GTRPSI

Firstly, before you do anything, check them for cracks, hot spots and the amount of wear on each face. Look at each face from inside where they contact the hub, is there a even mark all the way around or dots/marks pointing to high spots? Bearing packs tight with no play? Uneven wear or discoloration on any face being worn slightly more then another points to a sticking caliper. Once you have established where your issue is from, then machine the rotors on car, not off, its far more accurate. If your caliper is sticking, in most cases its a rusted piston on the skyline sumitomo calipers due to lack of bleeding through the years and water being absorbed by the brake fluid, best to replace the faulty piston (rather than polishing the old one) and use a new seal kit. Aftermarket seal kits such as TRW are fine and of high quality, stick with known kit brands if not going OEM. If your rotor is faulty there will be a obvious crack or casting defect running through it, as mentioned rotors deform for a reason.

Im a registered RDA agent, we sell thousands of sets of the dimple drilled and slotted rotors a year and a really high number to Skyline owners. Have a look here, there are a few TSB's that discuss it.....http://www.rdabrakes.com.au/page/technical.aspx We run them on all our cars, my sons had them glowing red hot (a automatic warranty rejection) that many times and never warped one, even in our GTR. Most common issues are warped hubs from tyre shops over tightening wheel nuts or dirt not cleaned off the hubs before fitting them so the rotor runs crooked, usually takes 3-5000Km to see the shudder in those cases. Most common Skyline issue has been a piston sticking in the caliper, seen around 4 of them with local workshops who called me to show me, once the calipers were rebuilt problem never returned. Some pads also like to cause disc thickness variation (we find bendix GCT pads the worst), again not a rotor issue. Can hardly blame the rotor for the above.... Here is a picture from my Falcon after testing for 60,000Km, you can see the blue heat marks from the amount of abuse they got, also note below that i had Apexi cross drilled rotors on the GTR and they all cracked from a few sessions at Winton, when we put the RDA rotors on the GTR and no more cracking, lap after lap, overheating them... You also have a warranty on them covering manufacturing defects, if there is a build fault with the rotors its covered.

Daz, give me a buzz when you have time to discuss your manifold. (if you have not purchased it yet) Or talk to the guy above me if you need one, if id known half what i saw late this week i would have grabbed a full race manifold from Geoff. I only hope i don't have the issues with my 6boost that ive heard first hand from a few people that have visited me this week of what they went through, they were 2 separate cases, both the same over boost issues......one returned for a refund after spending a packet on dynos following 6boosts advice trying to fix a crappy wastegate port fitment design, both sorted by changing to another brand of manifold. In their cases they were single gate designs, i hope my twin gate wont suffer from the same.......

Sure its not a sticking brake caliper or slider pins? Some pads on light brake pressure while moving make make a bit of a groan sound as the vibrate on the rotors, could be they are not releasing easily and partially on and draging.

Trent, you play with different turbo setups on your dyno a lot and have immense practical know how in that area, Daz made it clear he wants to stay Garrett (and he mentioned BW to me), what would you recommend to him? I can only suggest Precisions but he made it clear its a no go for him.....Garrett is really what hes after. Hell if i wanted around 650Kw at all 4 with response id be using the PT6870 but he wont hear of it.

Gate size and manifold.....we went twin 38mm which is larger than a single 50mm.....2268mm square area for twin 38 Vs 1963mm square area for a single 50mm gate. Bah, Garrett, go get yourself a PT6870

Daz, Daz, Daz.......700AwKw hey? Similar to my current build. One question you can put to the Bosnian (who im guessing will be doing all the work) Will it handle it without Darton sleeves and without a partial grout fill reliably? You did partially grout fill the block at minimum? In a nut shell your pushing the boundary of a reliable 26/30 with your current build, that does not mean it will fail, your just at the border. Did you anti friction coat your piston skirts? Massive side loading's and cylinder pressures at those power levels. Remember its not a 2JZ block or a N1 block either, if it was a 2JZ id say a very different story to what the bores can take. 700Kw and response? (Your joking right?) We are going PT7675...but im not chasing response. Maybe PT6870 at 650-700Kw on your current internals to keep costs down and reliability somewhat around. BTW how much exhaust porting was done to your head? Were at least the humps removed? You will need a good flowing head on the exhaust side. Me smells that he has corrupted you with a new drug called power addiction, tell him i said hes a big drug dealer and his customers are all becoming power Junkies, but i will add, all these engine builds and big power, so far no failures, maybe he sprinkles some magic fairy dust from Bosnia over his engines to make them last.

OK then, believe him and not me. Told you so....

The 28's have all retained the factory squirters, my 26/30 gets piston oiling Via holes in the Nitto con rods. The method of piston oiling makes no difference to the final outcome. Bearing clearances and oil weight would be more of a issue.....however the 28's and my 30 run the same bearing clearances and similar weight of oil, most of the 28's ran a multi grade 50 weight oil as they are regularly driven on the street, my 26/30 is setup to run a straight 50 weight oil (not multi grade) as its setup a little more strip than street.

That is the idea. 1.5mm is fine for normal driving and short bursts of RPM, as you know RB28's like to rev, revs=more oil going up=empty the sump faster which you dont want while holding it there in the upper RPM bracket.

Get a leak down tester (but fit your balancer on first) and do a leak down test so you can hear if and where the valves are bent before pulling stuff apart. It may be than only a few valves are bent, you can sort of get a indication of how bad it is before you pull the head off.

1.1mm is what im using on my 26/30 with Tomei pump. Most 28's that a well known Melbourne workshop builds also uses 1.1mm restrictors with Nitto and Tomei pumps. All were street builds with track/strip duties.

balls

Buy one, send it to china and get it copied in carbon, import them, make a packet!

Because it couldn't lay the power down? That seemed to be the only issue in the one i was in, till the owner fitted some ET Streets on it and sorted the suspension and stall converter. I will comment that he mentioned i was the only one who didn't scare in the car, to me it felt slow too, it didn't impress me. His drag slips said otherwise. It was the way it laid the power down, totally different to the way we are use to in a GTR.....

Its a simple thing, get cubes add boost. Ive been in a LS turbo conversion, stock motor, stock compression with a big single conversion and supporting fuel mods, bejeusus, 500+Rwkw on a E85 tune, it had a lot more in it but no forgies to risk it. And thats still pulling strong from the get go before the turbo even kicks in. The only let down is the Commonwhore chassis...

4.2 LSU 4.9 is being used by OEM manufacturers on car, the aftermarket wideband market is all using the 4.2 from what i saw. I couldn't find any aftermarket setups running the 4.9 when i looked. Key point is set it back as instructed and put a angle in to its fitting point to keep water out, its all in the instructions to get a long life out of it.

Removed the inlet hose, cut a thread into the passage, drilled a 1mm hole in a grub screw and loctited it in. I also pissed off the % gauge and used a normal 100Psi gauge. 95Psi reading when its set at 100Psi translates to 5% leak down If your compressor wont go to 100Psi, do the test at 50Psi and double the resulting pressure decrease to calculate the true percentage. So if you test at 50 PSI and the gauge reads 45Psi, your 5Psi drop means a 10% leak down.

And engine bay, including under the bonnet. Dont ask me how i know that......it was a bitch to clean off.....

Ive installed nolathane bushes with the grease supplied and they got noisy eventually. Have been told its a common issue with poly bushes.

Opinion of them Piggaz? Have you heard anything about them? 1400Nm.....but thats while rolling, i wonder what a 4wd launch would do to it with sticky rubber.....

Get a leak down tester and check it properly. DO NOT by a ebay leak down tester...i did and spent a whole evening modding it to work properly. They are suppose to have a 1mm orifice to work correctly, the ebay one didn't and i had to make one to get the right readings.

Well so far ive only learned we need more stroking, Head, and now fisting...sorry multiple fisting. Surprised no one has discussed better oiling.....because all that works gonna hurt real bad.

If your looking for a good wideband, look at the AEM fail safe one, ive just wired one up into one of our cars. Its a wide band that connects to AEM's gauge that also shows boost. its a 2 in one gauge. You can set up in the screen Via laptop for where you want Red, Orange and Green LED's to show up of A/F and they have a PC program you can run to set up at what A/R ratios you want alarms to go off at, the gauge can flash fast or slow and it has a out put alarm to trigger your ECU to pull timing (or whatever you need done when the alarm goes off). Also has the usual outputs to run the wideband into the ECU and around 2 hours of logging.

OP mentioned Bolt was already loose, ill bet key way and key is damaged. Get the best puller you can and have fun now. Dont let it go till the belt breaks......valves will meet pistons.....