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For those who have done all of the intake & exhaust mods (and did not update their ECU to compensate in anyway) do you have any pre & post Dyno results?

Reason for the question... another autoX and bracket racer that I compete with brought up a good point about our cars:
He contends "our cars monitor and adjust the air/fuel ratio ... no matter what intake mods you have, you won't change the power of the engine because the engine only allows a certain amount of air through"
furthermore, "the CAI may change the tone of your exhaust, but the power gains will be nearly imperceptible"

As far as exhaust, headers & full systems can reduce both weight and resistance... but I am curious how that affects the HP and Torque curves. In many turbo cars, reducing the back-pressure bleeds low end torque in trade for high RPM HP.

I am highly interested to see the impact the exhaust and or intake changes without updating the software to compensate.



Thank you in advance for any and all input to the discussion!
 

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Low end torque? What's that? I don't recall having any to lose. hiha

Ask RPi (Race Precision), a sponsor and widely regarded as straight shooters, for dyno charts of their intake mods (scoops, block off plates and BMC filters) and exhaust system if you think there are no breathing improvements possible for an M6.

I'm not saying you should only consider RPi for mods, but I think you can trust their posted dyno charts to prove the point to your buddy.

And the RPi intake kit is reasonably priced and widely used by members here (including me) and I can't recall anyone regretting their purchase. But there are other intake systems out there too. But get some feedback or do some searching as some kits can actually reduce power (especially when the engine heats up).

There are lots of exhaust systems. Modest HP gains - most members get them for their sound (which varies by mfgr).

Good luck
 

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What your friend said makes sense.

I have the RPI scoops / cold air intake and block off plates.
I also have the BMC filters, and Tubi Rumore exhaust.
The difference in performance after the above mods was negligible.

I recently had my ECU software upgraded by Active Autowerke and I asked them to tune the software per my mods above.

The difference post ECU software tune is amazing. I can feel the difference big time in horsepower and torque increase.

Regarding dyno - I gave up on that.
When I had my M5, I dynoed my M5 six times, all with different inconsistent results.
Too many variables and different dyno makers produces different results.

Dyno Jet and Mustang Dyno produced different results.
Temperature and barometric pressure makes a difference.
Engine temp and fan blower used also makes a difference.
Outside temperature makes a difference.
Like I said, too many variables.

For the fun of it - I dynoed my M6 4 months ago using a dynojet.
Dyno results were not even close to BMW spec.

I now trust my butt-o-meter better than dyno machines.
 

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We did a pre and post dyno of the BMW M5 Touring (V10) while measuring air / fule ration at Supersprint in Italy. Gain was 40 HP without ECU changes I beleive I recall.

See the writeup here:

http://www.m5board.com/vbulletin/e6...d-gain-40-hp-full-system-40-min-hd-video.html





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For those who have done all of the intake & exhaust mods (and did not update their ECU to compensate in anyway) do you have any pre & post Dyno results?

Reason for the question... another autoX and bracket racer that I compete with brought up a good point about our cars:
He contends "our cars monitor and adjust the air/fuel ratio ... no matter what intake mods you have, you won't change the power of the engine because the engine only allows a certain amount of air through"
furthermore, "the CAI may change the tone of your exhaust, but the power gains will be nearly imperceptible"

As far as exhaust, headers & full systems can reduce both weight and resistance... but I am curious how that affects the HP and Torque curves. In many turbo cars, reducing the back-pressure bleeds low end torque in trade for high RPM HP.

I am highly interested to see the impact the exhaust and or intake changes without updating the software to compensate.



Thank you in advance for any and all input to the discussion!
 

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For those who have done all of the intake & exhaust mods (and did not update their ECU to compensate in anyway) do you have any pre & post Dyno results?

Reason for the question... another autoX and bracket racer that I compete with brought up a good point about our cars:
He contends "our cars monitor and adjust the air/fuel ratio ... no matter what intake mods you have, you won't change the power of the engine because the engine only allows a certain amount of air through"
furthermore, "the CAI may change the tone of your exhaust, but the power gains will be nearly imperceptible"
He's wrong on engines limiting air that comes through, but right on engine gains which are minimal, with or without a tune. Intake mods just don't do a ton on our cars. When you make 500hp already, it takes a lot of power to notice a difference. Intake mods don't add that much in horsepower.


As far as exhaust, headers & full systems can reduce both weight and resistance... but I am curious how that affects the HP and Torque curves. In many turbo cars, reducing the back-pressure bleeds low end torque in trade for high RPM HP.

I am highly interested to see the impact the exhaust and or intake changes without updating the software to compensate.



Thank you in advance for any and all input to the discussion!
Cat back exhausts won't do much, but headers and removing cats should help decently
 

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My base dyno mods included: Dinan Stage 1 and Stage 3 tune, Dinan highflow air intake, Dinan 3.91 rear differential, RPI underpulley, and RPI scoops. The after was with RPI GT headers, which basically remove the primary cats, and a custom tune. Unfortunately it doesn't look like the base include the AFR as it reads a constant 10. I was very happy with the gains especially the low and mid torque.
 

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I will summarize for you what I have learned after owning an M5 and now an M6.

BMW has done a great job getting every ounce of power available on their M motors that any mods you do to the engine other than forced air induction or stroker engine - improvement will be minimal and not even worth it in my opinion not unless you are like the rest of us that just enjoys tinkering with our cars.

But as far as bang for the buck:

Here are examples:

Cold Air Intake: ~ + 3hp
Better intake filters: ~ + 1 hp.
High performance exhaust: ~ + 6hp
Pulley: ~ + 3 hp
Headers: ~ + 30 hp.
Software tune: ~ + 15hp.
Etc.

The above costs an average of around $12K for a mere 60 additional horses : (

The most power gain are from having a stroker motor or supercharger or turbo charger kit installed.
But nothing is cheap. Dinan, G Power, ESS, etc out there are in the mid double figures.
 

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I will summarize for you what I have learned after owning an M5 and now an M6.

BMW has done a great job getting every ounce of power available on their M motors that any mods you do to the engine other than forced air induction or stroker engine - improvement will be minimal and not even worth it in my opinion not unless you are like the rest of us that just enjoys tinkering with our cars.

But as far as bang for the buck:

Here are examples:

Cold Air Intake: ~ + 3hp
Better intake filters: ~ + 1 hp.
High performance exhaust: ~ + 6hp
Pulley: ~ + 3 hp
Headers: ~ + 30 hp.
Software tune: ~ + 15hp.
Etc.

The above costs an average of around $12K for a mere 60 additional horses : (

The most power gain are from having a stroker motor or supercharger or turbo charger kit installed.
But nothing is cheap. Dinan, G Power, ESS, etc out there are in the mid double figures.


wow Dan congrats for your AA ecu tuning , how is it ??
 

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My base dyno mods included: Dinan Stage 1 and Stage 3 tune, Dinan highflow air intake, Dinan 3.91 rear differential, RPI underpulley, and RPI scoops. The after was with RPI GT headers, which basically remove the primary cats, and a custom tune. Unfortunately it doesn't look like the base include the AFR as it reads a constant 10. I was very happy with the gains especially the low and mid torque.
I'm not sure I completely understand...

Are you saying that your Dinan Stage 1 & Stage 3 ECU tune did NOT remap your air & fuel? That's directly contradicting to their product description:


Dinan D900-51M Product Description said:
Product Description

Dinan Engine Software raises the factory rev-limiter by 150 rpm (8400 rpm maximum), endowing the V-10 with a broader power band and greater road speed potential in each gear. The software also removes the top speed governor, enabling the cars to attain their ''natural'' top speed; and the V-10s WILL pull right to red-line in top gear! The software also speeds up throttle response, providing a sportier feel and improved modulation capabilities.

The combination of Dinan's re-calibration of ignition timing and air/fuel ratios, along with a simple modification to the stock air filter elements, produces a maximum gain of 5 hp @ 8100 rpm and 5 lb-ft torque @ just 3000 rpm. Dinan's software also provides re-calibration of the factory ''torque limiting'' programming, ensuring that maximum power is available under varying driving conditions.

Please clarify if I'm understanding you correctly...

-b.
 

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I will summarize for you what I have learned after owning an M5 and now an M6.

BMW has done a great job getting every ounce of power available on their M motors that any mods you do to the engine other than forced air induction or stroker engine - improvement will be minimal and not even worth it in my opinion not unless you are like the rest of us that just enjoys tinkering with our cars.

But as far as bang for the buck:

Here are examples:

Cold Air Intake: ~ + 3hp
Better intake filters: ~ + 1 hp.
High performance exhaust: ~ + 6hp
Pulley: ~ + 3 hp
Headers: ~ + 30 hp.
Software tune: ~ + 15hp.
Etc.

The above costs an average of around $12K for a mere 60 additional horses : (

The most power gain are from having a stroker motor or supercharger or turbo charger kit installed.
But nothing is cheap. Dinan, G Power, ESS, etc out there are in the mid double figures.
Dan my friend,

We will open a HUGE discussion here. I think you have a very pessimistic view of potential gains using bolt on parts.

Let me explain myself.

I asked directly and blantly ( and I insisted ), Gabriel from RPI what is the expected whp gain using the following parts :

1) RPI ram air induction ( full set )
2) RPI underdrive pulley
3) RPI gt exhaust.
4) Ess software upgrade.

The answer was very specific and with no doubts. " Based on many-many dynos on their own dynometer the expected whp gain
-as seen in many clients cars- is 45-50 hp using 93 octane fuel or 98 for Europe.Adding their headers should produce another 20-25
whp gain using Ess software stage 2."

Let us take the conservative side. 45+20= 65 whp. Or almost 80 hp at the crank. These numbers are also stated in the Evosport
sight as well. Also another company I respect - Evolve - suggests the same figures.

Now to the hard facts. I have installed on my car, software, RPI ram air ( full set ) and underdrive pulley.

Pre and post dynos showed a constant ~33-35 whp gains using 100 octane gas. The dynometer was a Maha dynometer, one of the most

accurate and expensive dynometers in the world ( a very conservative one also ) that has the ability to measure any underdrive pulley

gains.( Not all can ).

This is ~ 40 crank hp gain WITHOUT exhaust and headers. My understanding is that installing a decent set of headers and exhaust and

upgrading the software to stage 2, should produce at least 25 whp more.

I think that extracting almost 70+ crank horsies from an already highly tuned engine, with a ~12.000 $ budget is not so bad.

570-580 crank horses is a very respectable figure for a normally aspirated engine of 5 litres.

Regards,

George:byebye:
 

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Hi George.

I understand what you are saying.

All I am saying is - for an average guy like me (not rich by any means) an additional 70 horses for $12,000.00 is a lot of money to spend on mods and I dont plan on going that route.

Simple bolt on inexpensive mods no problem,but $12K for 70 horses is out of the question as my pocket is not very deep.

But if money is no object for some folks here - heck go for it! Like you said - its only money. But I cant spend it if I dont have it.

And before I spend $12,000.00 to get 70hp - I would rather give that money to my niece to help pay for her college.

I love my beast but I love my niece more.
 

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Dan my friend,

I think you misunderstood my intention.

First of all I NEVER said it is only money. Please read my post carefuly.

My intention was simply to point out that from the "bang for the buck" point of view, the gains of ~70 horsies against the cost of

approximately 12k, is reasonable, given that we are talking about an already stretched motor.

Purely technically speaking I doubt that your pessimistic bat-o-meter measurements are accurate ( haha ) ,because if they are then

some very respected companies out there are lying.

It took Lamborghini 7 years to take Gallardo from 500 hp to 570.

All in all considered getting some reliable 570 horsies from a 100.000 dollars vehicle, sounds good to me.

Put some decent wheels, suspension, brakes and some cosmetic changes and you have the BEST GT car in the world with 570-580

hp. Total cost ??? 100.000 + ~20.000 for mods.

Now please tell me what other true beast gt car you can buy new, with such potential for that money ???

That was what I was trying to point out.

Now if it is rational to spend that money ? There can't be an answer here. Every person knows his own pocket and his own priorities.

Considering the fact that this discussion is among mature grown up men, then every angle of life MUST BE strongly examined before

spending this kind of money on cars. I totally agree that family priorities are above everything.

Sincerely yours,

George
 

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I understand your point better now George. Thanks for explaining.

We are all good my friend! Point well taken, all is understood, we are all good!

I still trust my butt-o-meter compared to all the different Dyno's out there though.

My butt gets massaged by my girlfriend on a regular basis. I dont think any Dyno maker out there can top that :biggrin:
 

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Hi George.

I understand what you are saying.

All I am saying is - for an average guy like me (not rich by any means) an additional 70 horses for $12,000.00 is a lot of money to spend on mods and I dont plan on going that route.

Simple bolt on inexpensive mods no problem,but $12K for 70 horses is out of the question as my pocket is not very deep.

But if money is no object for some folks here - heck go for it! Like you said - its only money. But I cant spend it if I dont have it.

And before I spend $12,000.00 to get 70hp - I would rather give that money to my niece to help pay for her college.

I love my beast but I love my niece more.
+1

Totoo! Pakikisama, pakikiramdam at bayanihan. :byebye:

Now I feel guilty for what I've already spent on the beast in just 3 months.. :dunno:

I guess it's always important to keep a good perspective and reflect on your priorities often...

-b.
 

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Dan my friend,

I think you misunderstood my intention.

First of all I NEVER said it is only money. Please read my post carefuly.

My intention was simply to point out that from the "bang for the buck" point of view, the gains of ~70 horsies against the cost of

approximately 12k, is reasonable, given that we are talking about an already stretched motor.

Purely technically speaking I doubt that your pessimistic bat-o-meter measurements are accurate ( haha ) ,because if they are then

some very respected companies out there are lying.

It took Lamborghini 7 years to take Gallardo from 500 hp to 570.

All in all considered getting some reliable 570 horsies from a 100.000 dollars vehicle, sounds good to me.

Put some decent wheels, suspension, brakes and some cosmetic changes and you have the BEST GT car in the world with 570-580

hp. Total cost ??? 100.000 + ~20.000 for mods.

Now please tell me what other true beast gt car you can buy new, with such potential for that money ???

That was what I was trying to point out.

Now if it is rational to spend that money ? There can't be an answer here. Every person knows his own pocket and his own priorities.

Considering the fact that this discussion is among mature grown up men, then every angle of life MUST BE strongly examined before

spending this kind of money on cars. I totally agree that family priorities are above everything.

Sincerely yours,

George
It took lambo 7 years to bump the car to that kind of horsepower because it couldn't encroach on the Murcielago's power numbers, and, because it has to be 70 RELIABLE horsepower that they don't have to worry about hindering durability. It's a lot easier and cheaper as a consumer to slap on 70hp onto an M6. Lambo will likely take that extra step to ensure the drivetrain, cooling, brakes and suspension are beefed up to compensate, perform rigorous tests, etc.

Doing $12k in mods (before taxes and install) listed above and then adding wheels/tires, suspension, brakes, cosmetic changes etc is going to bring your total WITH installation to more than $20k over sticker price. You're probably going to be looking at closer to $130,000 total.

For that kind of money, you could consider a 4.2L Audi R8 with an MTM supercharger package which yields 560hp. Maybe a 911 turbo suits your fancy for about $135k.
 

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Hey bud,

Your Filipino language vocabulary continues to amaze me!
Are you sure you dont have Filipino blood in you? : )
You may be my long lost cousin or something......

Yes, we need to take care of ourselves and our family too, and need to share our blessings a little bit as others are not as fortunate.

But never feel guilty.
You earned it, you deserve it and you can spend it anyway you want.
And I have always felt that way.

Its just once in a while - I think we all need to look at the bigger picture.

Take care bud.

+1

Totoo! Pakikisama, pakikiramdam at bayanihan. :byebye:

Now I feel guilty for what I've already spent on the beast in just 3 months.. :dunno:

I guess it's always important to keep a good perspective and reflect on your priorities often...

-b.
 

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It took lambo 7 years to bump the car to that kind of horsepower because it couldn't encroach on the Murcielago's power numbers, and, because it has to be 70 RELIABLE horsepower that they don't have to worry about hindering durability. It's a lot easier and cheaper as a consumer to slap on 70hp onto an M6. Lambo will likely take that extra step to ensure the drivetrain, cooling, brakes and suspension are beefed up to compensate, perform rigorous tests, etc.

Doing $12k in mods (before taxes and install) listed above and then adding wheels/tires, suspension, brakes, cosmetic changes etc is going to bring your total WITH installation to more than $20k over sticker price. You're probably going to be looking at closer to $130,000 total.

For that kind of money, you could consider a 4.2L Audi R8 with an MTM supercharger package which yields 560hp. Maybe a 911 turbo suits your fancy for about $135k.
I have already paid more than 130.000 $ for my M6 and I do not regret it one moment.

We are talking gt cars. Neither R8 nor 911 turbo are gt cars.

I can't imagine that a ram-air, a pulley, an exhaust and an upgraded Ecu are not reliable or they stress other parts of the car.

As for the rigorous tests of Lamborgini I have some slight doubts. I have seen in YouTube multiple Lambos and Ferraris catch fire

while sitting at a trafic light. I have not seen ONE Bmw have such bad luck ( ???? ). So much for rigorous tests and durability.

I am afraid sir that, with all due respect, you missed the point of my discussion with Dan ( Whatheheck ).
 
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