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Discussion Starter · #1 ·
I thought I would post up my dyno result from a trip to The Racing Line, nr Halifax, today. I was dropping off my R33 GTR for a bit of fettling over the next few weeks. Matt kindly ran it up on their Dyno Dynamics rollers so we could have some sort of comparison after the mods go on.

Current spec:
95 BCNR33
Standard turbos and elbows
Custom decat exhaust, downpipes back
HKS SPF filters
Cusco catch tank
Apexi PFC + BCK (mapped to 1 bar)
Tomei pump
NGK iridium 8s

Mods planned:
Clutch - ?twin plate
GT2860R -7 turbos
Modified elbows
Tein Super Street suspension
760cc injectors
Oil cooler and relocation kit





As you can imagine I was pretty pleased with the results :D

My only question is, the torque peaks at 5500rpm roughly. Would this be expected for a car running a flat 1 bar of boost, or might there be some aftermarket cams in the engine? That torque curve mirrors how it feels to drive so I'm sure it's real. Power is still rising at 7500rpm when the limiter cuts in, which was again suprising.

I'll post further graphs once it's been modded and remapped.

:)
 

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The graphs dont come up, only white squares, red crosses. Would be interested to see what power that makes.

Tom
 

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Discussion Starter · #3 ·
Cheers Tom.

For some reason it won't let me edit my original post so try these images.

At the flywheel



At the wheels



I hope these now display...
 

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I'll make a comment, you got 2 HP more than I did :D at the same place and mine is stage 1 so it looks like our cars put out pretty much the same for the mods we have. I don't yet have a chip that is mapped (Mines VX Rom) but am looking at upgrading fairly soon: Garrett GT2860-5 turbo's, Greddy Emanage Ultimate piggyback ECU, 650cc injectors, Tomei fuel pump and adjustable FPR. What sort of power are you after?

MidNite :cool:
 

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Discussion Starter · #7 ·
MidNite

I'm after 450-500bhp, with a low boost threshold, and reasonable reliability. That's why I've gone the -7 route. I don't think the -5s are particularly laggy but I wouldn't be making the most of them at the boost I'll be looking to run. I think to run the -5s safely my engine would need a refresh, then I'd get talked into more mods like headwork etc.

Samuel, I think drivetrain loss was calculated from a coastdown, but I stand to be corrected.
 

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Simon,

You'll make that power easy with the mods you are getting. I know what you mean about the extra work though. I am having this done as I don't know what the turbo's in mine are and thought that if I had new turbo's in, I might as well have a few other safety mods done at the same time. Mine was set to run about 1.25 Bar when it came from Japan, I run it at about .9/1.0 now, but when I get the extra stuff in will run about 1.3/1.4. At least when I have it done I know/hope my engine won't go BANG :D

Have a look at this to get more of an idea of what I'm talking about Upgrading for safety more than power ?? - Skyline Owners Forum

MidNite :cool:
 

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Discussion Starter · #9 ·
MidNite

Have you done any calculations to assess flow etc at various boost for a standard RB26. I have and it makes quite interesting viewing.

For example, at 1.5 bar boost assuming 100% VE and IC efficiency the RB26 will flow around 60lb/min of air, therefore a theoretical max bhp of around 600 at this boost level.

BUT, neither VE or IC efficiency will be 100% so mass air flow will in reality be lower. I've calculated from datalogging that at 1bar of boost my standard R33 GTR IC is at least 90% efficient. From the dyno run and typical road data my NISMO AFMs flow 650 kg/hr each of mass airflow at 1 bar boost and AFR 11.5:1. From this data and the flywheel bhp you can calculate that my brake specific fuel consumption is 0.6 and VE at 7500rpm is 90.5%.

Now if I run 1.5 bar at 7500rpm with the GT2860R-7s (which they may not be able to do) and the figures calculated above then I will net around 490bhp ATF. Maybe a little more if the less restrictive turbos improve VE a bit.

See this site for all the relevant calculators and how-to's
Stealth 316 - Technical Information
 

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Simon,

I haven't done any of these calculations before but I have had a look at that site and there looks to be loads of info there. I didn't know how to read the flow charts before but I get it now, thanks for that. I will work out how much I should get with my mods.

MidNite :cool:
 
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