Leadfoot

$70 just transferred to Dan's account (will not be processed by bank until Monday 8-Nov now though)

Count me in (for myself only). Thanks Andre.

Nope, the Greddy RB26 clear cover wont fit over variable inlet cam controller on the RB25. You will notice a bulge on both the left and right side of the RB25 cover. RB26 cover has a bulge on right side only. I bought the Greddy cover thinking I could heat the plastic and a make a second bulge. This would have worked okay on acrylic but turns out this is polycarbonate which tends to bubble badly. It could possibly be done using proper blow moulding equipment, however the shape is also completely wrong. I turns out the clear greddy cover is about an inch too short (leaves a gap at the bottom where dirt can get in). Also does not match profile of cams and leaves a gap at the top. All in all the GReddy cover is not worth the hassle of fitting. The good news is you can get a clear cover made exactly to fit the RB25 from PSI parts made by sniper racing. http://www.psiparts.com.au/front.asp?pid=8...33S%2DCCGC%2DPC I havent fitted it yet however I have had a good look at it. My only comments are that it is a bit more flimsy than the GReddy cover which is fairly strong. I would say the plastic is about half the thickness (say 3mm compared to 6mm). Given the cover is not subjected to any load I would say it should be okay. The surface finish of the RB25 cover is not quite as good as the Greddy cover either (but still acceptable). Greddy cover is high pressure injection moulded in a polished die. The RB25 cover looks to be blow moulded over a female mould.

Here in Perth Toyo Proxes T1R 235/45/R17 = $230ea Maybe cheaper over east. I previously ran Toyo Trampios 235/45/R17 and had some trouble with traction after upgrading to HKS2835ProS with 255rwkw. With the T1R's on the back I can now give it full stick in first and second with minimal if any wheelspin. I cant vouch for Proxes4 but they are only $10 to $20 cheaper at most. Trampios were a pretty good tyre to begin with but T1R's after definately better again. I am no longer getting the rear sliding out at Motorkahana's. Others are getting very good results with T1R's for hillclimbs and Targawest.

I would not rule out your EBC not to be the cause of the slow reponse. I have the Blitz i-color and it took me ages to get it set up right. Initially it took me days to figure out what I was doing but now I can get close to what I want in about an hour of solid road tuning. I gained a massive improvement in response by changing from single stage manual to 4 stage manual. If your using auto control or single stage manual control they are both very very lazy. If your are already using 4 stage manual then try and increase the duty of the sub 3000rpm stage and see what happens. If you are not using it in 4 stage manual control then you could easily be loosing 500 to 1000 rpm to full boost. An incorrectly setup EBC is evident by results of 0.8bar at 3000rpm and 1.0 bar at 3500rpm. If this is the case then 1.0 bar will still be achievable at 3000 rpm by correctly setting the duty cycle at lower rpm. It will take a process of iteration however I would start with the 1st stage from 0 - 3000 rpm, 2nd stage from 3000-4000, 3rd stage from 5000-6500 and 4th stage from 6500 - 7500rpm. You will then need to road tune each stage to find the right duty cycle for each. 4th gear of higher is best. Some adjustment of the rpms may also be needed to keep the boost curve as flat as possible. A good setup will actually give a small amount of overboost when the turbo first comes on boost. In the first stage I bypass nearly all the pressure at the wastegate (70% duty cycle) to prevent wastegate creep. This then quickly decreases down to 20% once the turbo is fully spooled. Faster response will also be achieved by increasing the spring tension on the actuators so that the EBC duty cycle is kept low at all engine revs. If the spring pressure is too low you will be getting waste gate creep costing you response regardless of EBD duty cycle. Since you have 2 turbos on the GTR some care would need to be taken that each actuator is set correctly. If one actuator opened before the other then all sorts of things could happen. For piece of mind it is quite easy to use a compressed air souce and pressure regulator to ensure the actuators are behaving equally and in unison. For a 15psi setting the actuators should be opening at around 12psi. The most stable boost control is obtained by taking the boost supply directly off the turbo(s) and not from the cool side of the intercooler. Whilst the idea of running cool air through the expensive solenoid sounds like a good idea it does not give the best result. In fact, auto mode on the IBC wont even learn if this setup configuration is used. Not on my single anyway. Pressure loss across the intercooler at higher rpms (pressure drop increases at higher flowrates) creates havoc on hot versus cold days and you will forever be fiddling with duty cycles.

Looks like it might melt a hole through when driving hard. Gets very hot even above the standard exhaust manifold heat shield. Clearance doesnt look like more than a few inches.

Yep, sounds like turbo bearings. Had same thing. At first the squeal only came in under boost. By the time I got home it was constant. The best way I could describe it would be the "woooooooo" sound made by a crowd at the fireworks. Even with turbo removed there was no real discernable play in the shaft. All turbine blades were attached. Turbo looked fine. Rotating the shaft by hand the bearings felt a bit rough however even that was difficult to tell. In the end, turbo replaced, no more noise.

Just for your reference: I did the HKS 2835 Pro S with poncams about 4 months ago. For reference here is the engine rpm versus gear at 1.0 bar boost (RB25DET R33 no other mods): 1st gear: 3900 rpm (additional dynamic lag is most noticable in this gear but also least important. Pulls a bit harder than stock with a big rush at the end) 2nd gear: 3500 rpm (pulls well from 3000 but really hits at 3500, can lose rear end traction with poor tyres. Better than stock everywhere.) 3rd gear: 3200 rpm (does not feel laggy at all at any speed. Very useable above 60 km/hr (EDIT - just verified) ) 4th gear: 3000 rpm (becomes a much more useable gear once the 2835 is in. Stock turbo did not have quite enough guts in 4th.) 5th gear: 2800 rpm The smoothest transient offboost to boost power delivery was obtained by setting up a 4 stage manual boost control to bring boost on as early as possible. That way power did not arrive late and in one big hit and 2nd gear rear wheel spin was sorted. I tend to agree that it might be money wasted, however money was not the object and I did not want to compromise but thats just me. The car is used on motorkana tracks with low speed 2nd gear corners and even with the poncams there is still a small amount of lag on corner exit of about one to two seconds. The other benefit of poncams is a lower dynamic compression ratio (more overlap) which may help improve engine longevity. To achieve your power goal the tuner will be able to run a more conservative tune or alternatively run lower boost levels, all of which may also help the motor last longer. The value of this, not sure, but thats how I justified it to myself !!

In a straight line: (r33 + GT30) > R34GTR On a track: R33 GTST < R34GTR The majority of time: R33+GT30 > R34 GTR Fun factor: R33 wins Status factor: GTR wins Choice comes down to individual needs and amount of cash in the bank. Also consider that you may be disappointed in the straightline acceleration of the GTR above 60km/hr where the R33 might be quicker.

Also installed Nismo 555's. Forum advice said use 0.71ms latency however it idled so rich it wasnt funny and I only just limped to the tuner. Would not come onto boost at all although the bigger turbo would have been 90% of the reason for that. My advice, if your idle sounds reasonable on 0.528ms then leave it there until you can do a dyno run. Boosting it before a dyno tune is not advisable. Every injector and motor setup is different. Latency and injector correction factors can only do so much and assume everything else is perfect.

latency is most likely incorrect you will need a full tune to correct this out To make removal of the injectors easier I would highly recommend using a short section of brass tubing to push the injector out from underneath rather than trying to pul/pry out from the top with a screwdriver/s. My o-rings must have been very dry or something and there was no physical way they would come out from the top. If you look closel from underneath the injector you will note that there is a very fine gap between the pintle outer shaft and the hole in the injector rail. Brass tube will fit in this gap and the injector can then be pushed directly out. If they are tight this is the only way they will come out without being damaged. Yeah, I used multigrips on the injector cap screws as well. They seemed to be "superglued" as well.

The tuner told me I need to fix a few things first before going back for a retune. They were getting spark breakdown under high load meaning they could not tune for over 360rwhp at around 1.0bar. Apparently each dyno run was also inconsistent to the previous making it hard to tune. The breakdown problem was the long life irridium plugs gapped at 1.0 mm. I was advised to go back to copper at 0.8mm. Once the plug electrode carbonises it will breakdown regards of being copper, platinum iridium or whatever. Gapping the iridiums to 0.8mm seems to have fixed the problem however it may now just be partially breaking down and causing knock. At 1.2bar I consistantly get knock up into the 80's. I also found I had a leaking PCV valve that was bypassing under boost back through the catch can (not measured by the air flow meter) causing it to lean out. That would have been the cause of the inconsistency. Another possibility is cheap chinese imitation Z32 air flow meters. Proper z32 airflow meters are packed in a yellow bosch box and has bosch written on it. It is also possible that the CAS alignment is out meaning that TDC could be a few degrees more advanced than what the PFC says. Once I have fixed all these items and pressure tested the intercooler and connecting hoses for leaks I will go back for a retune and see what happens.

Please check my post on your other thread. However, in brief, I have had exactly the same problem just recently and have good reason to believe it is due to the tune. I can repeatably induce knock in the 50 to 80 range without hitting rev limiter and have since reduced boost to 0.9 bar until this is sorted. I seem to need a slightly less aggressive tune than Xspeeds standard tune due to track use and a more aggressive driving style/vehicle usage. I will say this is probably my own fault for not advising Xspeed that the car is used at AHG for racing purposes. Also, Ignition was breaking down during the tune due to old plugs and 1.0mm gap even with splitfires. The tune was not 100% completely finished and needed another hour on the dyno. Nevertheless, the "random high knock" is real and repeatable and needs to be sorted before any more track use.

As NIB says I recommend you take it back and get some timing taken out of it. Probably best to note what rpm and conditions occured at the time of knock so they know where to take out the timing. Its funny you should have the same problem as me. Got mine tuned at X-speed the first time about a month ago and I have now have the exact same problem. I have recorded knock as high as 90 although it has spiked up to 70 probably about three times. 20 to 30 is the max I ever use to see on the old tune so it will definately be getting a retune. I am completely refraining from boosting anything over 0.9 bar at the moment. I will be taking the car back to have this sorted shortly. My guess is that the standard timing map used by Xspeed is probably a good compromise for general street driving and also gives a good result on the dyno. Usually what most customers want. A knock of 150 is regarded by the factory Nissan ECU is true detonation so a knock of 120 will need a retune. I get high knock during heavy acceleration when combined with wheel spin. Alternatively a high boost setting of 1.2 bar and around 5500 rpm will do it (knock of 50 or so). Was reluctant to repeat to prove conclusively. Just holding the throttle pinned in second gear and hitting the limiter was not enough to induce any knock over 20. Because I race at the AHG driving center the engine is encountering these types of conditions for a duration of 1 minute over the short-tight track layout. I have a Blitz IBC and I have tried all sorts of EBC settings such as gain and manual control which has not on its own (short of reducing boost to 0.9 bar) stopped the occurance of occasional high knock. I definately wont be competing again until I have had a retune. I am quite happy to sacrifice some top end power however to improve engine longevity if that is what is required. Unfortunately the ignition map has been hidden or I would post up some timing values for comparison. Basically I think road and track conditions are a lot more arduous than the steady ramping of a dyno roller and hence introduce dynamic transient conditions such a rapid acceleration or throttling on and off at maximum horsepower. The airflow meter probably doesnt react quick enough under these situations. I dont see this as Xspeeds fault as I did not advise them the car would be used for these types of activities. They also indicated (when picking up the car) that they would have tuned the car differently if I wanted a tune for "response" as compared to "horsepower". I guess I originally thought the standard map would suit both spirited and casual driving styles alike however may have been an oversight on my behalf. Advising the tuner of the required vehicle use may have avoided the need for a retune in my case. However, no harm seems to be done, and a lesson was learnt. Would be interested to here how you go and whether you get it sorted as this has caused me some concern also.

If you are saying the noise goes away when hot then it could be one of the gearbox bearings or input shaft bearings getting a bit worn. I have this problem also, however its only when the gearbox and the oil are cold. Cold mornings are the worst. After 1km down the street its gone. To test this just rev it up in neutral to 4000 rpm and if the noise does'nt appear (compared to in gear) then that's the problem. If it is a gearbox bearing I would just ignore it or maybe change the gearbox oil.