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Discussion Starter · #1 ·
alright everyone!!! my car is 520bhp at the wheels i have finished rebuilding it there is a few other mods what i want to do to the engine but this is up to now, what would it be at the flywheel every one works it out different!!!!!!??? what is the loss really through the transmission what percent does everyone use?? i have been told and seen what people have put its 15% or 24-25%, or 30% and i have even seen 34% being used so what is it?
what bhp is my car at the flywheel ??:)
 

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Discussion Starter · #3 ·
High Octane said:
multiply by 1.28 and theres your answer

666 bhp cool the devil..!! lol

any one else use different or is that about right like to hear what you all say
cheers mate
 

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520bhp atw thats no slouch! personaly i'd say 15% is about right. my car makes 461 atw that would make about 530 fly

mutiplying it by 1.28 would mean it prouduced 590 fly! i wish!:thumbsup:
 

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hi

ive heard one dopes before say (and im not naming who he is cause hes on here) that its a well known fact that gtr's loose 70 horsepower threw there drive train and thats it. they way ive been shown was said to me by a top tuner in japan and also by gary from gt art!
 

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I don't really understand why the power loss should always be a % of the flywheel power.
Of course the % of power loss can be measured in a particular case, but the difference of power between the flywheel and the wheels should always be the same in a particular car, and could be different if you use ie lightweight transmission parts like flywheels, propshaft, wheels etc.

If you measure a difference of 40 bhp in a standard GTR between flywheel power and at the wheels power, with a 280bhp engine, there should always be a 40 bhp difference if you are using a 600bhp engine.
 

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From a dyno at the hubs the figure is 70 bhp more.
so Lemon made 300 ath so is 370 at the fly.

****
 

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Maxi, Thats exactly what I was going to post, How can it be a percentage ? that means at 10% on 300bhp the box uses 30 and with 1000bhp it now uses 100!
 

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he may have a point though if you think you can walk through water without much dificulty but its bloody hard to run, think of all the fluid in the transfer boxes and diffs etc, the quicker it goes the more resistance there will be.
(dont know if im right or not its just what i thought up lol)
 

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But surely it offers the same resistance at the same revs IE 1000 to 7000 so even if you double the power you dont allways increase the speed that the engine (and box) turns at.... I agree that drag must increase with speed though.
 

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hi

70 horsepower loss my ****, its SOOOOOooooo much more than that!! why is it the veilside r34gtr made 1017bhp at the hubs and 1350bhp at the flywheel so!!!!! sumo power made 690bhp at the wheels and over 900bhp at the flywheel!!! the list is endless!!! a gtr loses way more than 70 horsepower threw its tranny and im suprised people on here think differently
 

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Has anyone actually checked and compared flywheel and RW hp by removing the engine and using an engine dyno ? from what you say high octane i wonder if the drag on the box increases with the extra load.... Is it also possible that these crank figures are estimates based on the hub/rw figures ?

with a 300bhp loss that gearbox must get extremely hot
 

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Are we talking 'at wheels' or 'at hubs' here and 4 wheels or 2?

I don't buy the fixed loss. Here's why. Start rubbing your hands together and slowly speed them up. Compare that with suddenly speeding them up.

If the transmission absorbed the same power at 300bhp as 600bhp, you wouldn't need uprated transmissions. The same force acting to brake the gearbox is expending useful energy.
 

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High Octane said:
70 horsepower loss my ****, its SOOOOOooooo much more than that!! why is it the veilside r34gtr made 1017bhp at the hubs and 1350bhp at the flywheel so!!!!! sumo power made 690bhp at the wheels and over 900bhp at the flywheel!!! the list is endless!!! a gtr loses way more than 70 horsepower threw its tranny and im suprised people on here think differently

Ahh cool then the Lemon is a 1000 bhp cool. Not:clap: :clap:

****
 
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