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Discussion Starter · #1 ·
Hi guys what's the power difference between wheel horse power to engine horse power on the MY11 Gtr please, can you please give me a horse power figure not in percentages if possible. I did 3 power runs yesterday at a friends Dyno open day at MSL in Birmingham who just had the latest Four wheel drive rolling road installed and my car did 3 consecutive runs at 562.4 wheel horse power and 553.8lb foot of torque on a Litchfields stage one map with 102mm downpipes and K&N panel filters which I thought was bloody damn impressive. I've been told by a friend that the Gtr's lose about 24% through the transmission but I'm not sure if that's correct. Thank you chaps
 

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Discussion Starter · #3 ·
It was a Dyno Jet Dyno and I'll try to put a graph as well as the video I recorded on my phone
 

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Hi guys what's the power difference between wheel horse power to engine horse power on the MY11 Gtr please, can you please give me a horse power figure not in percentages if possible. I did 3 power runs yesterday at a friends Dyno open day at MSL in Birmingham who just had the latest Four wheel drive rolling road installed and my car did 3 consecutive runs at 562.4 wheel horse power and 553.8lb foot of torque on a Litchfields stage one map with 102mm downpipes and K&N panel filters which I thought was bloody damn impressive. I've been told by a friend that the Gtr's lose about 24% through the transmission but I'm not sure if that's correct. Thank you chaps
562.4 WHP @ 24% loss equates to 740 BHP at the fly - both outstanding and unbelievable. I guess you've been quoted the calculated values??? if so the WHP would have been 427.4.
 

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Discussion Starter · #5 · (Edited)
My car was fifth on the list to be done, they ran 3 mercedes c63 amg's and one Cls 6.3 amg before mine and they all made stock power give or take a bhp or two and then were remapped and were re-done and they increased by roughly 45 to 50hp
 

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Discussion Starter · #6 ·
562.4 WHP @ 24% loss equates to 740 BHP at the fly - both outstanding and unbelievable. I guess you've been quoted the calculated values??? if so the WHP would have been 427.4.
No their tuner who's been brought in from las Vegas specifically said that the figures are wheel horse power and he also said he roughly equates it 680-700.
 

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No their tuner who's been brought in from las Vegas specifically said that the figures are wheel horse power and he also said he roughly equates it 680-700.
OK, going for the 'normal' 19% transmission loss that I think is the 'calculated' value at SRR that would give you BHP of 694, the torque on the same basis would be 684.
Watch your rods as I read stock should be less than 650 for safety.

Who is the tuner you use as this appears to be anything but a standard Litchfield stage 1?
 

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Seems odd that the car is making almost exactly what you'd expect as engine bhp, but the place says it's at the wheels.

Personally I think they've made a mistake.

My MY11 Litchfield stage 2 car on it's "road map" made about 495 at the wheels on the hub dyno at Abbey Motorsport.
Which translated to around 590bhp at the engine.
 

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Discussion Starter · #9 ·
I'm no expert but I'm only going by what they said and what I saw on their screen and also what it showed on other cars
 

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I would think that is engine HP, i don't think stock turbo's would be able to flow enough to produce that kind of wheel hp unless your car has a crazy number of supporting mods and you are going for the fastest stock turbo records in a gtr. As Rich said, sounds bang on for a stage 1 crank hp figure which is very respectable.

H
 

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Transmission loss is NOT a % of the power and its just plain wrong to say that.

If your car makes 1000 hp at the flywheel with 24% loss it would lose 240 hp so 760 ATW

If your car makes 2000 hp at the flywheel with 24% loss it would lose 480 hp so 1520 ATW.

% just doesn't work, transmission losses do not go up with the power.


Dyno jet is renowned for reading high, 740 on stock turbos seems very high :)
 

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if a Litchfield stage 1 on a my11 is 590 hp then you have about 590 hp, so your looseing around 30 hp simple as that really.
 

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if a Litchfield stage 1 on a my11 is 590 hp then you have about 590 hp, so your looseing around 30 hp simple as that really.
I can't see the transmission losses on a GT-R being 30bhp.
I still think they've made a mistake at the Rolling Road.

My transmission losses were 75-100bhp on a similar car.
 

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I can't see the transmission losses on a GT-R being 30bhp.
I still think they've made a mistake at the Rolling Road.

My transmission losses were 75-100bhp on a similar car.
with a gtr a dynapack losses 50 hp hub to flywheel in reality, abbey ran a stock 09 made 435 hp hubs and there 485 at the flywheel so they loose 50hp simple as that imo.


a dyno dynamics will make a lot less at the wheels than a dynapack that's where the adding 20% comes in that then brings the figures in line.

dynojet read high so ive read so corrections will be small. the only way to confirm any power figure is by timing the car imo, I pulled 60 - 130 mph in 5.49 seconds in my gtr at 862 hp and that wasn't even in race mode ! that confirms its power being 0.1 seconds faster than a Veyron ;)
 

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with a gtr a dynapack losses 50 hp hub to flywheel in reality, abbey ran a stock 09 made 435 hp hubs and there 485 at the flywheel so they loose 50hp simple as that imo.
Interesting.
I didn't think any of the "claimed" 485bhp early GT-Rs actually made that.
That is a "simple as that" calculation made using an estimated figure that Nissan claim, not what the car was actually making.
I believe they made around 500bhp stock.

Either way Abbey did my MY11 on their hub dyno and the losses were 75-100bhp.
That's an actual car.
 

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The guy who built the dyno stated very clearly that the dyno gave wheel horse power only, have attached a picture of the graph as proof. The 3 stock mercs made stock power and after a map had the extra 50 horsepower the tuner claimed. It's a brand new dyno jet dyno.
 

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The guy who built the dyno stated very clearly that the dyno gave wheel horse power only, have attached a picture of the graph as proof. The 3 stock mercs made stock power and after a map had the extra 50 horsepower the tuner claimed. It's a brand new dyno jet dyno.
Cool, your car is making about 640-650 engine bhp then. :thumbsup:
Based on the transmission losses of my MY11.

So it's running stage 4 + downpipes. Or something like that.
 
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