Rb20det Minor Performance Upgrades (update Turbo Selection)

[hypergear]

Fully stock RB20det, bolted on using factory bits. P98 fuel, 227rwkws @ 17psi. ATR43SS15.

[Roy]

Stao...To help me understand a few things what size wheels and housing does that turbo run?

Is that optimum with cam gears and the right bolt ons? You say full stock. Do you mean std intercooler, exhaust/dump etc? Or do you mean std internal engine? That graph doesnt appear that different in response to a GT-RS

I know its hard to compare a full setup with a bolt on upgrade...but, a TD06-20G like mine is crudely a 55/65mm turbine with an 8cm (read it is approx 0.57-0.62ish) with a 52/68mm compressor.

A turbo sized for around 210-230 only needs a 58 to 60mm compressor like a 2530. In which case you can get them to spin up harder than that graph? This is an rpm/boost plot for my 20G and a GT-RS

[sama1500]

full boost by 4000rpm does seem a little laggy for my application, maybe i should opt for a second hand 2530 in that case? or a garret turbo of about equivalent size?

[sama1500]

http://www.ebay.com.au/itm/GARRETT-NISSAN-SKYLINE-R32-R33-R34-BOLT-ON-GT2860RS-BALL-BEARING-RB20-RB25-350HP-/140961296372?pt=LH_DefaultDomain_15&hash=item20d1f2aff4
would something like this be better for my application? i honestly dont know much when it comes to turbos and sizing etc but this is apparently the garrett equivalent of a hks 2530

[Roy]

It has been years since I looked at the T3 housing options for a GT28 frame turbo. Once upon a time they never seemed to perform as well as the HKS range due to HKS offering their turbos in a good performing T3 housing. Hence my suggestion to grab a used HKS turbo just for their housing

That housing looks like the HKS housings, so perhaps someone can speak to whether there are finally good performing T3 GT28 housings out there. Discopotato and a few other SAU forum guys are freaks with what they know re housing options...fingers crossed they read this thread.

[hypergear]

ATR43SS15 runs a .64 rear, 55mm turbine and a 64mm billet comp wheel, which is some thing that we also makes for the SR engines. In which Rb and SRs has some similarities. The SS15 on a worked SR have maxed out at 281rwkws on P98 fuel, which the 2530 can not reach.

Either way, the GTRS or the SS15 is made to be an internally gated bolton turbo, and it has to be forgiving on the exhaust side for it to perform, that is not required for an externally gated turbo. Plus been externally gated it would have given a more free flow manifold, gate that also helps in power making. If a high mount system will be used, you can use our Sl20.5 in a 8cm turbine, which will out perform a standard 20G with similar response.

[sama1500]

i dont plan on going high mount, ive heard great things about the discopotato turbo on sr's in terms of power and response for street use, so in theory if the housing is as good as it was on the 2530 this turbo should perform as well?

[hypergear]

It will out perform a 2530 in terms of power with similar response.

[sama1500]

for me response is a priority to power and 4000rpm until full boost is just not what im after, the 2530 from what i hear is more responsive and easily makes the power im after, if the garrett version turns out to be good as well i might opt for that being new and a similar price to the hypergear stuff

[Missileman]

You wouldn't be the first to try and eat their cake too...

So what supporting mods do you have?

[sama1500]

I'm just trying to find a turbo to suit my application I don't see the problem with that? existing mods are front mount, turboback exhaust, 255 fuel pump, pod filter, and coming soon a z32 afm, injectors and a nistune

[Missileman]

See if you can find someone on these forums who can take you for a drive with a RB20 Hiflow, before you decide on turbo, what ever you do listen to Roy and Stao, their advice could save you a lot of money.

Personally I think you're worried too much about lag, the cheap option is usually the right option with a RB20

200-220rwkw you just might squeeze that out of the stock injectors and AFM

[sama1500]

I'd rather not push the standard injectors and afm to their limits, I'll try, if an rb20 highflow has similar response to a 25 turbo that would be fantastic

[Roy]

ATR43SS15 runs a .64 rear, 55mm turbine and a 64mm billet comp wheel, which is some thing that we also makes for the SR engines. In which Rb and SRs has some similarities. The SS15 on a worked SR have maxed out at 281rwkws on P98 fuel, which the 2530 can not reach.

Either way, the GTRS or the SS15 is made to be an internally gated bolton turbo, and it has to be forgiving on the exhaust side for it to perform, that is not required for an externally gated turbo. Plus been externally gated it would have given a more free flow manifold, gate that also helps in power making. If a high mount system will be used, you can use our Sl20.5 in a 8cm turbine, which will out perform a standard 20G with similar response.

Thanks for clarifying. So the RB20 results, did the engine have a full exhaust, FMIC and a decent tune? What do you mean by completely std?

[hypergear]

Means the engine is un-opened. Standard cams, standard cam gears, standard pistons, rods, and every thing else.

[sama1500]

thanks for all the replies guys, i do plan on getting the car tuned after putting in injectors and a z32 afm on my current rb25 turbo to see what power it makes and then re-tuning it once i have bought another turbo, after the first tune i'll have a dyno graph for reference as well which will make turbo selection easier

[Roy]

Up to you...but why pay for two tunes? Put that money towards the best turbo you can afford...not keeping your tuners dyno running/funded.

Stao...what turbine housing differences are there between the T3 one you make for the RB20 and the T25 you make for the S15?

[hypergear]

Its actually an T2x turbine housing. T2x .64 is the only housing that provides good drive ability working with Rb20det engines. So we made a drawing and worked out a method that modifies a Standard T2x .64 turbine housing into a Nissan Rb Bolton turbine housing with a massive internal gate. That enables us making any RB bolton turbos using any T2x based wheels for better response. The SS1PU for Rb25det follows the same pattern.

[sama1500]

at the moment my car isn't tuned at all, by getting it tuned it will run nicer, i'll make a bit of power and ill have a dyno reading of what everything is doing, peak torque/power/boost levels, with that info i can select a new turbo with much more information to go on, i also never originally planned to upgrade my turbo until a much later stage anyway, i might even be happy with a lower level tune for quite a while who knows

[XRATED]

rb20det is a well trodden path.

Personally the most enjoyment I got out of any of my rb20 combo's was a stock turbo (with good supporting mods- intake, full exhaust, small cooler, pump, plugs etc), safc tuned r32 with 4.4 gears. Light revvy and fun.

My suggestion along with everyone else, is keep it cost effective and fun. Don't chase big power and don't think for a minute your going to re-invent any wheels.

Cheers

J.