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How Much Psi Can U Run In A Rb20det B4 Hurting It

Cyo18r

By Cyo18r,
in Engines & Forced Induction

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Moodles2 Grand Master

Moodles2

Posted
Posted

Anymore than 10psi on a stock RB20 turbo, and the turbo will die. It's not about PSI either, it's about flow. A bigger turbo will outflow a smaller turbo at say 18psi. A RB20 can generally handle 200kw reliably, I generally don't see people pushing more than 250kw.

limpus Mentor

limpus

Posted
Posted

Wrong way to ask a question...its not really the amount of psi that will kill an engine...you can run 10psi which is really low and still hurt the engine if support systems are not up to scratch or the tune is off...

Look towards power figures more as a rough guide...a rb20det will happily live making 250rwkw all day every day if all is well around it...start getting to the higher reaches of 200 like around the 280rwkw mark and you will head into slightly more dangerous ground...that said...plenty or rb20s nowadays are making power in that region and still surviving nicely...and they cop a beating on a regular basis too...

Dose Pipe Sutututu Grand Master

Dose Pipe Sutututu

Posted
Posted

I sexed up my fully stock RB20DET with S1 RB25DET Turbo with 16PSI all day, loved it

only mods were oil cooler, fuel pump, fmic, coil packs, ra ra ra usual bs, ecu remap

Rolls Grand Master

Rolls

Posted
Posted (edited)

It is all about flow and the tune not the psi. Pressure is just a measure of restriction, if you get your head flowed, bigger cams, larger exhaust side of the turbo and larger intake then your psi will drop but you are pushing just as much if not more air. Also you could tune a motor running 6psi so badly that it will cook itself if you try.

A better measure of is how much power the engine can make before it goes bang, assuming a perfect tune. I've seen a few 250kw+ rb20s on here last more than a few years but it all comes down to many factors.

If you are making 220kw with a safe tune with maybe 15-20psi I don't see why you couldn't get a lot of life out of it

I want sumthing that's going to cum on boost around the same rpm as a standed rb20det turbo but a turbo that will Handel say 15 - 18 psi

This is a flawed question, you should be asking what turbo for x rwkw with similar to standard response. PSI doesn't mean anything unless you specify the turbo combination. As 15psi on a small turbo will flow similar power to 8psi on a much larger turbo.

Your best bet is a steel wheeled highflowed rb20/rb25 turbo that aren't too much bigger. The lowest HP rating highflow turbos are probably your cheapest option, otherwise a 2530 etc.

These will all make 200-230kw on roughly 16psi+ although you won't have standard response, it will definitely be laggier. If you want standard response I would recommend an rb25 turbo, these can push 180-190kw with a good tune and 12psi, will only increase the lag by about 500rpm.

Edited by Rolls
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The Dan Grand Master

The Dan

Posted
Posted

I've seen standard CA18's run 56psi and 100+ dyno runs. Standard head gasket, standard NA pistons etc etc.

I didn't believe it when I heard but then I saw it with my own eyes.

What these guys are all telling you is true. You are probably asking the wrong question.

If you want a turbo that can run 18psi and have almost factory response then you need a highflow or a GT2860RS

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