R31 Rb20Det Track Car

[Leeroy94]

I have a stock rb20det with a stock turbo down pipe to the ground. No exhaust.

Would this upgrade be a bad idea?

http://www.ebay.com.au/itm/400455487571?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

Feel free to voice opinions, and other possible options, however I am on a budget

[GTScotT]

Yes, they are shit.

You are likely to run into boost control issues and poor performance.

Get a bell mouth dump.

[iruvyouskyrine]

I have a stock rb20det with a stock turbo down pipe to the ground. No exhaust.

Would this upgrade be a bad idea?

http://www.ebay.com.au/itm/400455487571?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

Feel free to voice opinions, and other possible options, however I am on a budget

JJR bell mouth from Justjap will set you back around $170 from memory. It is a much much better choice.

[iruvyouskyrine]

justjap.com/store/product.php?productid=18178

[Leeroy94]

Ok thank you guys so much for the info! I'll look into the justjap dump pipe

[Leeroy94]

Is this upgrade worth $207? I'm not running an exhaust, how much power gain should i expect once installed?

[XRATED]

yes.... 6-10 ish kws.

[Leeroy94]

I can source an rb25 turbo, will that dump pipe still bolt on if I upgrade the turbo?

[iruvyouskyrine]

As long as it is a standard Nissan turbo yes.

[Leeroy94]

What power increases should I expect from swapping over a rb25 turbo (with the rb20 actuator at 10psi)?

[GTSBoy]

That depends on what you're doing for engine management and fuelling. I will ignore the 10 psi part for the moment.

In general, on an RB20 that is running standard everything and maxing out the standard turbo, you 'll get to 160 - 170rwkW and the injectors will be maxxed or close to it, the AFM will be reading 5V or close to it, the turbo will be at 14 psi and running on borrowed time before dying. If you put on an RB25 turbo it will make the same power at a bit less boost, because the turbine housing is that little bit bigger. You might reach the same power levels and hence the same injector duty cycle and AFM voltage at only 12 psi. So no change. Maybe you'll scrape a little more power out of it if there is still some room in the injectors and so on. 180rwkW is a fairly common result.

To get any more you need to be able to keep up with the fuelling and really need to be able to tune the ECU. And then you're pushing an RB25 turbo up to 14 psi where it is just as likely to go bang as any other Nissan ceramic turbo. Maybe it will be a little less prone to self destruction running 14psi into an RB20 than it would on an RB25 because the shaft speed will be a bit less to make the smaller amount of flow at that boost. But it really is a game of chance when you wind them up.

Would I do it. Yep. Would I expect the world to be a different place afterwards? Nup. On 10 psi it will make a little more power than the RB20 turbo, again maybe 10 rwkW, maybe less. You really need to add some boost to get a sizable benefit (with increase in risk of course).

Edited September 12, 2013 by GTSBoy

[Leeroy94]

This is what I know of the engine in my drift car

Rb20det

Huge FMIC, too big IMO (bought it that way)

Hks bubble air filter (brand new insert)

3" bell mouth dump pipe as stated above. (Not installed yet)

Some sort of resistor wired up to something near the intake that supposedly makes the car think its running at 30 degrees so it pumps more fuel in (previous owner)

I know nothing about how to tune an ecu.

I'm not looking for huge power. Just another 15-20kw to make a little more drive to make it easier to link corners.

Note: I have two turbo options, option 1: rb25 turbo $200 or option 2: r34 op6 turbo for $300

Or which direction should I go for that extra 15-20kw that will be the cheapest overall

[Ben C34]

That resistor sounds odd. More fuel is the last thing you want on an untuned rb ecu. I would suggest getting a proper tune done with a nistune board. That would yeild best bang for buck

[D.I.Y. Mik]

The Nistune is nice and cheap too.

Fuel pump and injectors might help.

Im getting 180 kw safe and reliable with all that on 14 psi rb25 turbo.

Now the turbo is the weak point. Cant go any more boost.

JJR steel bellmouth works good for me, dont go stainless, its a waste of money.

Op6 turbo is good cos when you want to hi flow, it has the good housing.

But think..... if you want cheap, you get the tune once.

That means working it all out, install all the bits, and get the Nistune.

[Leeroy94]

I've put the new dump pipe on but the old dump pipe only had 2 of the 6 bolts in it does anyone know what size bolts I need to get?

[Ben C34]

Cos you aren't running an exhaust, those 2 bolts would hold the dump on good enough, but for reference they are M8. 40 long would do it. (standard pitch, 1.25)

[Ben C34]

spazzed out there. dump flange would be about 12 thick so you would want a 25 or 30 long bolt.

[Leeroy94]

Thanks mate. Much appreciated