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simonr85
04-05-2009, 13:45
Had my car on the rollers on sat at protec motorsport in preston. You dont get a graph just a table of what bhp atw it makes per 1000rpm. Mine made 140bhp atw at 7000rpm with blueflame exhaust and decat, gunnerchip and k and n induction, what is 140 at the fly? I was told about 30% more so 182bhp if thats true, does that sound right? My mates standard ctr made 145atw at his redline

Brealbags
04-05-2009, 18:15
thats ambitious! :shock:

Jamie.
04-05-2009, 18:18
About 150 is claimed at the fly per Renault's offical figures.

However, imo, the F7's seem to make good power and actually put out their claimed figures as a minimum.

My mate had a belter of a valver engine and that was 160bhp with decat, air filter and chip.

summeh
04-05-2009, 18:34
Had my car on the rollers on sat at protec motorsport in preston. You dont get a graph just a table of what bhp atw it makes per 1000rpm. Mine made 140bhp atw at 7000rpm with blueflame exhaust and decat, gunnerchip and k and n induction, what is 140 at the fly? I was told about 30% more so 182bhp if thats true, does that sound right? My mates standard bread van made 145atw at his redline

30% is way to much. Nick Hill and others seem to suggest +20% for front wheel drive cars.

So 140bhp ATW will give you 168bhp at the flywheel. That's not a bad figure. I have a suggestion as to how you could improve it though (will pm you).

At the end of the day though you need to take these figures with a pinch of salt.

ThRaXaIR
04-05-2009, 21:54
does it involve a very special summeh chip by any chance?! :O ;)

simonr85
05-05-2009, 10:17
Had my car on the rollers on sat at protec motorsport in preston. You dont get a graph just a table of what bhp atw it makes per 1000rpm. Mine made 140bhp atw at 7000rpm with blueflame exhaust and decat, gunnerchip and k and n induction, what is 140 at the fly? I was told about 30% more so 182bhp if thats true, does that sound right? My mates standard bread van made 145atw at his redline

30% is way to much. Nick Hill and others seem to suggest +20% for front wheel drive cars.

So 140bhp ATW will give you 168bhp at the flywheel. That's not a bad figure. I have a suggestion as to how you could improve it though (will pm you).

At the end of the day though you need to take these figures with a pinch of salt.

so what power would my mates civic type r be producing at the fly??? his was 145atw so can imagine quite a few horses have escaped since then, he still gets left for shit by me too with an extra passenger and my old exhaust in the boot :D

richy
05-05-2009, 17:05
my hybrid made 145atw which equated to 175.5atf, this was at rstuning recently which supposedly read low compared to other places, btw mines cammed etc

J o n
05-05-2009, 17:12
guys, remember you cant compare different RR results... well, you can but it's completely pointless and proves absolutely nothing. For example my ITB'd engine made 177.9bhp @ the wheels, which was 200.0 @ the fly on the RR I use.

30% would mean it's over 230bhp... which is beyond optimistic

MAXIBOY
05-05-2009, 17:28
thing is its the atw figure thats counts..

transmission loss between 18 and 30 percent i've seen used..

but about 20/22 percent on a clio unless somethings wrong..

or did he do a coast down to check..

J o n
05-05-2009, 17:41
thing is its the atw figure thats counts..

transmission loss between 18 and 30 percent i've seen used..

but about 20/22 percent on a clio unless somethings wrong..

or did he do a coast down to check..

ATW is deffo what counts, but it's still pointless to compare to other RR results as they can still differ massively. With ITB's and 428 cams I made 203.8bhp ATW @ Ric Wood's, impossible for the mods.

Transmission losses also need to be measured as you say, which is why it makes me laugh when companies use RR's that don't measure losses correctly by using set values, certainly explains inconsistent results

col
05-05-2009, 18:58
Whats the saying......."Horse power sells cars.....Torque wins races!" :wink:

J o n
05-05-2009, 19:20
thats the one yup lol

although not technically true, but it's always a good one for debates with Honda owners :lol:

Smokey McPot
05-05-2009, 20:30
I would assume that transmission losses would also be related to the condition of the transmission you have.

Mostly seems like guess work to me. I'd be curious to see what 123 makes, but I can't help but think its all a bit pointless.

number1
06-05-2009, 17:59
mine was 141 atw and 169 atf, I think its Add 10% plus 10 bhp to the wheel figure to get flywheel figure for Front wheel drives,