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Racing Dynamics

The Racing Dynamics headers look pretty good. Has anyone any personal experience of these particular products. They claim 551hp with FULL headers, sport cats and silencers plus modifed ECU.
I had quite a few discussions with Mike cooper of DMS in the UK and he said that there was quite a variation on the power outputs that they had seen on the V10's. All positive and in standard form they were between 505 and 525+.
His ECU works well (BMW CAR magazine) and runs with a Gallardo on a rolling start all the way to 180mph. Claims 544hp on that particular car which they own.
 

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Wolverine said:
No way they designed those 'kinks' into the headers for airflow. It is impossible to accurately model airflow inside irregular geometries like those in the M5 headers.

The best explanation I've heard for the kinks is they are necessary to get the pipes into the catalytic converter. With aftermarket headers/converters, you don't have that restriction, and the flow can be smoothed out considerably
Ah, I hadn't considered that! (just kiddin)
 

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Vee Ten GP said:
The Racing Dynamics headers look pretty good. Has anyone any personal experience of these particular products. They claim 551hp with FULL headers, sport cats and silencers plus modifed ECU.
I had quite a few discussions with Mike cooper of DMS in the UK and he said that there was quite a variation on the power outputs that they had seen on the V10's. All positive and in standard form they were between 505 and 525+.
His ECU works well (BMW CAR magazine) and runs with a Gallardo on a rolling start all the way to 180mph. Claims 544hp on that particular car which they own.
Post some picts and data and cost. The only ones that I've seen are supersprint ($$$$).
 

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It is all related to airflow, temperature and momentum. I don't think BMW would pinch headers to make them fit more easily. Having larger diameters means airflow is slower, temperature lower, loss in torque. BMW is trying to compromise between bhp and torque. A good exhaust builder wants to give you more bhp.

Frank.
 

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I was fortunate enough to be able to dyno my C5 Z06 before and after certain mods. We ran a baseline of 351 rwhp. After a cool-down, we put on a GHL cat-back exhaust and picked up 11 rwhp. Then we put on a Haltech "sidewinder" intake and picked up another 4 rwhp. So I picked up 15 rwhp through those mods, as measured on the dyno (SAE corrected). Same day, same dyno.

I ultimately went back to the same shop and installed TPIS headers, Random Tech cats, a 160 degree t-stat, and had the computer re-programmed through what is known as "LS1-edit". Although I did not run a baseline before this last batch of work, car ultimately put down 392 rwhp (26rwhp peak improvement) with those mods on the same dyno.

Because so many C5 Z06 owners modify their cars and run baseline dynos, there was a fair amount of data to compare on the corvette boards. So people were not stuck relying on the bogus claims of the companies that made these pieces. And because there was so much data out there, it probably kept these companies more honest than they otherwise would have been.

The point here is that guys who mod their cars should really try to get proper SAE corrected before and after dyno mods measuring hp at the rear wheel. It really is invaluable to your colleagues who are interested in purchasing performance mods. It also helps you figure out which companies are trying to sell you a line of BS. And from what I have seen and read regarding improvements to our high-end cars, there is too much BS out there.
 

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Hello everyone
I just traded my 04 m3 for a 07 m5, love the car, but as a speed junky love to get more accelaration out of this car. I'm very new to this whole aftermarket upgrades stuff. As of last week dinan did not have a mod chip to remove the govenor, however just this past friday I was racing a porsche turbo and I reached 165mph before my radar detector (valentine1) started to go crazy. Has anyone tried to go higher on the stock m5. Dinan recommends differential upgrade and the full body throttle!!!!? I would like to get some feedback if anyone has done any of them.
I will post some video and pictures later....
 

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This is a great thread in that we can try to be objective about the gains with aftermarket modifications. I made so many mods over the years on Porsches and was often disappointed and mods almost always hurt resale, forget getting back out what you have in it. I'm trying hard to be satisfied with the stock performance of my M5 but if someone can prove X amount of gain for X amount of $, I'm all in.
 

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Discussion Starter #28
Enzom said:
I was fortunate enough to be able to dyno my C5 Z06 before and after certain mods. We ran a baseline of 351 rwhp. After a cool-down, we put on a GHL cat-back exhaust and picked up 11 rwhp. Then we put on a Haltech "sidewinder" intake and picked up another 4 rwhp. So I picked up 15 rwhp through those mods, as measured on the dyno (SAE corrected). Same day, same dyno.

I ultimately went back to the same shop and installed TPIS headers, Random Tech cats, a 160 degree t-stat, and had the computer re-programmed through what is known as "LS1-edit". Although I did not run a baseline before this last batch of work, car ultimately put down 392 rwhp (26rwhp peak improvement) with those mods on the same dyno.

Because so many C5 Z06 owners modify their cars and run baseline dynos, there was a fair amount of data to compare on the corvette boards. So people were not stuck relying on the bogus claims of the companies that made these pieces. And because there was so much data out there, it probably kept these companies more honest than they otherwise would have been.

The point here is that guys who mod their cars should really try to get proper SAE corrected before and after dyno mods measuring hp at the rear wheel. It really is invaluable to your colleagues who are interested in purchasing performance mods. It also helps you figure out which companies are trying to sell you a line of BS. And from what I have seen and read regarding improvements to our high-end cars, there is too much BS out there.
Hail, Bless you, you da man...etc...

What you're saying is absolutely, positively the ONLY way you can really evaluate performance mods to increase HP. SAE corrected dyno results for rwhp from a reputable shop actually gives you a number so you can see what your getting for your money. It is very tough to dyno this car though - the gearing and the airflow requirements make real dyno charts on the E60 M5 pretty rare. It would be great to see some before/after charts though.

I did my best to get some data on the Dinan 3.91 differential:

http://www.m5board.com/vbulletin/showthread.php?t=82994&highlight=dinan+differential

A dyno won't do any good there, but I'll bet it gives you performance equivalent to 30 rwhp.
 

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True. But just an easy comparison, and when you do it from both difections you eliminate strong winds that works against / for the performance.

MortenDK said:
There's wind resistance too Gustav, which plays a huge role.
 

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M5thusiast said:
As of last week dinan did not have a mod chip to remove the govenor, however just this past friday I was racing a porsche turbo and I reached 165mph before my radar detector (valentine1) started to go crazy. Has anyone tried to go higher on the stock m5. Dinan recommends differential upgrade and the full body throttle!!!!? I would like to get some feedback if anyone has done any of them.
I will post some video and pictures later....
At the NY meet at Jones Beach, I had my stock M5 up to 172mph in 6th gear.
Not sure it the limiter is only active in 7th?cherrsagai
 

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What happened to the Dinan throttle bodies they are now off the website?
 

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Racing Dynamics ECU upgrade?????

On the RD web site they offer a ECU upgrade that increases HP to 530 for $2200. Has anyone purchased this from RD?
 

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Well guys, i am going to be the new sponsor on this board next month. I have some goodies for the Nor Cal market and we will detail this once I get approval from the board.
I have couple of videos, dyno charts available. Hopefully i can upload most of the data tomorrow.
 

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G-Power in Germany offer a 620hp 5.5l conversion that they claim does 0-100kph in 4.0 seconds and 0-200kph in 11.5 seconds. Not shabby as far as the performance goes but the whole package including suspension and brakes costs more than a new M5. Some people just have too much money to spend and chase up the prices to silly levels.
Once BMW themselves offer a 5.5 or 6.0l then we can REALLY start to go places without spending crazy money!!
 

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Wolverine said:
Hail, Bless you, you da man...etc...

What you're saying is absolutely, positively the ONLY way you can really evaluate performance mods to increase HP. SAE corrected dyno results for rwhp from a reputable shop actually gives you a number so you can see what your getting for your money. It is very tough to dyno this car though - the gearing and the airflow requirements make real dyno charts on the E60 M5 pretty rare. It would be great to see some before/after charts though.

I did my best to get some data on the Dinan 3.91 differential:

http://www.m5board.com/vbulletin/showthread.php?t=82994&highlight=dinan+differential

A dyno won't do any good there, but I'll bet it gives you performance equivalent to 30 rwhp.
Thanks.

Your tests show a definite improvement. And if the M5 is as hard to dyno as I have been reading, it may be the only way of really demonstrating a performance improvement (other than going to a drag strip). BTW, I always thought that going with a higher ratio rear end will actually reduce your rwhp marginally but increase performance. Not sure whether the reduction in measured rwhp is correct, but that is my recollection from the research I did when I was considering changing the rear in my Z06.
 
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