Rb20 Turbo.

[LTHLRB]

a four cylinder will spool up larger turbos faster than an equivalent sized six cylinder so i would be cautious comparing SR20 results.

come on man, u know the rb20 runs 6 cyls rather than 4 so that means SLIGHTLY quicker spool, also mixed with what the engine is built to do etc

a 3071r will be MORE responsive on a rb25det and rb20 rather than the sr20, lets say.. equiped with cams?

but personally i would do a 3071r with an external and .63 exhaust.. that would be pretty sweet.

Edited September 8, 2007 by LTHLRB

[Roy]

so a gtrs will spool faster on a 4cyl sr20det than a gen 3 5.7ltr sporting a gtrs? come on man, u know the larger capacity means quicker spool, also mixed with what the engine is built to do etc

a 3071r will be MORE responsive on a rb25det and rb20 rather than the sr20, lets say.. equiped with cams?

but personally i would do a 3071r with an external and .63 exhaust.. that would be pretty sweet.

Thats not what he was saying. he is saying the longer stroke and bigger bore 2L 4 cyliner will spool a turbo better then the smaller bore, shorter stroke RB20. Where did you come up with 5.7L V8s from????

Dale...yeh, my point is, a short stroke 2L six is never going to be king under 3,000rpm, so no point trying to size a turbo to get low end grunt. Dynamically the engine just cant deliver. Turbos are great for increasing torque, so run a turbo that allows the engine to breath well and really ramp onto boost when the std engine is singing. Its been a while since i have driven a std turbo RB20DET, forgetting when they boost for a second, when do they start to pull? My memory is in the early 4,00rpm range?!?!?!? But tend to die off at 6,000rpm. It would be very interesting to see a std turbo graph against something like mine

[LTHLRB]

yeah ok, BUT a turbo setup with a tight exhaust and a good amount of revs will work yes?

[abu]

My point is, a short stroke 2L six is never going to be king under 3,000rpm, so no point trying to size a turbo to get low end grunt. Dynamically the engine just cant deliver. Turbos are great for increasing torque, so run a turbo that allows the engine to breath well and really ramp onto boost when the std engine is singing. Its been a while since i have driven a std turbo RB20DET, forgetting when they boost for a second, when do they start to pull? My memory is in the early 4,00rpm range?!?!?!? But tend to die off at 6,000rpm. It would be very interesting to see a std turbo graph against something like mine

Well if you want to know what a standard turbo RB20 drives like feel free to come and take mine for a spin.. in return for a drive in yours, but you can drive! lol

They do generally die off around 5500-6000rpm and really struggle after that to get to red-line. Mine is fairly stock, just cat back exhaust and pod. Haven't put the rest of my stuff on do to waiting for the car to get through compliance.

Cant even think when they get to full boost, and I just drove it about an hours ago lol. No idea but generally start pulling fairly hard about 3,500pm + till about 5,500 - 6,000rpm.

Edited September 8, 2007 by abu

[abu]

come on man, u know the rb20 runs 6 cyls rather than 4 so that means SLIGHTLY quicker spool, also mixed with what the engine is built to do etc

a 3071r will be MORE responsive on a rb25det and rb20 rather than the sr20, lets say.. equiped with cams?

but personally i would do a 3071r with an external and .63 exhaust.. that would be pretty sweet.

Phil, whats the 3071r rated at HP wise, and when would you expect full boost on an RB20?

[Roy]

Tight exhaust as in small A/R? Yeh sure, but your talkign about flowing a lot of air through a hole the size of a 5c piece. You could end up with something that surges onto boost but then chokes and doesnt take any ignition as the engine is choked fuill of exhaust gases. Its a balancing act that i persoanlly fluked

[abu]

Anyone know about a Garret GT2876R? I believe its rated at about 450hp..

[LTHLRB]

abu: i think around 500hp? not too sure, just look up on the slide website or whatever.. its bigger than a gtrs i know that for sure.. as in response i would say something before 4,000rpm on full song? around 20psi boost

roy: yeah i know that, but obviously u want good response, means less overall power. You cant run a small turbo and want killer response and also want 450kw with a single.. but if its moderate power around 230 - 250kw with good response.. i would say a 3071r

[abu]

abu: i think around 500hp? not too sure, just look up on the slide website or whatever.. its bigger than a gtrs i know that for sure.. as in response i would say something before 4,000rpm on full song? around 20psi boost

roy: yeah i know that, but obviously u want good response, means less overall power. You cant run a small turbo and want killer response and also want 450kw with a single.. but if its moderate power around 230 - 250kw with good response.. i would say a 3071r

Full boost at 4,000rpm is alright, I will look into it.

Thanks Phil.

From my understanding if you want response, you will have to compromise a bit of top end, but if you want over-all power, you don't/cant have that response down low as the turbo is too large.

I think what Roy is saying is fk the response off because the engine is too small get get anything out of it down that low in the rev range. Instead, get a good balanced turbo that will get moving around 4,000rpm and above and will hold all the way till red line giving you good strong power.. but for that you compromise power within the 3,000rpm range and below.

Is that right Roy?

Edited September 8, 2007 by abu

[LTHLRB]

[Roy]

Well if you want to know what a standard turbo RB20 drives like feel free to come and take mine for a spin.. in return for a drive in yours, but you can drive! lol

They do generally die off around 5500-6000rpm and really struggle after that to get to red-line. Mine is fairly stock, just cat back exhaust and pod. Haven't put the rest of my stuff on do to waiting for the car to get through compliance.

Cant even think when they get to full boost, and I just drove it about an hours ago lol. No idea but generally start pulling fairly hard about 3,500pm + till about 5,500 - 6,000rpm.

Driving as many cars with aftermarket turbos as possible will only help you make a more informed decision. If you think a spin in my car will help give you a feel for what they go like...sure.

Rock up to the monthly SAU meeting and we can go for a spin. Next dyno day i will see if i can get my graph overlaid on a std setup. I guess im trading 25rwkws through the 3,000-3,5000range to make over 50kws more at 4,000rpm then onto 100rwkws more at 6,000rpm?!?!?!?!

[Interloper]

Hey

Yeah I am also a big fan of the GTRS. I have read so much positive feedback about this turbo, they seem perfect almost.

Everyone that I have talked to who is running a GTRS has said they are awesome, come to think of it, I don't think I have ever heard a negative.

I think there a bit cheaper $2,300 now too, but do you know what sort of power they are good for on an RB20?

They should be good for at least 240rwkw on the RB20. There's a guy on the forums that has made 270rwkw on an RB25.

The GTRS has to be some kind of evolution/step forward compared to the old HKS2530 & 2540. They wouldn't have stopped producing them otherwise..?

[abu]

Driving as many cars with aftermarket turbos as possible will only help you make a more informed decision. If you think a spin in my car will help give you a feel for what they go like...sure.

Rock up to the monthly SAU meeting and we can go for a spin. Next dyno day i will see if i can get my graph overlaid on a std setup. I guess im trading 25rwkws through the 3,000-3,5000range to make over 50kws more at 4,000rpm then onto 100rwkws more at 6,000rpm?!?!?!?!

Thanks Roy, appreciate it.

It just seems to make me more and more confused! The more different setups I go for a drive in the more I don't know what to get lol

2 cars that I went in that really stick in my mind were a R33 running a 2530 and a 180sx running a t04e.

180sx had 241rwkw with supporting mods, and when this things hit about 4,200rpm it was just insane!! You didn't really notice the lag nor did you mind it, because once that thing hit boost it was all over.

The R33 had a HKS2530 running on 18-19psi, not sure what ECU or anything as it must have pretty much came out of Japan like that. This thing was a response machine! If you put your foot down it was just gonnnnne!.. so quick no lag just straight power/boost on tap.

2 different cars, different engines and setups. 180sx more like a power machine, the R33 more built for response I'm guessing but both where awesome fun.

Hence my confusion

[abu]

Haven't really been in or driven any R32 with after market turbo come to think of it..

Mostly all SR20s and RB25s!..

[Roy]

My mate had an R33 with baby cams, Greddy inlet, Pfc and HKS 2530. It is ht ebest street car i have ever been in. Any gear at any rev it just pulled like a train. So much fun to drive., but oh so easy to go scary speeds on the street.

[wolverine]

come on man, u know the rb20 runs 6 cyls rather than 4 so that means SLIGHTLY quicker spool, also mixed with what the engine is built to do etc

a 3071r will be MORE responsive on a rb25det and rb20 rather than the sr20, lets say.. equiped with cams?

but personally i would do a 3071r with an external and .63 exhaust.. that would be pretty sweet.

"come on man", lol i'm coming on

think about the volume of each cylinder (SR20 and RB20) and each exhaust pulse that is generated. larger pulses excite turbines faster/easier.

[abu]

My mate had an R33 with baby cams, Greddy inlet, Pfc and HKS 2530. It is ht ebest street car i have ever been in. Any gear at any rev it just pulled like a train. So much fun to drive., but oh so easy to go scary speeds on the street.

They freaking move don't they!

They are the ultimate response machine once that HKS2530 is slapped on and spooling.

[wolverine]

the GT3071 depending on the turbine GT30 (either 56m or 60mm) and 71mm compressor is approx 450hp allowing some variance on turbine housing used and compressor trim.

the GT30R or GT3076 is usually 60mm turbine and 76mm compressor which will range around 500hp (again give or take).

the GT2876 is worth avoiding. (compressor too big for the turbine)

HKS GTRS is a GT2871 with a 53mm turbine (with HKS T3 housing and 71mm compressor (56 trim)(approx 400hp but seem to make a little more) and is borderline for compressor surge but as a bolt on they spool-up quickly on an RB25 and should be a good thing on an RB20 but the 2530 seems to meet your power goals and should be a little bit easier to spool up but a little less top end.

Edited September 8, 2007 by wolverine

[abu]

the GT3071 depending on the turbine GT30 (either 56m or 60mm) and 71mm compressor is approx 450hp allowing some variance on turbine housing used and compressor trim.

the GT30R or GT3076 is usually 60mm turbine and 76mm compressor which will range around 500hp (again give or take).

the GT2876 is worth avoiding. (compressor too big for the turbine)

HKS GTRS is a GT2871 with a 53mm turbine (with HKS T3 housing and 71mm compressor (56 trim) and is borderline for compressor surge but as a bolt on they spool-up quickly on an RB25 and should be a good thing on an RB20 but the 2530 seems to meet your power goals and should be a little bit easier to spool up but a little less top end.

Thanks heaps man, thats really useful.

Does anyone know if the size of a T25 flanged HKS2530 is different to T3 flanged HKS2530?

[wolverine]

buy the T3 flanged one.