runa godo quality oil pressure gauge and engine pressure is in line with healthy

c) you run Castrol Edge 10W60

Properly tuned you wont have to worry about reliability of your RB20. They are strong engines at that power and what will give you reliability is servicing. Not worrying about the power ceiling of the std engine. My engine died for instance due to a coolant hose under the plenum splitting. y poor proud std engine that I abused but loved dies in peak hour traffic because it overheated and the head gasket started weeping. (though I still drove it for 6 months like that)

Others die because of tired, lazy fuel pumps and your rail pressure dropping. Or once started to be modified are poorly modified or tuned. Making sure your hoses, lines, filters and ancillaries are all in good order is what will make your car reliable, not whether its making 210 or 250rwkws ... LOL ALL IMO :)

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im not chasing max numbers and my original goal was to have a turbo that doesnt blow up when i put more boost into it, 250kw is well above my original goal in power anyway i'd be happy with 220 as that gives me more than enough to have a good time with although having the option to go up to 250 is nice, whereas on the rb25 turbo i'd be lucky to get 200 and thats with the constant worrying of if the turbo might blow

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