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That video is impressive. Very keen to get mine onto the road again now

Thank you!

This is at a solid 17 psi boost, but the heat was SO bad on this trip and event. EASILY 80-90% humidity and track temp was likely 120 F. Yes...that hot.

When this car first cranks up in the mornings and just after coolant and oil temp come up it is INSANELY fast!!! I am REALLY liking the setup so far.

Also one of the HKS coilovers wouldn't adjust (broken nut on top I dunno), so I left them on 4 clicks from full soft (and I think they have 13 or 14 total clicks). Also broke a fluid-filled subframe bushing but that's OK I have new ones to go in soon.

I LOVE the NISMO front diff. After the 500 miles breakin you can't even tell it's there until you start pushing gas. Even on this surface (bumpy, not that nice of pavement) the diff really worked well. It pushed a tiny bit, but when heading straight even stabbing throttle from 6k the front just PULLS the car up. Very impressed for sure. Managed to beat the New Z06, New Z/28, Hellcats (tanks with HP), and many other purpose-built tube-chassis autox / race cars. Everyone was absolutely shocked at the GT-R's performance and honestly it will be much better.

All this on 255/40/17 hankook RS-3's.

  • Like 3
  • 2 weeks later...

Started experimenting with cam timing this weekend. I have the Tomei Poncam A's (small exhaust duration), and decided to try the arbitrary 2 deg advance on Intake and 4 deg retard on exhaust (basically closing the Lobe-separation angle) - NOTE these are CRANKSHAFT advance retard numbers.

Upon startup the car wouldn't idle and was clear that just these small changes made very large changes to the way the car ran. I had to crack the throttle body a good bit just to get my idle valve to be able to control the idle. It's also a lumpier / gurlglier idle than before. Makes sense as I moved my total LSA 6 degree closer. After resetting my base time I noticed the car was a bit snappier on extreme bottom end. Seems to make boost quicker and has a flatter powerband. Bad news is the STRONG topend pull I had from 6500 to 8k is gone...seems to have flattened that out because I lost my "VTEC YO!" feel. Not saying the car is slower on a pull, but it definitely made a difference on overall powerband. I believe I may have gone a bit past where I want to be. I will reset the intake cam back to 0 today and see if just 4 deg retard on the exhaust cam helps. I will also try leaving the LSA around 4 deg and moving both cams the same amount one direction (advanced for more bottom end) and the other (retard for more top). Also it should be noted that I saw more knock with cams set on a tightened LSA! interesting it followed most of the theories I've read about pretty much spot on.

On my setup, I wouldn't be surprised to see it like being advanced on both cams the same amount (stroker may like the valves to open sooner). I need to schedule dyno time, but the idea is that I will have a fuel map made for each setting and I should be able to just swap maps on the dyno as we change the cam settings.

Rather than go off topic in the Borg warner thread, I'll mention it here.

The stock knock sensors aren't the best design, and being old there's no way I would rely on them.

Look into changing them out for some Bosch sensors off something heaps newer! The stock thread is a 3/8bsp (weird hey) the so you can get a plug and drill and tap that m8 or something strange cos you are an American , and bolt the new sensor on.

  • Like 1

no sweat on butting in.

I'm saving this for later. Totally reflects what I found.

http://www.sau.com.au/forums/topic/342963-camshaft-for-rb26-with-good-response-and-idle/?p=5531968

  • 3 weeks later...

Ran the car in the quarter on 17 psi and total street trim (full weight)

Not bad at [email protected]

IT was extremely humid (100%) and about 90-85 deg F. Not much time between runs since I was late and not many cars there (was supposed to rain...just didn't hit the track).

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Yes I did...but I really need to get back to the dyno I've made so many changes. That was older injectors, different fuel setup (actually changed it again today) and then I played with cams for seemingly ever. I'm going to get back and check it again and find some dead spots.

But first I am actually going to install a water/meth injection setup so I can play with that on the dyno as well

This is true. Apparently our cars are slower and make more power but hookup better...half joke half serious.

Can't tell you why this setup doesn't put numbers down like others do. I expected it to have more mph than it does now.



If you guys have anything else I can try please let me know. I have checked a lot of stuff on this car but when I look at things like the latest motive DVD episode on YouTube where they run the piss out of his stock bottom 26 I see that I'm still hanging in there with pumpgas and street tune. I mean 120 isn't "slow" but not as fast as I expected. Maybe cutting squish pads hurt me?

I got only 12.1/115 in rwd with an Aussie 300awkws... so yeah factoring in your dynos reading a tad higher it seems ok.

All i can say is, turn up da boost! WMI will help with that. Did you decide on the kit, still going to try a 6 injector setup or just going for a more traditional one?

I guess my point is: with all the parts I have, good compression numbers, stroker motor, .5mm SS valves, ported head, etc I figured the car would be faster at 17-18 psi on this turbo. Perhaps the 3" exhaust, or smaller cams, or removed squish pads are hurting me?

Then again it was disgustingly hot and humid outside. So if this is as slow as it goes I am going to be OK with the numbers


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