# 180HP good or ok ?



## 328individual (Nov 18, 2003)

Just had my 328i dyno'd and i am putting out 180 hp on the wheels.Is that good or ok ?


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## Fast Bob (Jun 4, 2004)

This equates to about 215-220 HP @ the crank....pretty respectable for any 2.8.....my previous car (`99 528i SP) was rated at "only" 193 HP, but on the road, it *smoked* many cars with a substantially higher HP rating. 

Regards,
Bob


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## Kaz (Dec 21, 2001)

That's pretty good. Assuming this is a Dynojet, 180 would be about 205-210 at the crank with a manual. So it's pulling just over 10hp more than it's rated for.


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## SergioK (Aug 14, 2002)

According to Dinan I have 183 at the crank....  

180hp at the wheels would be fun! :thumbup:


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## HW (Dec 24, 2001)

well within the -1%/+10% output range. (191HP to 212HP)


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## RKT BMR (Sep 7, 2002)

joema pointed me to this paper by Steve Dinan on the complexities and pitfalls of accurately measuring power on a dyno. It is a great read, and would recommend everyone here go through it.

It has resulted in two decisions on my part:

I'm not going to waste my money on a dyno run unless the facility is in the ballpark of offering meaningful airflow/cooling requirements outlined by Dinan, and other important factors he describes and explains in Detail. This probably means that if and when I dyno my supercharged beast, it will be at Dinan for quite a bit of bank.

I am going to experiment with moving my IAT sensor directly into the intake path, probably right before the MAF. I can do this by inserting a short piece of rubber tubing with some hose clamps, drill a hole in it of the right size, fix and seal the sensor in place with some silicone rubber adhesive. Right now it's located in the interior air filter housing, and consistent reads 10-20 degrees hotter than the actual ambient air temperature.
Anyway, read Dinan's paper, gang. You'll love it.


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## The Roadstergal (Sep 7, 2002)

I dunno, is it good for you?

A friend of mine has 180hp. In his motorcycle. :eeps:


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## RKT BMR (Sep 7, 2002)

The Roadstergal said:


> I dunno, is it good for you?
> 
> A friend of mine has 180hp. In his motorcycle. :eeps:


Ive got 180HP between my legs too.


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## Fast Bob (Jun 4, 2004)

The Roadstergal said:


> I dunno, is it good for you?
> 
> A friend of mine has 180hp. In his motorcycle. :eeps:


In the world of Power-To-Weight ratio, crotch-rockets rule.....

Regards,
Bob


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## HW (Dec 24, 2001)

The Roadstergal said:


> I dunno, is it good for you?
> 
> A friend of mine has 180hp. In his motorcycle. :eeps:


what's the engine preference? big bore or long strokes? :eeps:


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## The Roadstergal (Sep 7, 2002)

HW said:


> what's the engine preference? big bore or long strokes? :eeps:


It's a four-banger, I hear.


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## Kaz (Dec 21, 2001)

RKT BMR said:


> joema pointed me to this paper by Steve Dinan on the complexities and pitfalls of accurately measuring power on a dyno. It is a great read, and would recommend everyone here go through it.


I'll try and read this later, but the first thought that popped into my head was that Dinan doesn't want to be pwn3d by people who dyno their Dinan cars and find ZERO gains. :rofl:


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## Fast Bob (Jun 4, 2004)

Kaz said:


> I'll try and read this later, but the first thought that popped into my head was that Dinan doesn't want to be pwn3d by people who dyno their Dinan cars and find ZERO gains. :rofl:


This is a valid point....any dyno test should`nt be considered as the "last word", more an indicator of whether you`re headed in the right direction with your modifications.

Regards,
Bob


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## docrobot (Jun 23, 2004)

It looks like you have about 211 BHp at the crank if you use the often quoted 15% loss to the manual drivetrain. 

Your 180 BHp at the wheels divided by 0.85 makes 211 BHp and change...

So, is your 2.8L stock, or not?


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## RKT BMR (Sep 7, 2002)

Kaz said:


> I'll try and read this later, but the first thought that popped into my head was that Dinan doesn't want to be pwn3d by people who dyno their Dinan cars and find ZERO gains. :rofl:


I hear ya. I was a bit skeptical before I read the paper myself.

However, you can't argue with data and empirical procedure. You've got to read the paper to understand what I'm talking about.

Still, as a service to the lazy out there, the paper can be summed up this way: The dyno shop better have a really, really, REALLY big cooling fan for airflow.


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## HW (Dec 24, 2001)

docrobot said:


> It looks like you have about 211 BHp at the crank if you use the often quoted 15% loss to the manual drivetrain.
> 
> Your 180 BHp at the wheels divided by 0.85 makes 211 BHp and change...
> 
> So, is your 2.8L stock, or not?


http://www.bimmerfest.com/forums/showpost.php?p=805803&postcount=10


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## 328individual (Nov 18, 2003)

Thanks for the replies guys.

My car is not standard,have had a cutom made exhaust put on,removed the cats and put in a performance filter into the existing airbox.I am going to unichip it next which should give me 10 - 15 % power increase.

What is the standard HP on the crank for these cars.


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## docrobot (Jun 23, 2004)

Opinions vary, but expect to lose between 20% and 25% power to drivetrain loses on Automatics, even those from Bavaria.

A *20% loss* would give you *225 BHp* at the crank.

A *25% loss* would give you *240 BHp* at the crank.

That Dinan article is an eyeopener, a similar article was printed recently in one of the US Car Mags.

Another recent Dyno article of interest is the one that starts on Page 197 of the August 2004 issue of Sports Compact Car Mag. Called *"What's Wrong With Your Dyno"*, it compares 7 different makes and models of dynos in 2WD and 4WD comparisons. As a bonus, it describes how each of the different dyno models work to calculate front and rear wheel torque and thus, Bhp.

In 2wd mode, peak corrected horsepower varied from* 174 BHp down to 132 BHp!* Torque varied from *205 to 169!* On 3 of the similar (thought to be repeatable and comparable) DynoJet Dynos, *the corrected numbers varied 9 BHP* from 165 to 174.

Those of you who put down power to the ground with all four wheels will be even more shocked to see the 4WD Dyno tests of the same vehicle! When tested on 6 of the same 7 dynos that could test 4WD, the Dynos showed a range of *157 Bhp down to 102 BHp*!!! (A 10 - 23% difference!)

In the conclusions section of the article, they state that the power curves as well as the peak numbers varied between the dynos.



> "_Even if there is better consistency, the question of sweep time, fan setup, roller weight, and correction factors makes comparing different results from different dynos from different operators a sketchy proposition at best._"


In closing they suggest for best results to stick to one Dyno so you get consistent and comparable runs.

Although Sport Compact Car Mag has the hots for Japanese Cars; especially when they are modded with tens of thousands of dollars of JDM parts, they do their best to make sense of things automotive.


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