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Rb20 Owners Past And Present, I Want Your Thoughts And Opinions About Some Things


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Hello

Everyone who has or has had a RB20 engine in a R32 GTST, I have some questions and want your opinions about some things.

I have read some people think that the RB20 is rubbish and not so good of a engine to get good power. I think that it can be done.

I will buy a GTR but for now I want to push my RB20 as far as it can go somewhat.

RIght now I have a RB20 with a series 1 RB25 turbo from a R33. I have a MINES boost up tune, full 3" from the turbo back exhaust, intake, sports cat, Blitz return flow intercooler.

The car isn't bad. I start boosting around 2500rpm depending on how I hit the gas, and the car gets really moving around 3000-4000 RPM if I am hitting the gas hard.

What are your experiences with the RB20 over 300hp? How is your response? Acceleration? Who has touched the inside of their engine? Has it made a difference?

I am thinking about putting forged parts in the engine since I can get good parts from the states and Australia which is cheaper than buying here in Japan.

Also who has bored their engine to 2.2 liter or 2.4? How is it?

Who has installed adjustable cam gears or/and Pon Cams? How was the car after that?

My planned updates will be; NIstune computer, 550cc or higher injectors, bigger turbo, adjustable cam gears or/and Pon Cams, new oil pump(original is fine but the car is 25 years old), update with new hoses, etc. Maybe a Plazaman intake manifold, forged internals, etc.

I think a responsive good street 400hp or close to it can be had without breaking the bank. After that I will buy a GTR.

I have never visited Australia, but I assume that their are lots of long stretches of big open roads. Here in Japan, its not like that. So I am looking for good street power and some decent highway power. I will take the car to the track sometimes just to go fast.

I have read though pages of post here but haven't really found the answers I am looking for.

So what is everyone's opinions and experiences with the RB20 ?

Edited by yoshiii335

RB20 Dyno thread would be a good start.

You can reach your power goal without opening the motor (i.e forged internals).

400hp will not be responsive. I've got around that (at the motor) and it makes full boost at 5000rpm. It really does nothing below 3800rpm.

But, drive it like a 2 litre engine with a (too big) turbo and its ok. Need to use alot of revs, but thats ok, becasue RB20's love to rev.

Before modifying an RB20 you need to be ready for the lag. It is way to easy to throw alot of money at an RB20 and not be happy.

If you can live with no real forward thrust below 4000rpm, then go for it.

I notice from other threads you've stated changing motors to a rb25 or 26 is not an option, so, if you are going to buy a gtr in the future, and just want some more from your RB20 for now:

Don't open the motor

Don't stroke it (2.2 or 2.4)

Don't do cams.

Do get a hypergear highflow (or similar bolt on turbo, HKS 2530, 2535, maybe some modern garret options, I'm unsure of specs)

Nistune and injectors

Deal with the lag, be happy that you've made around 400hp about as cheaply as possible.

Lastly, (again) look at the RB20 dyno thread, it will tell you what mods people have done, and the result, after looking at a lot you will quickly see some people do a lot of mods for no better result than others that keep it simple.

Edited by CEF33Y

install a massive dose pipe, hektics.

serious note, they're gutless, make crap all torque and don't waste your money modding it.

Motor out, donate to a marina as a boat anchor and NEO in.

  • Like 1

I love RB20's. Reasonably gutless but you make up for that by thrashing the absolute f**k out of them and they love it. I still miss mine and sometimes regret going to a 25 and then a 25/30.

The best part about them is the sound though. Soooo gooood.

  • Like 1

RB20 Dyno thread would be a good start.

You can reach your power goal without opening the motor (i.e forged internals).

400hp will not be responsive. I've got around that (at the motor) and it makes full boost at 5000rpm. It really does nothing below 3800rpm.

But, drive it like a 2 litre engine with a (too big) turbo and its ok. Need to use alot of revs, but thats ok, becasue RB20's love to rev.

Before modifying an RB20 you need to be ready for the lag. It is way to easy to throw alot of money at an RB20 and not be happy.

If you can live with no real forward thrust below 4000rpm, then go for it.

I notice from other threads you've stated changing motors to a rb25 or 26 is not an option, so, if you are going to buy a gtr in the future, and just want some more from your RB20 for now:

Don't open the motor

Don't stroke it (2.2 or 2.4)

Don't do cams.

Do get a hypergear highflow (or similar bolt on turbo, HKS 2530, 2535, maybe some modern garret options, I'm unsure of specs)

Nistune and injectors

Deal with the lag, be happy that you've made around 400hp about as cheaply as possible.

Lastly, (again) look at the RB20 dyno thread, it will tell you what mods people have done, and the result, after looking at a lot you will quickly see some people do a lot of mods for no better result than others that keep it simple.

Boost to max. Revs to max.

Off into sunset.

Still disappointed.

I love RB20's. Reasonably gutless but you make up for that by thrashing the absolute f**k out of them and they love it. I still miss mine and sometimes regret going to a 25 and then a 25/30.

The best part about them is the sound though. Soooo gooood.

By revs you mean by keeping the rpms up constantly in 3000-5000 range?

I notice when I take off from a stop not flooring the pedal but just normal driving, I hit 3000 rpm within about 4-5 seconds. So if I have my car to where it doesn't get really going until 3000-4000 rpm, than that wouldn't be so bad. But wouldn't any upgrade to turbos, cams, etc help with building up more torque? I am not trying to become torque man, I just want a fast car, which can keep up with Toyotas, evos, etc.

If you want a fast car, to keep up with toyota's and evo's an RB25 will produce a better result.

If you increase the turbo size at all, you shift the power and torque up in the rev range. Might get a little back with cam gears.

But a 400HP RB20 will need a thrashing to feel "fast"

On the subject of toyota's, I drove a mates newly aquired JZX100 chaser.

(VVTI version of the 1jz, and is manual)

Holy smokes, there is real forward thrust from 1800rpm. It hauls.

If you want a fast car, to keep up with toyota's and evo's an RB25 will produce a better result.

If you increase the turbo size at all, you shift the power and torque up in the rev range. Might get a little back with cam gears.

But a 400HP RB20 will need a thrashing to feel "fast"

On the subject of toyota's, I drove a mates newly aquired JZX100 chaser.

(VVTI version of the 1jz, and is manual)

Holy smokes, there is real forward thrust from 1800rpm. It hauls.

ok

So what do you use your car for, mostly track? Do you like the power you mentioned your car has?

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