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  • 3 weeks later...
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Just got my car road tuned before the dyno with 740cc deatchwerks, in hind sight they might have been too big for my application (rb25 neo with 250kw highflow)

I went from a crappy magnaflow reg with 440cs to a stock rail, reg with the 740s and the car started stone cold first go, ironically it idled and low load was actually better with it untuned than it ever used to be, starts every time with no throttle.

Anyway got Pete at Nistune to do a road tune with them to make sure there weren't any major issues before the dyno, unfortunately due to their size we had to play with the k factor a fair bit to get enough resolution to get the AFRs above 10:1 in the top end, this in turn meant my idle and low load suffered a bit, though with lots of tweaking the latency and making sure the O2 was set up correctly got it as good as it was before, able to mantain stoich idle and get it up to 11.5:1 in the top end with enough resolution to still tweak it further.

The real test will be when we get it properly tuned on the dyno and see what sort of economy I get, it is fairly poor at the moment but the tune was just a "good enough" one before getting on the dyno.

Pete was very sceptical of them being able to work with the nistune and get the low load/idle/cold start working properly but when he saw how well they worked was quite surprised, even more so that they worked with no tweaking at all from my previous setup. Will report back when I get the full tune done and do some testing to see what fuel economy is like.

  • 2 weeks later...

Now has bilsteins and whiteline springs from one of sydneykids packages, got it 2nd hand with only 10,000kms on the, such an improvement over the frankenstein stuff I had before, rides better, less bouncing, stiffer and much more neutral handling now.

  • 2 weeks later...

Retuned tonight and made ~260kw on 16psi, we ran it up on 19psi but it would drop back down to 16psi anyway and didn't make that much more midrange so left it on 16 for a nice safe tune. Added some fuel after these curves which dropped it to about 255kw, peak torque from 3-7k, amazing powerband, incredible to drive, drives like a stock rb25det with 260kw!! Makes 5psi by 1800rpm and 10psi by 2800rpm

Added coolant temp fuel and ignition trim tables so it should be super safe if it gets hot in summer

afr

http://img135.imageshack.us/img135/959/img20120517221116.jpg

boost

http://img4.imageshack.us/img4/9011/img20120517221202.jpg

img20120517221144.jpg

Edited by Rolls

It's very interesting comparing our dyno curves Rolls. Despite the same peak power and our turbos both being highflows (albeit from different manufacturers), they are very different all over the place. Will post a graph later.

In fact, your graph doesn't even look like a turbo graph, it's much more linear looking. You have a fair bit more low end response than me, it gets on boost faster, but then I take over for the mid range and make my 258rwkw earlier on @ 5750rpm. Meanwhile, yours makes what is basically peak power ~500rpm later...but yours continues this all the way to redline as mine drops off. Be interesting to drive both and compare the feel, though it's a shame your engine is sitting in a different chassis lol.

I put it down to having a neo, with the old r33 rb25 it made peak power of ~240rwkw at 6250rpm on 18psi and then died off, neo head just seems to flow so much better that it makes more power on 16psi

Drives extremely linearly as well, barely even feels like a turbo

Edited by Rolls

eboost street, really neat device, had to add loads of correction to get it to hold flat boost, 25% more gain between 4 and 7k, wouldn't be able to get it flat without it.

Edited by Rolls

Yeah I think even a laggier turbo could make 200kw at 4000rpm because even a 300kw turbo is usually mostly on boost by 4k, it wouldn't be as linear or nice to drive on the street, for the track it would work though.

I really need some new tyres though, took it for a spin in the cold weather, even at 50% throttle with a full tank of petrol and people in the car second won't hook up, I think my diff opening up is a big contributor though. That will learn me for having 1 year old rock hard federals on there.

Edited by Rolls
  • 3 weeks later...
  • 2 months later...

Just wondering if you ever did get those Dw injectors flow tested locally?

No I didn't unfortunately, though they do come with pretty comprehensive flow tests from the factory, I can't see any reason why they would lie.

  • 3 weeks later...
  • 1 month later...

On grandfinal day/school holidays/long weekend I moved my car out of the garage at about 5am as I didn't want it to get boxed in when my house mate got home (she was working all night) anyway about 630am some f**kwits pulled up in a car, one guy jumped out smashed the rear windshield, kicked the side of the car in and keyed the whole right side, boot and roof down to the metal.

Had to claim on insurance which was unfortunately a $1500 excess, $6k of damage luckily it is insured for ~$11k so they are repairing it, full respray apart from the left hand side which was scratched when an old lady merged into me last year and they have already resprayed.

Kind of shitty to happen now as I didn't really want to fork out $1500, but it means I will have a completely resprayed car, hopefully get it back in a few weeks time.

  • 4 weeks later...

when you put the neo in with the older model gearbox what clutch and flywheel did you use? were you able to use the clutch and flywheel off the old 25?

As far as I know rb20/25/26 clutches and flywheels are all the same anyway, but I used my old rb20 clutch and flywheel as the neo motor was an auto with a flex plate.

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