Jump to content
SAU Community

Recommended Posts

That is a massive difference.

I think 272s would kill the idle a little too much for my liking.

SK,

Do you think the 260s would be better than the 256/260 for my application? I think I will drop in a set of cams and keep the GT-RSs for now. If it doesn't work out, the cams won't be wasted with smaller turbines anyway.

I have attatched the GTRS graph from the HKS website. I would love to know what has been done to that engine, because it looks like the engine is making 1.8kg boost at about 5000RPM. I guess the Jap fuel helps because you can run heaps of timing on spoolup.

Is the R34 RB26 a bit better than the R33 version? Or is the extra torque on the R34 over the R33 just due to ECU mapping?

The R34 GTT RB25DET Neo has solid followers, so Tomei have 260 degree Poncams for them. The 256's are for the R33 GTST R25DET (non Neo) which has hydraulic followers.

As for the HKS dyno, I have yet to hear of anyone, anywhere in the world that has achieved that result. I don't know what HKS did on the engine dyno, but this is what I would do;

1. Run a highly oxygenated fuel with a high RON, like TurboMax (sold as HKS Drag Fuel in Japan) :idea:

2. Use a water to air intercooler with iced water :aroused:

3. Who cares about detonation, it only has to do one run

4. Don't worry about tuning for daily life, just screw everything up to the max.

5. Use a constant loss water cooling system (not a radiator) and maintain the perfect engine temp

6. No flywheel, alternator or water pump

7. Run the turbo inlet off the dyno room airconditioner outlet, with no restrictions

8. No exhaust, mufflers or restrictive pipe, straight off the tubo dumps into huge vacuum assited ducting

This would give me a "true" result, but hardly what I would call "real world". But maybe I am just more devious than HKS. :rolleyes:

The R34 GTT RB25DET Neo has solid followers, so Tomei have 260 degree Poncams for them.  The 256's are for the R33 GTST R25DET (non Neo) which has hydraulic followers.

As for the HKS dyno, I have yet to hear of anyone, anywhere in the world that has achieved that result.  I don't know what HKS did on the engine dyno, but this is what I would do;

1.  Run a highly oxygenated fuel with a high RON, like TurboMax (sold as HKS Drag Fuel in Japan) :idea:

2. Use a water to air intercooler with iced water :aroused:  

3. Who cares about detonation, it only has to do one run

4. Don't worry about tuning for daily life, just screw everything up to the max.

5. Use a constant loss water cooling system (not a radiator) and maintain the perfect engine temp

6. No flywheel, alternator or water pump

7. Run the turbo inlet off the dyno room airconditioner outlet, with no restrictions

8. No exhaust, mufflers or restrictive pipe, straight off the tubo dumps into huge vacuum assited ducting

This would give me a "true" result, but hardly what I would call "real world".  But maybe I am just more devious than HKS. :rolleyes:

Yeah...I see your point :D

Just a bit of an update, with more road tuning, I now reach 1.3 bar boost by about 5400RPM in third gear. The car feels much better to drive. If cams improve the midrange even slightly, the driveablility will be good enough for me.

The only thing is, I will definately need to fix my AFM issue first.

Mik,

im running standard BNR34 N1 bottom end and BNR34 N1 turbos in my 32. I also have trust 264 9.1mm camshafts and the car is making more power than your car and is making full boost by 4750 rpm. There is something funky going on.

TG

rev210: do you actually know of anyone that can source a C/F prop for an RB26?

LW.

These guys can do one for you.

http://www.ctgltd.co.uk/motorsport.php

Or these guys...(probably better since the Dollar conversion works better for us).

Ask them about a group buy discount.

http://www.acpt.com/

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Thanks guys,  Yeah I should at least have them dynoed, at least then I know what I've got as a starting point.  The springs on these are hard as rocks. I vaguely remember Russman saying he was going to sell the shocks to me with the rocks fitted, as he was keeping the softer springs for his new setup.  I didn't click at the time but of course that was to let me know the shock/spring wouldn't be matched.  I also remember pricing up new springs around 2014-15, but, house, money etc. it never happened. So that was another reason to have them rebuilt. I have rebuilt the forks on many motorcycles so I think I could handle the seals on these easily enough, but getting the valving right would be a rabbit hole I cbf exploring.  Duncan, interesting to hear RP was tuning these back then. I might give them a call.  In the mean time I have been busy fitting sway bars. The Whiteline rear sway bar I purchased 15 years ago finally got fitted, along with the Whiteline front bar that showed up last week. Just waiting on new links for the front sway bar to finish that off.  And my spare set of advan AVS VS5's should be back from the powder coaters in a Pearl White finish sometime this week, with a set of Hankook RS4's lined up for fitting.  And then I just have all the suspension bushes to do. A comprehensive kit is on the way... Lots to do before the Ararat hill climb. Cheers guys 🍻   
    • Nice car! I’m glad folks in the US have gotten past the FnF and are buying real cool cars like the 260RS I was with a bunch of mates in Portland about a year ago and spotted a green Stagea (just a regular 2.5T AWD) parked about 2 blocks away and they were like “a what?” So I made a bet with them for a round of beers and said “ok one of you run down there and tell me if the steering wheel is on the correct side” 5 mins later the American comes trudging back up the hill and goes “he’s right guys. Ok what beer do you want?”
    • Should replace OR drop the tank, give it's good clean. Might be worth replacing that entire fuel level/pump/cradle thing with this: https://frenchysperformancegarage.com/products/fpg-s13-180sx-r32gtst-single-pump-hanger-kit-billet-hat-6-v3-fpg-089?gQT=2  
    • Thank you so much for the help
    • Yes it is ATF. I quote @Duncan "it takes a good synthentic auto trans fluid like Castrol Transmax Z" It's not a diff. It's a transfer case. Totally different thing. Yes, fluid will come out the sender hole. No you do not really need to drain it. Just pull the old, quickly poke the new, clean up and top up. But realistically, you should probably take the opportunity to change it anyway.
×
×
  • Create New...