Recently dyno'ed my car before the new egine is fitted and the data was given to me as "@ the wheels", what is the conversion factor used on a mini to estimate flywheel hp ?

Hope that make sense ?

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1964 Grp Nb Cooper S
1976 911 3.6 Circuit Car
1969 911T Grp Sb Historic Racer
2009 LC200 V8 TDI.... 660nm..
2011 Golf VI, TSI

Is your car blue?

Yep, that her in the picture !!!!!.

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1964 Grp Nb Cooper S
1976 911 3.6 Circuit Car
1969 911T Grp Sb Historic Racer
2009 LC200 V8 TDI.... 660nm..
2011 Golf VI, TSI

at the wheels to flywheel depends on diff ratio and box losses

There is no accurate way to convert wheel power to flywheel power but that does not stop most people from coming up with ridiculous claims about 20% or 15hp or anything else they can grab out of thin air. It just can't be done. You can make a bullshit guess but that is all it is.

I have seen test sheets from a 60s F1 team that used to dyno the engines and then fit them to cars and then dyno the car. The results were all over the place. There is lots of ways that HP can go missing.

If you want flywheel HP you need to measure the HP at the flywheel, there is no other way.

Thanks Morris 1100, I was just curious if there was a "mini" rough indicator. I know that a "Porsche" has a gerneral rule of thumb with the rear engine thinghy.... Thought mini might as the engines ontop of the box.

Cheers

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1964 Grp Nb Cooper S
1976 911 3.6 Circuit Car
1969 911T Grp Sb Historic Racer
2009 LC200 V8 TDI.... 660nm..
2011 Golf VI, TSI

Blokeinamoke,

Does the colour of my flyheel effect the calculation ?

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1964 Grp Nb Cooper S
1976 911 3.6 Circuit Car
1969 911T Grp Sb Historic Racer
2009 LC200 V8 TDI.... 660nm..
2011 Golf VI, TSI

no - its the universal question to replace the impossible answer

There is no "rule of thumb" it is just guesswork. Porshe people are good at guesswork (how else can you explain the 917 hp figures?)
How do you calculate the gearbox losses? There are so many ways a gearbox can lose power. The losses are variable.

Thanks Morris 1100, Appreciate your input

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1964 Grp Nb Cooper S
1976 911 3.6 Circuit Car
1969 911T Grp Sb Historic Racer
2009 LC200 V8 TDI.... 660nm..
2011 Golf VI, TSI

There are tables for G50 boxed 911s. From recollection they are sliding scale based on "estimated" power losses variable on revs and atw number. The higher the atw number the greater the loss - but they are really rough and are guesses only.

They also available for non quad cam 356s

I have also seen them for syncro boxed six cylinder jags - however when compared to reality they were quite conservative - the losses were actually much higher.

oh yeah,,, there are drop gar losses,,, depends on how new/old/worn/SC etc

the gearbox losses,,, same deal with are they new/old/worn/ rooted/ SC etc etc etc

Then diff ratio,,, same deal with the gear wear & side thrust losses on all of those above vary soooooo much between different minis

then we have the tyres,,, are they grippy soft,,, bald hard,,, hig pressure,,, low pressure,,, what diam reflects in the torque output & fd ratio etc etc etc

& then we have the good old wheel alignment issues,,, is there play in the front end causeing toe in-out,,, where is it actually poointing exactly? straight ahead? toe in? toe out?

all those differences & more change the figure

anyone,,, & that means anyon who says they can accurately work it out is just full of sh!t

Oh!!! then how hard is it strapped down onto the rollers,,, we gained about 10hp just releasing some of the strp pressue on my Kombi

go figure what you like,,, it won`t add up unless you "Think" it does

I`ve been sprooking off about it all for years & the only one who agrees with me is me good mate,,, ol` Morris1100

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

I agree Matt, rolling road derived flywheel HP are bullsh!t HP.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.