WalkyHR31

OK guys a bit of an update. Tried the new ignitor, spare CAS, fuel pressure OK at 40 psi right thur the rev range and under load. Drove it last week from my home in Maitland to SYD and miss really bad right now thru the rev range and nearly didn't make it. Engine was missing and felt like not getting fuel. Got to mates place (he runs an R33 GTST race car) and took front off to check timing and marks all lined up. So both of us scratching our heads. Just so happens by chance we were checking wiring and I had left the ignition on and went to check if plug was on CAS properly and when I touched it I heard the fuel pump prime. Every time I touched the plug or wiring the fuel pump would prime so obviously ignition was being turned on and off at this plug. Took off plug, peeled back insulation and low and behold one broken green wire but just enough insulation to keep it in contact until vibration or motor movement made it open circuit. then complete circuit again and so on. I guess after 30 years of heat and vibration this is bound to happen. Now this sensor controls fuel and ignition so hence the intermittent missing and fuel starvation. Fixed wire and now back to 400 WHP and 7500 RPM no problem! Drove back home yesterday and car going like a dream. So 6 months of pain for one tiny broken wire that I only found by chance. Hope this helps someone else chasing the dreaded RB miss!!

OK but have never any any reason to need that software as engine has performed perfectly since I built it 9 years ago. I have it dynoed every 2 years to check tune etc. Now about to build RB30/25 and am going to go with a Haltec so if I can't sort it out by trying different things that I have on hand then I will get the Haltec and hook it up and check all the logs etc. Going away now for 2 weeks so will get back into it when I return but I basically won't be driving it again until track season starts March next year. Thanks again for your help.

OK thanks but don't have any software for it. So I guess it will have to be suck it and see!

Z32 ECU with Nistune board. Sorry do not know how to log info. The only info I can get is via the ECU Talk display I have connected to the consult port. Maybe you could give me some pointers. Thanks

Yes both are alloy cases, so I will fit the spare and set the timing then if that doesn't fix it fit the new Ignitor. If that doesn't fix it then clean the MAF element and if that doesn't fix it then when I can get hold of the FP gauge check that (fuel pump is Walbro 255 fitted new 10 years ago but only done 20,000K's), so plenty to do. Thanks again.

OK thanks will try that. I also have a spare CAS out of a S2 RB25. Would that be worth trying? I assume S1 and S2 are the same.

I ran the gaps at 0.8 on my previous plugs for 9 years with no issues but can try 0.6 no problem. Yes they do have a separate ignitor and I just happen to have a new one in my box of tricks but completely forgot so thanks for the reminder. How do I do the exhaust gas test?...or do you mean just let it idle with the cap off and also give it a rev to see if any bubbles?

Hi Team, I have a built S1 RB25DET that was installed in my HR31 in 2014. Engine has been running perfectly for 9 years mainly doing track work so lots of high boost and RPM. Runs 20 psi. At a recent track day it started to miss once it got over 4500 and got worse as the revs increased. Could not get past 6000 in 2nd and 6500 in 3rd. Starts, idles and runs perfectly below 4500 under both light and heavy load. So changed the plugs that had been in it since it was installed with a new set of BCPR7ES gapped to 0.75, fitted a new Du-Luck R33 coil loom (original had broken plugs etc) and purchased another set of Splifire Coils to try. Every time I changed something I took it for a test run and then moved on to the next thing.Thought all that would do the trick but no, this afternoon took it for a run after changing the last 3 coils and same thing. I can check fuel pressure (have to borrow gauge) and voltages of the MAF and TPS via my ECU Talk readout, but thought I would see what you guys had to say. Thanks.

So what about the 4 control arm bushes. Where can I get a full set? Also, any reference to how to remove cradle and replace all these bushes? Thanks

Ok mate, thanks for all that info.

Guys, I need to replace the two rear cradle bushes and 4 control arm bushes on my HR31 Coupe. It is road reg'd but used mainly as a track car. I am not having much luck in finding replacements. I have contacted Whiteline and Nolathane and neither can supply any of them. Searched the internet with no luck. Not sure where to go from here. Anyone have a full set (or at least the two main cradle bushes) or able to point me in the right direction. I do all my own mechanical work but have not done this before so any detail on how to to actually change these would be appreciated. Thanks

Do you still have all these? If so, is harness and coils to suit S1 or S2 RB25DET (have S1 in my HR31 so don't know what BCNR represents). Looking for RB30 bearings and adj gears so if harness and coils are for S1 then can take all this. Thanks.

Its a bummer but a great track. I have been going there since it opened and love it, Currently run a HR31 Skyline with 2 mufflers due to receiving a nice letter from the EPA 2 years ago (noise complaint!). Still get the lovely RB sound inside and out but well under 95 db. Not necessary to have open exhausts or screamers. if we want to keep going there for great fun then this is a small price to pay.

Thanks Guys, appreciate the input and understand what I need to do. If I boofhead will reset timing with timing light.

OK thanks that all makes sense and I now understand the difference. Will reset voltage back to original value. Again makes sense so i'll try that on the dyno. Assume as cam is retarded CAS needs to be advanced the same amount to maintain correct static timing?

OK thanks for all that info, however, what you are saying is that the voltage is not that important at tuning but I constantly see posts here saying TPS voltage should be between 0.45 and 0.5 v. Re the ex cam gear are you saying that 3-5 degrees boofhead will improve turbo response, which I assume means boost will come on at lower RPM. Any idea by how much lower? I guess one tooth is about 8 degrees hence the need for a vernier gear.

OK thank you. WOT? I'll give it a try and can always reset back to original voltage. I think the voltage has changed as bit since it was tuned 8 years ago so that's why I reset it. Its a Z32 ECU with Nistune board. Yes understand re the adj cam gear and that I will need to check timing after adjusting. Mate David Zilm has a private Dyno Dynamics I can use.

Guys, a couple of things please TPS voltage has been at 0.36v for years (have ECU Talk readout) as could not get at it to adjust it and tuner said not a problem. Engine runs fine but now have front of engine apart and have reset to 0.44v closed and it reads 3.76v fully open. Is this about right? What is consequence of either low or high voltage when closed? Took opportunity to install adj ex cam gear. What is the go here? Currently run a TD06-25G, which is a bit laggy but once on full boost (20 psi) around 4000 RPM really gets going and holds boost through to 7800! Am led to understand retarding cam gives better turbo response as I would like it to come on a bit earlier. Is this correct? If so, approx how many degrees? Thanks

Yes I do in my HR31 with RB25 and R33 box and it is fantastic. Nice smooth, short shift and now never miss 2nd to 3trd with the heavier centreing springs. All for a round $200. Best investment I ever made as I use the car on the track and for roll racing where you need to do quick changes.

Hillclimb looks great. Much better than what we have here in NSW. Where is it located?

OK now I see why thanks. Yes, should be a bullet once 20 psi dialled in.

Hey mate, great vid. How do you get 380 RWHP on 14 psi? I am running an RB256DET with same RWHP but at 20 psi. Can you tell me what you have done to the engine as mine is pretty standard apart from forged internals, balance and bigger injectors with a Nistune board and LM TD06/25G turbo on a standard manifold. Thanks.

Yes prior to these I had a set of Harrop VL race coilovers with 12 kg springs and Bilstein shocks (non adjustable) revalved to suit. BC's are better with only 9Kg springs.

I have full set of BC's in my HR31 Skyline that I use for street and track and they are great. Select the right spring rate and you have 32 position shock adjustment to get the right setting for street and track. Great pricing too.

Yes that was option 1 but motor runs all stock gear - rods, oil pump, balancer, head, cams etc so wouldn't take too much more to reach breaking point! Anyway, already have 2 RB30 blocks, cranks, a head etc ready to go.