Lost 20 BHP on a low mileage engine

[R60BBA]

Today I decided to pluck some courage and put my 10 year old E86 on the dyno @ Evolve Automotive.

However I was quite disappointed when the computer displayed a reading of 246.8HP after 3 runs.

The car has only done 33,000 miles and I left scratching my head in wonder of where my 20 horses have disappeared to. Perhaps Ascot? Or maybe Epsom...

The technician asked whether I had the plugs and filter done, to which I confirmed as the car had an Inspection II in September 2017.

The technician advised that I could gain 10/12HP with an Evolve map, but at a cost of £600.

He also suggested that I get a carbon clean and/or a terraclean to get rid of the carbon deposits in the valves/injectors and also the cats.

Has anyone else had these sort of results? If so what did you do?

[Ducklakeview]

TBH, a 12 bhp gain is, in my mind the very most you can get with a remap on these engines. However, I'd also be taking the figures you've ended up with cautiously anyway. At the end of the day, there are so many variables when it comes to dyno tresting, that two runs on the same car rarely give the exact same figures.

Mike

[pvr]

Not to mention that you would not know what the car produced straight out of the factory.

[rally-chris]

I'd rule out the carbon deposits theory as the N52 engine is not direct injection and that's where the carbon buildup problems occur in recent BMW engines (e.g. N53 on) - Unless you have evidence that the crank case breather has given problems in the past and lots of oil has been sucked back into the engine intake.

Chris

[srhutch]

It will be those shims you had adjusted

[TomK]

Today I decided to pluck some courage and put my 10 year old E86 on the dyno @ Evolve Automotive.

However I was quite disappointed when the computer displayed a reading of 246.8HP after 3 runs.

The car has only done 33,000 miles and I left scratching my head in wonder of where my 20 horses have disappeared to. Perhaps Ascot? Or maybe Epsom...

The technician asked whether I had the plugs and filter done, to which I confirmed as the car had an Inspection II in September 2017.

The technician advised that I could gain 10/12HP with an Evolve map, but at a cost of £600.

He also suggested that I get a carbon clean and/or a terraclean to get rid of the carbon deposits in the valves/injectors and also the cats.

Has anyone else had these sort of results? If so what did you do?

I would agree, dyno numbers need to be taken with a pinch of salt in isolation, they are only really useful for comparing modifications with a known baseline, even then there are still variables that will affect the accuracy.
Personally I'd wouldn't really trust any results from a dyno run where that place also happens to sell remaps, it's so easy for the operator to affect things apparently
Take it somewhere independent if you're really that fussed about knowing, and ideally another identical car to compare with, even then tyres can make a difference.
What is most important from a run is not the peak numbers but the shape of the curve, you want to be looking for any big peaks/troughs (which could point towards any issues), straight line's good.

[R60BBA]

Today I decided to pluck some courage and put my 10 year old E86 on the dyno @ Evolve Automotive.

However I was quite disappointed when the computer displayed a reading of 246.8HP after 3 runs.

The car has only done 33,000 miles and I left scratching my head in wonder of where my 20 horses have disappeared to. Perhaps Ascot? Or maybe Epsom...

The technician asked whether I had the plugs and filter done, to which I confirmed as the car had an Inspection II in September 2017.

The technician advised that I could gain 10/12HP with an Evolve map, but at a cost of £600.

He also suggested that I get a carbon clean and/or a terraclean to get rid of the carbon deposits in the valves/injectors and also the cats.

Has anyone else had these sort of results? If so what did you do?

I would agree, dyno numbers need to be taken with a pinch of salt in isolation, they are only really useful for comparing modifications with a known baseline, even then there are still variables that will affect the accuracy.
Personally I'd wouldn't really trust any results from a dyno run where that place also happens to sell remaps, it's so easy for the operator to affect things apparently
Take it somewhere independent if you're really that fussed about knowing, and ideally another identical car to compare with, even then tyres can make a difference.
What is most important from a run is not the peak numbers but the shape of the curve, you want to be looking for any big peaks/troughs (which could point towards any issues), straight line's good.

Meh, my fuel economy is low 20s which is why I think the figures may be near accurate? How do tyres come into the equation?

See attached a copy of the report

[TomK]

Today I decided to pluck some courage and put my 10 year old E86 on the dyno @ Evolve Automotive.

However I was quite disappointed when the computer displayed a reading of 246.8HP after 3 runs.

The car has only done 33,000 miles and I left scratching my head in wonder of where my 20 horses have disappeared to. Perhaps Ascot? Or maybe Epsom...

The technician asked whether I had the plugs and filter done, to which I confirmed as the car had an Inspection II in September 2017.

The technician advised that I could gain 10/12HP with an Evolve map, but at a cost of £600.

He also suggested that I get a carbon clean and/or a terraclean to get rid of the carbon deposits in the valves/injectors and also the cats.

Has anyone else had these sort of results? If so what did you do?

I would agree, dyno numbers need to be taken with a pinch of salt in isolation, they are only really useful for comparing modifications with a known baseline, even then there are still variables that will affect the accuracy.
Personally I'd wouldn't really trust any results from a dyno run where that place also happens to sell remaps, it's so easy for the operator to affect things apparently
Take it somewhere independent if you're really that fussed about knowing, and ideally another identical car to compare with, even then tyres can make a difference.
What is most important from a run is not the peak numbers but the shape of the curve, you want to be looking for any big peaks/troughs (which could point towards any issues), straight line's good.

Meh, my fuel economy is low 20s which is why I think the figures may be near accurate? How do tyres come into the equation?

See attached a copy of the report

I don't understand, you think your fuel economy is showing how well the engine is performing? In comparison to what figures? Someone who drives the exact same roads as you and in the exact same way? What is your definition of 'near accurate'? If that was say +/- 10% then you're within that.

For tyres, the difference in compound (slip on the rollers) , circumference (gearing) and weight (rotational inertia) can make a difference albeit small between 2 otherwise identical cars.

[TomK]

Your chart line looks pretty similar to other n52s out there, I would say your engine is just fine.

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[Smartbear]

The evolve Dyno is definitely not optimistic & tends to read low compared to others
I’ve just looked & the n52 remap is £499 on their website?

4702A335-92E6-4559-8FAD-05B1356CB809.jpeg (302.04 KiB) Viewed 956 times

Rob

[Tcochrane92]

Are you trying to compare your Dyno wheel brake horsepower with the claimed horsepower by BMW? If you are, your car is making the correct amount of power

HP and BHP are different things. HP is theoretical power produced at the output shaft of the engine. Bhp is power produced at the wheels on a Dyno (after braking forces are deducted)

Screenshot_20180202-202825.jpg (94.12 KiB) Viewed 913 times

Otherwise I must be misunderstanding your post

[Yorkie Z]

I'd start by looking down the side of the seat, I lose all kinds of stuff there. Your probably find yours horses

[original guvnor]

Company that makes a living out of remaps and mods dynos a car below factory output. Maybe I'm a cynic but turkeys don't vote for an early Christmas.

[TomK]

Otherwise I must be misunderstanding your post

I think you're mis-reading the dyno 'numbers'. Those showing are if I'm not mistaken 'corrected' engine power not wheel horsepower.
That's the thing with any wheel dyno, you can make a 'corrected' engine power number pretty much anything you like by fiddling with the drag (drivetrain loss).

[Tcochrane92]

Otherwise I must be misunderstanding your post

I think you're mis-reading the dyno 'numbers'. Those showing are if I'm not mistaken 'corrected' engine power not wheel horsepower.
That's the thing with any wheel dyno, you can make a 'corrected' engine power number pretty much anything you like by fiddling with the drag (drivetrain loss).

I've never had a Dyno run with 'corrected' numbers because you cannot accurately predict drivetrain brake losses

I'm sure in this case, only the guy who ran the Dyno will be able to tell us.

Even then, a map won't give you much power and torque gains on the N52 as they're already working at peak power and kept inline by the knock sensor (assuming it's a stock drivetrain set up)