Best Trade-off For Power/spool On Rb20

[Roy]

yes that is valid, except looking at torque curves vs rpm is just as good a comparison as road speed imo.

But who cares what rpm things happen. You want to know what road speed its happening. No point in a guy grabbing the same turbo setup as me and expecting my results if he has std diff ratio, R33 gearbox and 19" wheels. The rpm he makes the power may be similar, but the road speed will be way different, with my car actually making loads more power sooner and leaving him for dead from a rolling start at 80km/h, or from corner exit of a 90km/h corner.

You need to look at what road speed you are getting the job done. It often highlights that no matter how small and responsive your turbo, and compromised top end. You may still end up with crappy power delivery coming out of a corner at 90km/h. Its smarter to drop wheel size or increse wheel size, or change diff ratio so that you can make way more top end power and still have usable power at corner exits.

The original poster is talking about using the 20 for motorsports...so gearing and where your power hits the road is more important then looking at the motor in isolation.

Most already apprecaite the subtle difference, but sometimes is worth repeating

[NWR31]

i thought he was interested in comparing what happens at the crank with different turbo combinations on rb's, the road speed will just be a result of a bunch of other things that he might not want to change.

So basically I am looking for the best trade-off between quick spool and power output. I am just looking for turbo information, nothing else.

Edited July 7, 2008 by norwest_rumbler

[Roy]

Well i went to a public school and to this day still sniff a lot of glue. So ignore me

[robots]

So what final gear ratio, gearbox, tire size do you recommend Roy ?

Edited July 7, 2008 by robots

[SimonR32]

cant find the graph yet but this gives you some idea...

Car : R32 GTST

Engine : Rb20det

Turbo / Supercharger : GCG RB25 hi-flowed turbo (converted to ext gate)

Mods to Note : Zorst, cooler, mangament, injectors/pump , spitfire coils, etc

Rev Limit : 8200rpm

Diff Ratio : Not sure

Dyno : Hyperdrive DD

Peak Power : 300rwhp

3000 rpm = Sub 40rwhp

3500 rpm = Sub 80rwhp

4000 rpm = Sub 100rwhp

4500 rpm = 110rwhp

[SimonR32]

I had one on my RB20 which was bloody tired (popped a few weeks later, not turbo related) and it still made decent power and was quite responsive. I think the thing should've made more power if the engine wasn't on it's last legs too. But still, 220rwkw on 1.4bar, not too shabby.

I'd love to see your dyno sheet of it being a pig, because mine completely disagrees with that.

Just the usual mods, nothing special, just turned the boost up lots

Note: That's an RB25 turbo, not "standard" as the sheet indicates.

Boost starts ramping up 400rpm later and ramps up at the same rate. It started making more power than the stock RB25 turbo at 3600rpm and made full boost of 1.4bar (20psi) a smidge after that. 1bar came at around 3300-3400rpm.

lots of midrange timing would explain the engine popping a week later and the good response

[SimonR32]

http://www.skylinesaustralia.com/forums/in...st&id=49900

god bless the internet

[limpus]

Like these guys have mentioned...hks2510 is the way to go if maximum response is what you're after...or like troy said...see if there is a T3 flanged gtss...that would be awesome...my old 32 had a hks2535 making 237rwkw had a decent trade off between power/response...but for what you want something smaller like a 2510 is hard to ignore...

[discopotato03]

Hi Roy , T3 flanged GTSS is a new one on me but there's no physical reason why it couldn't be done .

Just so people know the RB26 and SR20 style HKS GTSS turbos are different .

Housings are different because RB26 style housings are unique to that application .

The two turbines are different GT28's , RB type 11 bladed 62T version , SR version 9 bladed 76T one .

Different compressors , RB26 type is a bit of a special 59.6mm 56T , SR type generic 60.1mm 60T GT type .

HKS do T3 flanged GT28BB turbine housings for GT2530's and these would bolt up to an SR type GTSS turbo .

They used this same housing and turbine on RB20/25 specific GT2335/2540/GTRS as well .

The old 2510 is just a 2530 with the 11 blade 62T turbine substituted , same compressor wheel .

The SR type GTSS uses the better 76T turbine with a smaller trim comp (60T vs 63T) so its slighty more biased towards the hot side than a 2510 .

IMO less exhaust manifold pressure and more ignition advance = better result .

Cheers A .

Still looking for SR20 type GTSS cartridge (CHRA) number . Dont think anyone knows ...

Also when I asked Gary about his GCG Hi Flow for the RB20 I think I remember him saying it used an RB20 rather than an RB25 turbine housing - that would make a difference in response .

Edited July 9, 2008 by discopotato03

[phat_man]

who has more information on the t518z turbo.

i also want the best trade off for response/torque (not just figures, but so i can feel it) and power (like everyone else) but i want around 230-250rwkw, if it means im going to lag from breakfast to asshole to get 250rwkw then idont want that much, but i would like at least 230rwkw. i want the car to feel that its pulling hard(usuable power) by 3k.

its a r32 gtst

from what i mentioned earlier would the smaller exhaust housing version of the t518z be the best option?