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Discussion Starter #1 (Edited)
I just got my car back from the dyno today. Couple of things worth mentioning before the numbers.

(1) As the engine has only 1,000kms after the build up, Top Secret didn't take the power run beyond 8,000rpm (even though I wanted them to). Consequently, I only have the dyno results as at 8,000rpm (although the curve is clearly still going up). After I add more kms a second stage tuning session will occur.

(2) The dynoing was done on pump gas only. After all, this is my daily driver and everyday performance numbers are most important to me. When I start doing some drag racing (next season), the engine will be tuned for race gas with more boost. :smokin:

(3) The relevant environmental details are as follows:
Ambient Temp: 25 degrees C (intake temp was 27 degrees C)
Barometric Pressure: 1019 hPa
Fuel: 98 RON (pump gas)
Tyres: 275/35/18 (slipping a little on the rollers, unfortunately)
Air/Fuel ratio at 8,000rpm: 10.8:1 (in the interests of reliability)

RESULTS (at wheels):
Power @ 1.8 kg/cm2 (25.6 psi): 796.3 ps @ 8,000rpm
Torque @ 1.8 kg/cm2 (25.6 psi): 80.2 kgm @ 7,500rpm

Given the differing views on converting rear wheel dyno numbers into engine power estimates, I'll let each person make their own conclusion. ;)

How does it go? Well, the car almost drives like factory in terms of stop and go traffic, etc. When you put the hammer down, nothing exciting happens until after 5,500rpms. Then its just plain scary. Although I'm only running low boost at the moment (1.4 - 1.5 kg/cm2), I can see that it's going to take some time getting comfortable with this much power. The delivery is simply relentless in the upper rev range. :(

Cya O!

[Edited for boost conversion correction]
 

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That is a great result Gio!! You must be very happy with that!

Its very unfortunate the wheels were slipping. I take it the car was loaded with all the sandbags they have there? What about the complimentary mechanic on the engine?

Thats it....I'm coming down to see you ASAP:D
 

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lol well done man........ when do u expect peak power to hit???
whats the specs of it (CC, turbos, etc etc)
 

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Staggering!

and I thought I was happy at the 484 bhp at the hubs that Abbey mapped my car to yesterday. (at 1.4 bar, 25/10's).
 

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Congratulations hipo! Nagata-san has not let you down by the sounds of it :D

Looking forward to seeing those stage-2 results!

Cheers,

Dan
 

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Nice.

These results put a smile on my face and at 1.8bar,superb!!!!

Henry:)
 

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amazing

good on you hipo,
I bet that makes it an interesting drive:)
Gary
 

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Awesome

Hipo,

Thats cool :cool:
Congratulations on a fantastic machine.

Oh yeah - when are you taking us out in it ? :D
 

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Discussion Starter #12
Thanks very much for all the kind words. I'm definitely happy with the results and as usual Top Secret did a quality job. :D

DCD... Yes, apparently they had the obligatory mechanic in the boot and 1 in the engine, however, I found out that my tires aren't in real good condition (read uneven wear). Gotta change them.

Piggaz... peak power should be by 9,000rpm as I'm not running very aggressive cams. Basic spec of the engine is: 2.8ltr, twin 3037s, single throttle, 272 IN/EX cams, 1,000hp fuel system and supporting mods.

gary... interesting is one way to describe the drive. As you well know when you get up to these power levels simple decisions can have big implications - sideways across lanes in the first two gears. :(

Bean... absolutely no problems. Do you want to drive?

Cya O!
 

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Hipo,

let me just think for a minute....
hmmmmmmm
yes, I think I'd quite like to drive.

Are you going to stick with Neova's or change to something like the 540S ?

:D :D
 

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Discussion Starter #15
Cheers, SPOOLIN. :D

Bean... I think I am going to try the Yokohama AVS tires. I haven't researched a lot myself so I'm just going on other people's recommendations. Apparently they are good high speed tire.

Cya O!
 

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Hi hipogtr,

Awesome results, congratulation :) I am sure you are very happy.

I bet it is scary to drive :eek:

2 questions:

What is the max rev the motor can take?

Is that power figure at the rear wheels or at all 4 wheels?

Thank you for sharing your happiness with us :)

Enjoy the drive, I bet you will ;)

Jeff
 

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Discussion Starter #17
Thanks for the comments, Jeff.

At the moment I'm only reving to about 8,000 or so. The engine is built to take 9,500rpms, so I'll be shifting around 9,000rpms as the speed of the needle is fairly quick at that point.

With regards to the measured power, I always thought that it was at the rear wheels as I wasn't able to reconcile my numbers to those of others on this and other boards that had also done their power runs on a 4WD dyno. Apparently I was wrong. The Top Secret dyno is a 4WD dyno and when I asked the guys there they said the power runs are done in 4WD. Having witnessed some GT-Rs on the Top Secret dyno recently, I can confirm that it is operating in 4WD mode. Also, on the dyno print out, the parameter listing indicates if its set to 4WD or RWD or FWD.

Having said that, I'm still at a loss trying to compare my figures with others using different 4WD dynos. Maybe someone the board can offer an explanation? For example, in my case with 796.3ps measured to the wheels, the power to the engine is estimated at 892.7ps. This estimation is calculated automatically by the dyno software by measuring drag as the rollers spin down after a power run. However, that suggests that the loss from the driveline is only about 11%. Everybody else that has quoted driveline losses in a GT-R seems to use a larger number - however, if I did that it only makes the numbers larger which I don't think is necessarily the case. Someday I'll find the right answer to this, but for the time being all I can offer are the figures in front of me.

Cya O!
 

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hipogtr...dyno figures are always under discussion.... Trust me, your car is ridiculously fast and thats all you need to know!!:D ;)
 

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hipogtr..........thank you for the infos :)

All I am after is whether the figure was at 2 wheels or 4 wheels, you have answer my question.

800ps at all 4 wheels :eek: ............I am not so sure if I want to ride in your car now, I might get scare :eek: :p As I understand the drivetrain lost is quite a bit more from a 4WD dyno then a 2WD dyno. I have to make sure I don't drink any water before I get into your car :D

Jeff
 

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Lovely numbers!

I haven't been paying attention so forgive me, is this car in the UK or is it in Japan?

I must pay attention in class.
I must pay attention in class.
I must pay attention in class.
I must pay attention in class.
I must pay attention in class.
:D

EDIT
\/Cheers:) \/
 
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