Hanaldo

Gauge has been accurate up until now, last tank of petrol I got 280kms to a full tank. So that was about 18L per 100kms. This tank is going worse so far...

1. It feels heavy. 2. It sounds like you have a racing clutch, they do not like to be ridden. My Exedy Ceramic Racing clutch does the exact same thing if you ride it.

Ok thanks mate, I have been racking my brains trying to think of what else it could be other than a dodgy tune as Hyperdrive are supposed to be NIStune specialists I'll get on the phone to Andrew tomorrow then.

Already checked for fuel leaks, there are none. I will plug my laptop in and see if the closed loop is working, thanks mate.

Hey guys, Just got home from a dyno day at Autoworx with my club West Coast Cruisers, really not happy with my car... Long story short, it was converted to GTT using parts from a donor car about 2 months ago. At the time, KYP (the garage that did the conversion) had the car dynoed at Autoworx to make sure the AFR's were ok, car made 220rwhp @10psi with FMIC, EBC, stock exhaust except for the crappy mild steel 2.5" cat-back it had from when it was NA, stock non-turbo fuel pump, Apexi pod filter, and Splitfire coilpacks. They also replaced all the serviceable items, so new o2 sensor, new water pump, new timing belt, new gaskets, etc. Soon after getting it back from KYP I got a custom 3" straight-cut stainless steel cat-back exhaust (made by Kermit), 5" high-flow cat, and 3" bellmouth Tomei dump/front pipe. Then I installed a 550hp Walbro fuel pump, and made up a heatshield for my pod filter. 2 weeks ago I got a NIStune ecu installed and tuned by Andrew at Hyperdrive, one of SAUWA's sponsors and a very reputable tuner in WA... He set high boost on the EBC to 13.5psi, and the car made 243.0rwhp. Doesn't seem too flash, but Hyperdrives dyno is known to read about 20-30hp below, so Andrew told me my car was realistically making about 265-270rwhp. Since then the car has seemed to drive really well, it feels fast and it was a lot smoother than before it was tuned. But my fuel economy became shocking. I was getting about 280kms to a tank of fuel, driving on low boost and hardly ever hitting boost (I'm pretty relaxed, I drive it like it is a normal car). It is no better on high boost, and no better if I put my foot down all the time. Before the car was tuned I was getting about 360kms to a tank. Now today, I ran my car at Autoworx again and the result was 233.5rwhp. 10 less than I got at Hyperdrive which is meant to read low, and only 13 more than when it ran at Autoworx a couple of months earlier, despite all my modifications since then. The worst part is my fuel consumption. I filled my car up in the morning before heading to Autoworx, and when I got home my fuel gauge was sitting on the half way mark and I've only done 85kms... So I don't understand what the problem is... Bad tune is the only thing I can come up with. I have asked Andrew about it, but he said the only thing he can do is put it back on the dyno but I don't really want to pay for more dyno time and then find he still can't tell me what the problem is... Any suggestions? I will upload the two dyno charts for comparison in a sec... I tried to be as detailed as I could, but feel free to ask me anthing if I missed something, I'm all ears. Thanks guys, Martin.

What colour is your car?

Lol where would you put it? The R32's dash slopes down, the cluster would just be pointing straight at your feet... Unless you put it on top of the R32 cluster, which would look homo...

I think it's more likely to be cable flex, just adjust the cable. My car needed it as well, now it pop's really well.

I did understand that it needed different voltage, I just didn't understand how the voltage at the pump could be less than what was at the battery because I didn't know about the regulator

If I'm not mistaken, RB25DET Neo's also have solid lifters but my car does not have any ticking sounds. I've been around plenty of GTR's and never heard any ticking... On the other hand, my mate just got his R32 GTST back from an engine swap and the new RB25 has a noisy lifter that needs to be replaced, the car sounds like a truck at idle, very annoying sound.

+1. It's clearly a race, and the guy in front can't win if he is no longer on the road

Ticking could be a noisy lifter; does it sound like a diesel engine at idle but you can't hear it when you rev it? GTR bov's sound nothing like GTST bov's, but what you're hearing isn't dose.

Gotchya Yeh sounds like boost controller to me then, more common with bleed valves as Brezza said.

Wait... What? You're only hitting full boost at 6.5-7k? And your car revs higher than that for you to stay on throttle and notice that boost slowly drops?

What I've noticed with boost drop off when boost controllers are the problem, it tends to drop off towards redline. I would think that if the boost is dropping off immediately after hitting peak then it is because of the actuator. In any case, the best way of sorting it out is to rule things out from the cheapest solution up. I'd start by talking to your tuner, they may be able to tell you straight away what the problem is.

In a word (possibly two... hyphen anyway ), back-pressure.

Sounds like you want a high-flow... Speak to Stao at Hypergear

Yeh I get the same thing happening with my Greddy B-Spec II, the stock actuator can't hold that much boost.

Yeh shouldn't be much harder than wiring a sound system ^

Thanks guys, makes sense to me now I wasn't aware of the voltage regulator, which is why I couldn't understand how there would be such a high voltage drop. Unless you had a regulator, the voltage is always going to be the same. Will look into rewiring my pump now

Ahaa, that's what I was looking for. That regulator would be the reason that I couldn't find lol. But, who says that aftermarket fuel pumps require higher voltage? I can't find anything written by Walbro stating that they need a higher voltage, you would think that if it was going to make their pumps run better then they would make sure you knew about it. Thanks for the replies, they are answering my questions

I don't see why it would vary so much though ^ You shouldn't see a voltage drop of more than 1v from your battery. You would never see as high as 15v unless the regulator in your alternator is stuffed. Optimal charging is between 13.8v to 14.2v, so that is the max you would see at the pump. But even so, with the stock wiring you should not lose more than 1v, if that. So you should be getting between 12.8v to 14.2v at the pump, wouldn't matter what wiring you have. Maybe if we were talking about current it would make sense, but voltage is the same.

Man that was quick I don't understand that though, why would it not? Voltage drop on 2.5mm wire that is 3 maybe 4 meters long would be minimal. Resistance in series would reduce current flow, wouldn't do much to voltage. Telephone wire can flow 125v down the wire the size of a string, just low current. I don't see how there can be anything wrong with the wiring if the pump isn't blowing fuses?

Ok well I haven't been on the forums in a while, but I got this installed really easily. Only problem I had was my logic for soldering the new harness onto the wiring was wrong and it swapped the polarities, so initially the pump was sucking instead of pumping But I swapped the wires and sorted that out. Now I just wanted to ask why you need to rewire the pump. The guides I have found don't answer the question, they only tell you how to do it. I have left the stock wiring as is for now because I don't understand why you would need to rewire. Can someone elaborate?

Conversion nearly took that long