what sort of 1.4 mile times is everyone running?

[Adrian_Visser]

whats that in BHP? everyone over here uses figures at the fly instead of at the wheels. stupid imo but what can u do.

Bhp (brake horsepower) IS flywheel horsepower and is purely estimated if the engine is tested on a wheel dyno. Whp (wheel horsepower) is what is measured at the wheels and let's be honest it isn't even all that accurate considering the variances between different dynos and atmospheric conditions.

[DmcL]

i know but for some stupid reason all u ever hear people talking about here is BHP.. i know its a crock of shit and doesnt really tell anything but im wondering that that high 155whp would be roughly in BHP to give me an idea of where i should be compared to that.

any more RR runs i do ill be requesting graphs/readings on WHP not calculated HP at the fly bullshit..

[DmcL]

i know but for some stupid reason all u ever hear people talking about here is BHP.. i know its a crock of shit and doesnt really tell anything but im wondering that that high 155whp would be roughly in BHP to give me an idea of where i should be compared to that.

any more RR runs i do ill be requesting graphs/readings on WHP not calculated HP at the fly bullshit..

[nando]

well figure the average M20B25 dynos between 130-145whp (just from what I've seen). Take the highest # to be conservative (because we want the lowest correction factor), and assume it's making the factory 168bhp. 145/168 = 14% loss. 155whp*1.14 = 177bhp. even 20% would be optimistic.

No idea how you get a 28% drivetrain loss (discussion from another thread). that would mean out of the factory the 325i made 120whp. So either BMW *really* under-rated the M20, or those UK blokes are on crack..

[UDelaware30]

i ran a 15.05 with an m20 and 4.10's
That was before the war chip and maf conversion. Would have loved to go back and run some 14's but pulled the motor for an m52 before i had a chance

[brody]

well figure the average M20B25 dynos between 130-145whp (just from what I've seen). Take the highest # to be conservative (because we want the lowest correction factor), and assume it's making the factory 168bhp. 145/168 = 14% loss. 155whp*1.14 = 177bhp. even 20% would be optimistic.

No idea how you get a 28% drivetrain loss (discussion from another thread). that would mean out of the factory the 325i made 120whp. So either BMW *really* under-rated the M20, or those UK blokes are on crack..

Don't use a percentage PERIOD. Use a fixed HP number. We usually see between 30 and 40 HP lost through the drivetrain on ALL BMW's Brand new to Old balls e30's.

If you loose 40 HP through the drivetrain, and you DON'T change the drivetrain or testing conditions (RPM) you should still have that same XX HP loss.

If all you are doing is getting the engine to produce more power without changing gearing or driveline components, how can that same equipment loose more power?

For example, people who say 17 - 20%, we will use 20% for this example. Lets say they are making 500 WHP, they figured from before that XXXWHP/XXXBHP was 20%. They then apply that 20% to the 500 WHP to get 600 BHP. Now ask yourself, "What is a byproduct of HP? " Heat. So you go from loosing say 40 HP worth of heat through your drivetrain to loosing 100+ HP of heat. Not happening. Where is the sun under your car?! How are you now dealing with this added heat?! Your not because it isn't there.

If you are not magically housing the sun under your car, your not loosing any more HP. We have a transmission engineering company that designs transmission for military vehicles tanks etc that uses our dyno all the time and I am pretty much repeating how they explained it to me. The only way your actual loss changes is when you change the testing RPMS, or actual gearing components.

But after all, unless you are measuring AT THE CRANK, don't quote your "new" BHP use your WHP only.

[nando]

Don't use a percentage PERIOD. Use a fixed HP number. We usually see between 30 and 40 HP lost through the drivetrain on ALL BMW's Brand new to Old balls e30's.

If you loose 40 HP through the drivetrain, and you DON'T change the drivetrain or testing conditions (RPM) you should still have that same XX HP loss.

If all you are doing is getting the engine to produce more power without changing gearing or driveline components, how can that same equipment loose more power?

For example, people who say 17 - 20%, we will use 20% for this example. Lets say they are making 500 WHP, they figured from before that XXXWHP/XXXBHP was 20%. They then apply that 20% to the 500 WHP to get 600 BHP. Now ask yourself, "What is a byproduct of HP? " Heat. So you go from loosing say 40 HP worth of heat through your drivetrain to loosing 100+ HP of heat. Not happening. Where is the sun under your car?! How are you now dealing with this added heat?! Your not because it isn't there.

If you are not magically housing the sun under your car, your not loosing any more HP. We have a transmission engineering company that designs transmission for military vehicles tanks etc that uses our dyno all the time and I am pretty much repeating how they explained it to me. The only way your actual loss changes is when you change the testing RPMS, or actual gearing components.

But after all, unless you are measuring AT THE CRANK, don't quote your "new" BHP use your WHP only.

That was my argument in the other thread.

[Dark Helmet]

thanks guys... I know what it did on that dyno, and don't really care what the "conversion" should be. I'm hoping to get it to 170hp before next spring... hopefully get a first pull here in the next week or so...

[digger]

Don't use a percentage PERIOD. Use a fixed HP number. We usually see between 30 and 40 HP lost through the drivetrain on ALL BMW's Brand new to Old balls e30's.

If you loose 40 HP through the drivetrain, and you DON'T change the drivetrain or testing conditions (RPM) you should still have that same XX HP loss.

If all you are doing is getting the engine to produce more power without changing gearing or driveline components, how can that same equipment loose more power?

For example, people who say 17 - 20%, we will use 20% for this example. Lets say they are making 500 WHP, they figured from before that XXXWHP/XXXBHP was 20%. They then apply that 20% to the 500 WHP to get 600 BHP. Now ask yourself, "What is a byproduct of HP? " Heat. So you go from loosing say 40 HP worth of heat through your drivetrain to loosing 100+ HP of heat. Not happening. Where is the sun under your car?! How are you now dealing with this added heat?! Your not because it isn't there.

If you are not magically housing the sun under your car, your not loosing any more HP. We have a transmission engineering company that designs transmission for military vehicles tanks etc that uses our dyno all the time and I am pretty much repeating how they explained it to me. The only way your actual loss changes is when you change the testing RPMS, or actual gearing components.

But after all, unless you are measuring AT THE CRANK, don't quote your "new" BHP use your WHP only.

There are some losses that are fixed hp amounts but there are others which are a % loss so neither using a straight % or constant loss will never be correct.

The reason for % losses is that the more torque/power you produce the higher proportionally the friction forces that are developed (coulomb friction). So the more power you put through a transmission system the more power is lost but not a fixed percentage because there are many different modes through which losses arise

The % losses are not the only losses so a 1000hp car won’t lose the same % as a 100hp car.

A lot of hp is consumed in the tyres on a dyno and you aren’t running continuously for a long period of time at max power so while there is a lot of power lost as heat things don’t start melting. The heat is taken away through radiation, natural and forced convection etc etc.

[LowR3V'in]

What? Who the fuck is using flywheel hp? That's like measuring your dick from behind your balls.

Yeah that is a perfect way to look at it.

usually there is 2-4'' of dick behind the balls so that converts my 1'' dick to
about 5'' "behind the balls long".

Converting to bhp is bullshit and meant to make people people feel better
about their numbers.

[digger]

What? Who the fuck is using flywheel hp? That's like measuring your dick from behind your balls.

The manufacturers are, hence why europeans like to "try" and come up with something that resembles/can be compared to that.

[DmcL]

so europeans have tiny dicks then?

glad im not a native lol