Torques

OK, Thanks again ... that kinda limits the options. i checked on the price for used GTT calipers and they're too expensive to justify going the 310mm route. So what's left is Unique Auto Sports http://www.uniqueautosports.com.au/Parts-Shop/stage-1-brake-upgrade-kit-642.aspx or just getting the standard rotors ...

Hmmm OK ... thanks. I have 17'' GTR rims, so my options might be limited. From 294 to 310mm is not really a huge step, so cost wise I might have to explorer this. I will have to buy new rotors anyhow, and price wise they don't differ a lot between GTST GTT or GTR, If all fails possibly a set of new rotors, pads, and braided lines will help as well.

Thanks for the replies, I will have to check with the manufacturer about the required clearance and other work possibly to be done to fit this. With brakes I will make no compromises, so it has to be a solid solution/adapters. Too much at stake here. Also I need to find out about the origin of the rotors since I don't want to be stuck with 'special rotors' I can not buy on the free market. The 324mm solution seems not to be that favourable then? If all fails braided lines + new fluid + new rotors/pads might do the trick. Cheers ..

I will need new front rotors for my GTST and came across this kit: http://db-power.co.uk/products-page/front-big-brake-kits/345mm-big-brake-kit/ They seem to be using the OEM calipers on an adapter. So only the leverage increases not the surface area of the pads or brake pad pressure. I don't know where their rotors come from either, so a bit of an unknown. The alternative is buying known good standard rotors for about 70% of the price of this kit. Any thoughts on this appreciated.

I fitted this on a SPEC2, the REO bar had to be slightly cut

Interesting, was there any improvement or slightly more lag with the OP6?

Hi, Yes, always difficult to compare. Especially since Stao uses a hub dyno which gives different results to roller dynos. Also ramp rate etc. Still my figure of 220RKW is in line what most folks report here. Just my five cents .. Cheers ..

My logs showed about 70% duty cycle at around 220RKW. . As said it also depends on AF ratio. I had some ignition cut at 220RKW, but only when flooring it hard, (fuel / ignition cut might be different to what some people call limp mode)

Before the injectors max out the standard ECU will go into Fuel/Ignition cut. 220RKW is about 70% of injector duty depending on A/F ratio.

What's the difference between green and red line in the boost graph? And how would the boost graph change on P98?

Mixed up the dynos .. here's the boost graph

The standard turbo is hard to beat if you want that responsive feel. I had that standard turbo running at 1bar for a while until I went to the drag strip and to turbine wheel gave up. I bought a hybrid afterwards and was initially disappointed about the added lag. The factory turbo made about 1 bar / 14,4 PSI at 3000 rpm and .5 bar at 2500rpm. On the other had my hybrid lags the OEM turbo by about 600rpm with more upward potential and real fun from there on. Usable torque is from 3000rpm with no complaints from the engine department. Did you say what kind of boost you want to run? I personally would go for one of the smaller HKS ball bearing turbos. Or just get someone to rebuild the OEM turbo with billet wheels. I have attached one of my old dynos with the (over)boost curve of the standard turbo. It might help you decide on your purchases. . .

Hi, Sounds interesting .. have you got dynos? Cheers

Yes, already written off the HKS. Not worth it judging from you replies. Which Hypergear did you go for?

Just found this ..

Hello, I was hoping that the bridge between low lag and high power could be drawn easier these days. So billet wheels and ball bearing would be of my interest. All things being equal the HKS is a bit aged now and is 'only' rated at about 410HP (CRANK) or so. Back in the day that that was good power. I would need to do more research on available turbo options and how well they spool up on RB25. Making huge power is no so difficult but I need my car to be torque rich and responsive. My current benchmark is 1 bar (14.4PSI) at 3500 RPM and the new turbo should be in that region while holding 16-18PSI at 6500RPM. I once did the maths for this leading to the required compressor map. I will revisit Hypergears turbos as well .. Stao has many options available.

@89CAL -> That must have been a disappointment. Especially after investing quite a bit of $$. Would you have dynos of the HKS vs / and the Hypergear? Does the HG introduce more lag ? (it should) What is your current power? My turbo make 14.4 PSI (1BAR) at 3500 rpm. That's the benchmark I compare against for spoolup.

How happy are you with Hyper-Gear? Spoolup should be somewhat worse compared to the HKS. Here the PRO-S making 320KW on E85 http://www.skylinesaustralia.com/forums/topic/412682-300-rwkw-gtst-top-shelf-parts-only-price-drop-for-members/?hl=hks+pro

Thanks, GT30 would mean high mount / ext gate then ...(?) Would need to do some research on that I guess. If the KAI would do 280KW+ that would be enough for me but I think it is rated at about 400HP? Making less power than I have is not really an option

Would you have any dynos? (HP/Torque/Boost) And were you happy with the KAI, or did you move on?

Hello, Was your Turbo the HKS Pro S? Mine is just a Hybrid rated at 380HP. If I set it to say 14PSI target the boost curve would be more linear I guess I am just asking too much from a small turbo. I could double check if the gate opens too early but have no high hopes. Otherwise I see no restricting factors. Blitz FMIC HKS DUMP Tomei 4'' downpipe / Pon Cams HKS 3'5 exhaust

It's 252RKW (301KW crank) @ 6300 @ .9 BAR /13PSI In the attached file you can see how boost creeps out. My target pressure was 18PSI

Haha .. yeah, me too. Avoiding the spike strips in Need For Speed gave good practice

Thanks, I did the research and I think run flats are not for me, especially since I go to the drag strip from time to time. Their side wall must be very rigid ..

Thanks for your help, I made my decision and ordered 245/45/17 .. It gives me the right look and I guess I got it 90% right with that. I think it also comes down to person taste and what you do with your car. As said the GTR comes with these tyres and they fit without too much drama. Will report back when the new tyres are fitted. For a 225/40 tyre the right rim size is 7.5 to 9. It would look pretty stretched on a 9'' though. http://www.carbibles.com/tyre_bible_pg4.html