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Sydneykid

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Everything posted by Sydneykid

  1. Hi guys, the rub for me is quite simple, Munro's car does the numbers on the Tillbrook dyno and runs the times and speed commensurate with what the dyno says. Wilson's car does the numbers on the Willall dyno and runs the times and speed commensurate with what the dyno says. Theo's car does the numbers on the Croydon dyno and runs the times and speed commensurate with what the dyno says. Mark's car does does the numbers on the Sub Zero dyno and runs the times and speed commensurate with what the dyno says. David Lee's car does the numbers on the Ice dyno and runs the times and speed commensurate with what the dyno says. Bu5ter's car ran the numbers on the dyno and guess what............... That's Qld, NSW, Vic and SA Skylines all doing times and speed that look something like the cars are capable of according to their dyno results, not once but hundreds of times. Readers can draw your own conclusions:cheers:
  2. Easy peasy Duncan, just stick the trace wire in between the #1 spark plug and the coil, works a treat.
  3. Hi daveo, horsepower is torque multiplied by rpm. So the amount of torque is not really an issue, more where abouts in the power band it is. The problem with a 260 rwkw RB20 (more than enough to run 120 mph in an R32 GTST) is to do with how high in the rpm range the max torque is developed and for how long the max is available. This makes them very difficult to get off the line and hard to keep in power during the necessary gearchanges. Hope that helps:cheers:
  4. Like the standard ECU, the PFC O2 feedback is self learning.
  5. Hi guys, I don't know how to say this without sounding antagonistic, but I will try. If I remember rightly ND4SPD has more power on the dyno than Theo's GTR and it ran a 9, in fact lots and lots of 9's on Federal radials. But it was a different dyno, maybe that's the answer. Well I did try, I promise I did:angel:
  6. My experience has been that the problem with the RB20 isn't max power, you can easily get enough to run 120 mph. But the power band gets so narrow that they get really hard to get off the line and that makes 11's a bit of an ask. As Roy posted, bog and die or wheelspin city.
  7. 511 rhhp / 1.34 = 381 rhkw We get about 20 kw better on the hub dyno than on the roller dyno. So 381 rhkw - 20 kw = 361 rwkw (based on what I have seen)
  8. Or too lazy to connect up the rpm lead.
  9. Hi Boris, there is a great disparity in knowledge on any forum, this one is no different. You really have to be quite explicit (sorry but "etc" doesn't cut it when leaving a lot to the imagination of an unknown reader). To the questions at hand.............. The lightest GTR I have seen was 1320 kgs, lots of stuff was removed, but the sort of stuff you take out doesn't weigh much (except glass, that's heavy). The problem is the stuff you put in tends to be heavy stuff, eg; roll cage, oil cooler, extra sump capacity, larger intercooler, bigger brakes, larger wheels, bigger tyres, LSD, bigger turbo/turbos, 4" exhaust....you get the drift. I have taken at least 200 kgs out of ours, but it only weighs 50 kgs less than a standard one. On the bright side if I hadn't taken out the 200 kgs it would be 150 kgs heavier than standard. The next problem is weight distribution, our is around 68% front and 32% rear. The problem being most of the weight you remove affects the rear, stuff like rear seats, spare wheel, tool kit, NVH weights, rear wiper, HICAS..... But the weight you add ends up on the front, oil cooler, remote filter, larger intercooler, turbo/turbos, larger radiator..... I have a rule, if I have to have it, is there some way I can move it towards the rear (that means anywhere past the front wheels). And can I move to somewhere lower down, in circuit racing C of G is important too. Hope that helps:cheers:
  10. Viscous LSD's don't immediately lock when one wheel is spinning, they come on gradually as the viscous fluid heats up. You can only really test their action after you have been driving (and using the limited slip) for a while. ie; don't walk out in the morning jack the car up and expect to get a satisfactory result.
  11. Hi Magic1, well done you should be very pleased with the result. Some things for the other readers; There is no magic in ECU's, a 370 cc injector will flow 370 cc's at 36-38 psi with a light switch turning it on. Increasing the rail pressure by (50/36) 40% results in around a 15% increase in fuel flow (the hydraulics engineers will correct me if I am too far wrong), so a 370 cc injector will flow (370 + 15%) 425 cc's. You need to be careful as the injector solenoid and spring may not be able to close the injector against 50 psi. This can result in stuck open injectors, hydraulic lock on an engine is not pretty. If you increase the rail pressure to 50 psi, then you had better make sure you have a pump that can handle it, same for hoses and clamps. I have seen a pretty bad fire when the 40 psi rated fuel hoses spilt at 55 psi. Watch the pressure rating of the pump (eg; Bosch 044 is rated at 73.5 psi). So if you run 50 psi rail pressure that means you only have (73.5 - 50) 23.5 psi for boost. One of the things I have noticed with cars tuned for dyno comps is they rarely do 1/4 times commensurate with their power output. Regular readers will know I refer to "average power" (rather than "max power") as a superior indicator of performance (how fast a car really is). Some people prefer the terms mid range power or torque. In closing, I will quote from the Motec technical journal;
  12. Genberally this is a sign of it being tuned to rich for cold run, it fowls the plugs. Once its warm you give it few rpm and the plugs are cleaned and way it goes. Two soluitions, retune the cold run a/f ratios or stick in a slight hotter set of plugs. I would go for the retune personally. It is a bugger though, because you will have to leave your car at the tuners overnight so it is cold in the morning when he tunes it. Hope that helps:cheers:
  13. Hi Mike, dyno runs in 4th Gear are usual, as you said 1.1. Sometimes people use 3rd because they still have the 180 kph speed limiter, Power FC so you don't have that problem. I just guessed 3rd because of where the dyno graph cut off, I calculated the RPM using 3rd gear ratio. Since it is in 4th gear, it makes my previous posted rpm (guess) a bit high and just confirms my thoughts on restrictions. GTR's with your mods rev out way better than that, make good power to 7,250 rpm and don't drop off so much. There is something restricting the airflow, I am guessing the turbine/wastegate problem. Re; the wastegate, you actually have to repace the flap with a larger one as well as port it. The ones we get done have a flap that almost touches the sides of the chamber, they must be 4-5mm bigger in diameter. The flaps themselves are pretty cheap, just drill the rivet out, remove the standard flap and replace it with the larger one and a new rivet. The porting takes longer. Sorry have to go, I have a set of Bilsteins on the shock dyno:cheers:
  14. Hi Mike, am I right in assuming the dyno runs in 3rd gear? Pretty good result from the cam timimg, 25 rwkw at ~3,000 rpm and 20 rwkw max power. That's as good a result as I have seen. But, the max is still very low. There is some restriction in there stopping it from making the extra 50 rwkw. Without any better evidence, I'd be looking at the turbos. If the tubines truly are steel wheel but standard size, then that's a problem in making power. If the wastegates are truly standard, then that's a problem in controlling boost and making power. Some other suggestions; 1. What sort of knock levels are you seeing on the log? I try for less than 40, but I never get zero, ~25 seems average. If you are not seeing the occassional 40, then it could do with some more ignition timing. 2. What do the plugs look like? Mostly interested in the comparison accross the 6. 3. Have you done a leak down test? 4. What fuel? That's enough for now, this one has got my interest:cheers: PS: for a power comparison, we have a GTR with N1 spec turbos, great dumps and exhaust, adj cam timing (std cams), Power FC and it makes 275 rwkw at 1.2 bar.
  15. As I said above, just over 6,000 rpm is normal for an RB20 with standard cams.
  16. Was the dyno run in 4th gear? If so the graph stops at ~6,150 rpm, I hate it when they stop the graph, I like to see what happens all the way up to the rev limit. It is hard to tell where to change gear with a graph like that. Standard cams usually make max power at just over 6,000 rpm, so it looks quite normal. The reason it feels OK on the road is because it makes 5 psi at ~3,750 rpm and 10 psi at ~4,250 rpm. That's pretty good, a little bit of camshaft timing and some more lift would bring that down a few hundred RPM. If the dyno run is in 3rd gear......well you have some work to do.
  17. Hi Mike, a few suggestions follow; * A/F ratios need to be 12 to 1, 12.5 is better for power but 12 is safer. *Try opening up the lobe centres first, +2 Inlet and -4 exhaust and see what happens. Adjust the CAS to get the static timing back where it is now. You should be able to run more timing than you currently have, but watch the knock levels. *The boost creeep is a sign of mismatched turbine and compressor, I am concerned with "steel wheeled GTR turboes with larger comp wheel only". The turbine upgrade needs to be slightly larger in proportion to the turbine. That will cause boost creep if it is not increased and cost some power at higher airflows (RPM). *Did you get the wastegate increased in size as well? That will cause boost creep if it is not increased and cost some power at higher airflows (RPM). *The standard dumps are not your friend, but I don't think they are the limiting factor at the moment. But if you have to remove the turbos to fix the turbine and/or wastegate sizing then I would be changing them. *I assume it's cat free? I have seen a GTR that couldn't make 200 rwkw with a long list of mods, high flow cat and it made 260 rwkw. It had boost creep as well. *The AFM's getting to 5V at less than 200 rwkw is most unusual. That indicates the air is getting in, but not out. Can you measure the boost before and after the intercooler? Say straight out of the turbos and at the plenum? That will tell you if you have a restriction there. Unlikely but worht checking. *I would be looking at 16-17 psi of boost, if the flow job on the turbos is good they will do that nicely. *What ECU are you using? *Which Tomei cams did you choose? That's probably enough to keep you busy, let me know how it goes:cheers:
  18. My own 1990 R32 GTST weighs 1,240 kgs, 1/3 tank without driver. It has; No aircon No spare wheel No tools No HICAS No stereo or speakers No Rear seats or seat belts GTR Bonnett, front bar, skirts, rear spoilers GTR Intercooler (Roy knows it well) Oil cooler & remote filter Speedy Hollow Type R's 17 X 8's with 245/45/17 A032R's (not light weight) OMP driver seat (not a light one) with 6 point harness Jamex steering wheel & gear knob Big adj stabiliser bars (much heavier than standard) The Stagea weighs 1658 kgs, no fuel and without driver, so I no complain about about GTR's being heavy. :birdie:
  19. Yes and no you need an adaptor.
  20. What I do to check shocks; 1. Look at the shaft for signs of wear, scratches, hardening worn off etc 2. Check the seals to see if they are leaking, there will be oil around if they are 3. Shocks never wear exactly the same, so take the pair and compress them both. Make sure they both compress and rebound at the same rate. Try a couiple of settings if they are adjustable. I they pass all 3 tests chances are they are OK. But the only real test is to stick them on the shock dyno and do a dampening graph. Hope that helps:cheers:
  21. The change in rolling diameter would be greater due to tyre wear, which the ATTESSA handles easily. Take a front and rear wheel off and measure the circumfrance if you are worried, I will bet it's not as much as 8mm of tread depth.
  22. Personally I think you are much worse off. Firstly you have made the wires very easy to get to, just find the turbo timer and it's ready for a quick hot wire. Secondly you have identified the right wires for the thief to use, otherwise he would have to search through the wiring harness for the correct ones. Both the handbrake and speed sensor are conected to the TT, when the thief hot wires it he obviously removes the handbrake and speedo connections. So that is no barrier. The alarm can not cut ignition/fuel while the TT is running, if you program a built in delay into the ignition/fuel cut your car will be 2 suburbs away by the time the alarm stops it. Plenty of time in a nice quiet place to disconnect the alarm. Regardless, you are cooling down the turbo, and even that is debateable, but what about the brakes gearbox, diff etc. Much better to do another lap of the block and cool the whole lot down with airflow. My 20 cents worth:cheers:
  23. Personally I have never been able to get over 180 rwkw on the standard 270 cc injectors and that is with an adjustable fuel pressure regulator and a GTR fuel pump. I have 550 cc S5RX7T injectors in mine and Roy has GTR 444 cc injectors in his, if I remember rightly. Hope that helps:cheers:
  24. They are testing it the wrong way, what they are doing is connecting the positive from the multimeter to pin 7 and the negative from the multimeter to earth. This means they are measuring the voltage between earth (ECU) and earth (battery), obviously they will get no reading. What they should be doing is connecting the positive from the multimeter to positive (battery) and the negative from the multimeter to pin 7. They will get a signal then. Hope that helps
  25. I have no idea what the standard settings are but this is what mine will be set at. Front toe = zero Rear toe = zero Front camber = 1 degree negative Front caster = as much as I can get, but I know it won't be enough I will run a little more caster on the left (~0.25 degree) to stop the drift due to road camber. Rear camber = 0.5 degree negative Hope that helps:cheers:
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