New Dyno: Gpower SKII Supercharger

[tightie]

I had a chance to head over to Gintanti today and had my car dynoed.

We did three pulls but keep in mind that it was 106º today in the valley.

These runs were done in 98ºF.

Best run:
471 HP
345 TQ

Dyno Dynmics

Thank Alex for staying later so we can dyno my car.

I wish it was colder so I could get higher numbers



I will try to get my hands on a scanner this week and upload the image better.

- Josh

[powertrip]

Congrats brotha, that's a fairly low reading dyno too .

[Eugene-TAIWAN]

yep , a cold weather is needed.

[mixja]

How much boost are you running?

[TheKosherStogie]

wow...that pretty damn good....especially w/ weather.. im must of missed you...i was over there at` 130pm... wish i could of watched ...also how much boost you running now?

[MrHarris]

Good numbers considering the temperature. My car feels like it lost 50hp when it's 100degrees outside like it has been.

[sales@ESSTuning]

Nice congrats

[Nate@IND]

Good power for that temp

[emesdub]

given the weather and the 'heart-break' dyno, those are some nice numbers.

[ersin]

I read everyone talking about the heat. Higher temp = lower density air => less power. However, the whole reason forced induction (back in the early days when it was invented for aircraft) was increase the air density. So the temperature for a forced induction engine (super or turbo charged) should not make much of a difference in power delivery. There is a chance of heat soak the higher the temperature, but other than that how much of a difference could 100 degree temperatures make on an SC engine?

Don't get me wrong, 470+ whp is great, I'm not trying to downplay the numbers. But I doubt it will get much better on a cold day.

Note that this argument won't apply to normally aspirated engines -- higher temperatures (and altitudes) make a significant power drop in NA engines.

[datbimmerdoe]

That's still good considering the temperature.

[m33]

Originally Posted by ersin

I read everyone talking about the heat. Higher temp = lower density air => less power. However, the whole reason forced induction (back in the early days when it was invented for aircraft) was increase the air density. So the temperature for a forced induction engine (super or turbo charged) should not make much of a difference in power delivery. There is a chance of heat soak the higher the temperature, but other than that how much of a difference could 100 degree temperatures make on an SC engine?

Don't get me wrong, 470+ whp is great, I'm not trying to downplay the numbers. But I doubt it will get much better on a cold day.

Note that this argument won't apply to normally aspirated engines -- higher temperatures (and altitudes) make a significant power drop in NA engines.

you my friend have no idea on what your talking about !!!!
turbo and supercharged cars have a major enemy and its name is HEAT !!!
if he dynoed in 55 to 65 deg he would gain an other 25 to 35 whp ...

[m33]

your guarenteed a 5% loss of power when heat soaked

[stylinexpat]

Nice numbers congrats and enjoy the beast See you still got that small dip though in the lower RPM's Doesn't look as bad the dip the older 330's had with the supercharger on them.

[KiokenM3]

nice #'s josh. how does it feel compared to your old setup?

[mixja]

Originally Posted by ersin

I read everyone talking about the heat. Higher temp = lower density air => less power. However, the whole reason forced induction (back in the early days when it was invented for aircraft) was increase the air density. So the temperature for a forced induction engine (super or turbo charged) should not make much of a difference in power delivery. There is a chance of heat soak the higher the temperature, but other than that how much of a difference could 100 degree temperatures make on an SC engine?

Don't get me wrong, 470+ whp is great, I'm not trying to downplay the numbers. But I doubt it will get much better on a cold day.

Note that this argument won't apply to normally aspirated engines -- higher temperatures (and altitudes) make a significant power drop in NA engines.

Disagree - superchargers increase air mass fed into the engine by compressing air (i.e. by increasing air pressure). When we talk 6PSI as an example, we are talking 6PSI above atmospheric pressure (i.e. a relative measure).

On a cold day, the air mass being fed at atmospheric pressure is greater than on a hot day (assuming all else is constant other than temperature). Because we have greater air mass at atmospheric pressure on the colder day, adding a supercharger running at 6PSI will result in greater output air mass than the same example on a hot day.

In other words, you'd need to run your supercharger at higher boost on a hot day to get the same amount of air mass (power) produced at a lower boost pressure on a cold day. Of course you've never actually do this because higher boost pressure will only cause higher intake temperatures already exacerbated by the higher air temperatures, causing a reduction in timing (and resulting loss in power) or detonation if timing is static.

[Jonmartin]

[onefastdoc]

That's a great result. I'd love to get one of those. Still, it's hard to believe how much it costs to squeeze more hp out of our M3's. My old 335i made more torque than this G power blown M3 with only $600 in mods (a tune, intake, and race gas). The G power kit must be, what, $15K? This is probably the only thing that I don't like about in my M3, the ridiculous cost to obtain incremental gains in power. I guess I'll just have to get an old 2JZGTE Supra to satisfy my hp junkie needs.

[xquizit]

Originally Posted by mixja

Disagree - superchargers increase air mass fed into the engine by compressing air (i.e. by increasing air pressure). When we talk 6PSI as an example, we are talking 6PSI above atmospheric pressure (i.e. a relative measure).

On a cold day, the air mass being fed at atmospheric pressure is greater than on a hot day (assuming all else is constant other than temperature). Because we have greater air mass at atmospheric pressure on the colder day, adding a supercharger running at 6PSI will result in greater output air mass than the same example on a hot day.

In other words, you'd need to run your supercharger at higher boost on a hot day to get the same amount of air mass (power) produced at a lower boost pressure on a cold day. Of course you've never actually do this because higher boost pressure will only cause higher intake temperatures already exacerbated by the higher air temperatures, causing a reduction in timing (and resulting loss in power) or detonation if timing is static.

kidding, i get it ;]

[Lemans_Blue_M]

Originally Posted by mixja

Disagree - superchargers increase air mass fed into the engine by compressing air (i.e. by increasing air pressure). When we talk 6PSI as an example, we are talking 6PSI above atmospheric pressure (i.e. a relative measure).

On a cold day, the air mass being fed at atmospheric pressure is greater than on a hot day (assuming all else is constant other than temperature). Because we have greater air mass at atmospheric pressure on the colder day, adding a supercharger running at 6PSI will result in greater output air mass than the same example on a hot day.

In other words, you'd need to run your supercharger at higher boost on a hot day to get the same amount of air mass (power) produced at a lower boost pressure on a cold day. Of course you've never actually do this because higher boost pressure will only cause higher intake temperatures already exacerbated by the higher air temperatures, causing a reduction in timing (and resulting loss in power) or detonation if timing is static.

+1

Mixja is correct. A forced induction engine simply feeds the engine with air(positive pressure through a mechanical blower) instead of a vacuum approach used in a naturally aspirated engine.

The increased air mass produced by the supercharger produces will increase the HP & TRQ. This has nothing to do with air density.

The density of the air is dependent on three primary factors. (temperature, moisture (% humidity), and elevation) That is what determines how dense the air will be.

Forcing compressed air into the intake manifold (via centrifugal belt-driven blower), will by it's very nature create more heat. Hot air is naturally less dense, and it contains less oxygen than a cooler denser air. (assuming the same elevation and relative humidity)

Less % oxygen to burn = less power & torque. (for the same MASS air entering the engine)

There is no way around this basic truth. In fact, the more boost (MASS AIR) you attempt to run, the faster you will descend into heat soak. The larger mass of hot air will only create more heat in the combustion chamber as a by-product. The engine oil and water temperatures will become dangerously high, and the engine will shutdown to prevent catastrophic failure in extreme conditions. (via ECU programming) The heat that is being generated by compressing the air through mechanical means, must be shed prior to entering the intake manifold. (or there is going to be a problem)

Whether you use a FMIC (front mounted intercooler) or some type of Water-to-Air charge cooling system, that heat has to be neutralized or dissipated for the engine to make good consistent power. If not, the performance will continue to suffer. The engine will never perform up to it's full potential under those conditions, so simply increasing the boost would be counter-productive. The ECU will pull timing anyway, (once the combustion chamber temps get to high) so it's pointless to use this to compensate. There is no free lunch here.

When the outside air temperature (before entering the blower) is already extremely high, the prospects for making max power is not very realistic. The blower will only make things worse as it compresses the intake charge to create boost. (resulting in even more heat) The ECU will pull ignition timing to prevent detonation (knock), and you are going to lose 15-20% off your PEAK hp and trq numbers. (compared to the ideal air temperature dyno numbers) The difference is pretty dramatic on a forced induction car.

The blower is constantly generating heat, and if the environmental conditions are extreme enough (which appears to be the case in Jon Martin's dyno run) then the performance of the car will reflect that...

The air temperature in his dyno run was already pushing 100 degrees Fahrenheit...before he even started the car. That's a huge impediment to his performance right off the bat. That's also 30+ degrees higher than the ideal air temperature for making max power & trq. (~65 degrees Fahrenheit)

[TOOMANYCARS]

Very impressive numbers, on a Dynojet, you would be over 500whp, congrats!

[J08M3]

Originally Posted by ersin

I read everyone talking about the heat. Higher temp = lower density air => less power. However, the whole reason forced induction (back in the early days when it was invented for aircraft) was increase the air density. So the temperature for a forced induction engine (super or turbo charged) should not make much of a difference in power delivery. There is a chance of heat soak the higher the temperature, but other than that how much of a difference could 100 degree temperatures make on an SC engine?

Don't get me wrong, 470+ whp is great, I'm not trying to downplay the numbers. But I doubt it will get much better on a cold day.

Note that this argument won't apply to normally aspirated engines -- higher temperatures (and altitudes) make a significant power drop in NA engines.

think intercoolers