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.....Personally I think stock GTRs are too laggy as they are standard... 4000rpm is WAY too late for boost to kick in for a street driven car IMHO. So going for 2540s (bad idea) would reduce  boost threshold until about 5000rpm. Is that what you want???

For a street car you should be aiming for a fat, plump, even OBESE area under your power curve, starting from as low down in the rev range as you can get it.

Sounds like you need a V8 then!

Me personally, I find the non linear power delivery addictive.

Don't want to start the HKS25/40 debate again but I was on 1 bar of boost by 4,000 using these terbs prior to doing my big end bearing. Adjusting the cam timing gave a solid mid range punch with a similar shape to my std terbs (although obviously much higher!). I found them to be a solid street/track option.

With the present rebuild, I expect the head porting and the HKS exhaust manifold will ensure that this mid range bulge is retained. Hopefully have a power curve in a few weeks for comparison.

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flybye.jpg

* A tiny bit of artistic licence has been employed in the attached diagram :rofl:

that dyno graph is pure gold :D:):rofl::):rofl: but its exactly the sort of power curve an alarming number of people like seeing these days..... and its a shame, cause it would be a much nicer car if the power came on much much earlier. Peak power means nothing really, its just a way of saying my dicks bigger than yours..... if you want the perect street car its gotta have LOADS of power from about 3000rpm and up :):)

Sounds like you need a V8 then!

Me personally, I find the non linear power delivery addictive.

Don't want to start the HKS25/40 debate again but I was on 1 bar of boost by 4,000 using these terbs prior to doing my big end bearing.  Adjusting the cam timing gave a solid mid range punch with a similar shape to my std terbs (although obviously much higher!). I found them to be a solid street/track option.

With the present rebuild, I expect the head porting and the HKS exhaust manifold will ensure that this mid range bulge is retained.  Hopefully have a power curve in a few weeks for comparison.

Twin Turbo V8 = KING!!! :rofl::D:rofl:

Sounds like you've got a great setup! Whereabouts do you live? Up for a drive to Melbourne sometime later in the year? We're organising a dyno day for all GTR owners with low mounts upgrades (or power goals in the vicinity of 300-350awkw) so we can dyno them all on the same day, same dyno and stop all the misconceptions once and for all!!!

Should be a great day, I think I'll drive down, and truck the car back home :rofl:

Ok, they are just your normal N1s not your 34 N1s. The car is an actual N1 so whatever type of turbo they came with is what ive got, i dont really want to change anything that can't be reversed (Ie Bigger Turbos, i'm staying with the N1s, if i win lotto i might buy a 34 and use that to play around with some more).

Street driveability to me means able to drive through traffic without stalling/spinning the tyres, able to come on boost without the car trying to jump off the road etc.

Im with Merli and Marlin - i'm after good torque figures as well.

At the moment boost is coming on at around 4000 which i find is fairly laggy and 5000 would be ridiculous for what im after. I'm also putting on the ORC clutch which i understand smooths things out with the 4.8kg flywheel.

Merli - great idea, but logistics are a touch difficult!

I actually DO live in Bulgaria (I'm not taking the piss in my details). Car is being rebuilt in Perth atm with some serious internals to support the 25/40s and ensure a wide curve (i.e. extended rev range). The dyno work WILL be done on a DD unit in Shoot Out Mode, however. And, as stated, WILL be tuned for torque, not just peak power.

I actually DO live in Bulgaria (I'm not taking the piss in my details).  

:rofl::D:rofl:

Sorry mate, I thought you were just joking around with those location details!! :Oops:

That's a pity, because your car sounds like one of the most complete 2540 setups I've heard of :rofl: Would have been great to have you attend the day! :)

:werd:

Power under the curve >>>>>>>> Peak power dyno queens.

No, the reason FLYBYE lost wasn't due to no traction, it was due to a power curve that resembles* this:

flybye.jpg

* A tiny bit of artistic licence has been employed in the attached diagram :rofl:

was the dyno done in shootout mode?

140mph and 10.7 as a true streetcar is a great effort and better that all the PPL knocking on this thread so do better or shut up.
Corners Theo....... corners. It's not ALL straight lines mate!

:)

So 303rwkw... That would correllate quite well with jezzrrr's 285awkw... If anything, that would translate to LESS than 285awkw

Yet you run 128mph, and jezzrrr runs 118mph.

jezzrrr: Do you see now, why people think that your reading is a little optimistic? :(

Couple that to the fact that peak power means nothing... I just heard about a certain race between FLYBYE (making in excess of 400awkw) and a 270awkw WRX in a 600m standing start race at Bathurst (can't remember the event, I'm sure others will), and the WRX beat FLYBYE, as well as another GTR of Domenic Russo (Autostyle) lighting up the dyno with more than 400awkw :Oops:

Given that markr34gtr ran 11.9 with approx 305RWKW in his R34 GTR with 2530's NO I dont see why "people" would question the reading.

I am certainly not preoccuoied with dyno readings, its about driveability and response for me. NOT everycar that gets on the dyno that I go to turns out freak figures (quiet the opposite in fact), I just happen to have been very lucky with my 2 cars. Ive said it before - come to perth and come for a ride.

Looking forward to seeing your cars ressults down the 1/4, if you happen to finish it that is.

Looks like I touched a nerve ;)

There really wasn't any need to tell me to shut up, was there? Is that your level of maturity? Unable to have a discussion without lowering yourself to the vocabulary of a 12 year old cussing for the first time in the absence of his parents? :(

All I was saying, before you got butthurt, was that 285awkw and 118mph is slow, comparative to other GTR's terminal speed with similar power. Take it how you will.... as an adult or a little child. Your call.

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