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      06-25-2013, 10:11 PM   #67
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makes me wonder if i should change up my set up on my 650 kit to get even more power out of it>.....mhmmm
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      06-25-2013, 10:22 PM   #68
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How does the pipe look like? 16.5/16.5 is huge improvement!
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      06-26-2013, 02:34 AM   #69
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Quote:
Originally Posted by BESTNDA416 View Post
makes me wonder if i should change up my set up on my 650 kit to get even more power out of it>.....mhmmm
I strongly recommend that you do. The difference on my 625 kit was like night and day. And this is coming from a die hard Akra guy.

Quote:
Originally Posted by playground View Post
How does the pipe look like? 16.5/16.5 is huge improvement!
There is a pic posted earlier in this thread. Again, the 16.5/16.5 are only the peak numbers. Throughout a huge chunk of the rev range, its more like 25-30HP gains, and 20-26 TQ. That's where the gains are the most important

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Originally Posted by RingMeister01 View Post
Wow. I have to sit down.
I'm still in disbelief. lol.
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      06-26-2013, 05:59 AM   #70
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Larger diameter pipes (as this system) are ideal for SC cars that push much more volume through the exhaust than NA. Its an appropriate assumption that systems like the Akra Evo were not engineered to be paired with a SC. Though the Akra Evo is less restrictive than the stock system, it has its limitation due to diameter size. I'm not convinced that this system would be ideal for NA, as I've seen over large diameter piping cause power loss, especially on the low end on a NA motor.

Impressive to say the least!
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      06-26-2013, 07:43 AM   #71
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Originally Posted by esquire View Post
I strongly recommend that you do. The difference on my 625 kit was like night and day. And this is coming from a die hard Akra guy.



There is a pic posted earlier in this thread. Again, the 16.5/16.5 are only the peak numbers. Throughout a huge chunk of the rev range, its more like 25-30HP gains, and 20-26 TQ. That's where the gains are the most important



I'm still in disbelief. lol.
Wow... I really have to consider this x-pipe now
Thanks for the heads up. Be fine on a non-boosted M3?
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      06-26-2013, 09:44 AM   #72
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Anyone know what the price was on this x-pipe when it was first released? or total system cost?
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      06-26-2013, 10:17 AM   #73
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Cool OP. Nice looking unit. Car looks sick also. Still have a thing for Dakar Yellow since the DTMPower days and Dado's sick E36.

Quote:
Originally Posted by RingMeister01 View Post
Larger diameter pipes (as this system) are ideal for SC cars that push much more volume through the exhaust than NA. Its an appropriate assumption that systems like the Akra Evo were not engineered to be paired with a SC. Though the Akra Evo is less restrictive than the stock system, it has its limitation due to diameter size. I'm not convinced that this system would be ideal for NA, as I've seen over large diameter piping cause power loss, especially on the low end on a NA motor.

Impressive to say the least!
+1

AA built a 3" version of their system for a customer and the result was less output.
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      06-26-2013, 10:25 AM   #74
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Quote:
Originally Posted by RingMeister01 View Post
Larger diameter pipes (as this system) are ideal for SC cars that push much more volume through the exhaust than NA. Its an appropriate assumption that systems like the Akra Evo were not engineered to be paired with a SC. Though the Akra Evo is less restrictive than the stock system, it has its limitation due to diameter size. I'm not convinced that this system would be ideal for NA, as I've seen over large diameter piping cause power loss, especially on the low end on a NA motor.

Impressive to say the least!
I agree with your reservations on NA gains BUT if the numbers being put down by Malek's personal car (supposedly 400+RWHP) are true it would suggest the 2.5" ID pipes are optimized for NA as well. Its just hard to see how full exhaust + tune can give out 50-60 RWHP considering most stock cars dyno around 340 RWHP (17% loss)
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      06-26-2013, 12:23 PM   #75
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Quote:
Originally Posted by RingMeister01 View Post
Larger diameter pipes (as this system) are ideal for SC cars that push much more volume through the exhaust than NA. Its an appropriate assumption that systems like the Akra Evo were not engineered to be paired with a SC. Though the Akra Evo is less restrictive than the stock system, it has its limitation due to diameter size. I'm not convinced that this system would be ideal for NA, as I've seen over large diameter piping cause power loss, especially on the low end on a NA motor.

Impressive to say the least!
The gains seen by the MRF Engineering mid-section has very little, if any to do with the piping diameter selection. We have noticed many comments and responses with respect to system diameter and wanted to take this opportunity to dispel some misconceptions.

The Akrapovic Evolution and GT4 mid-sections are not 2.25" I.D. systems. They are 2.375". The MRF system is for the most part a 2.5" I.D. mid-section. In regards to volumetric flow and capacity, dual 2.25" pipes are more than capable of handling over 600 RWHP.

The volume of an exhaust pipe is calculated as a cylinder. To calculate the volume of a cylinder, the formula is:
V= πR² x H (in this case, H will be Length and represent the length of the exhaust system)

Known variables:
Length = 80" (length of mid-section)
Radius = Diameter/2 = 1.125"
And of course, the mathematical constant of Pi

TOTAL VOLUME = 318 (now this must be multiplied by 2 because there are 2 pipes) = 636 (for comparison sake, a single 3" exhaust which can handle 575 RWHP happily, has a total volume of 565.)

Volume of a SINGLE 3.5" exhaust: (which many of us engine builders know that its capable of handling 700 RWHP easily)

Known variables:
Length = 80" (length of mid-section)
Radius = Diameter/2 = 1.75"
Mathematical constant of Pi

TOTAL VOLUME = 769

Volume of a 2.5" I.D. mid-section (again dual pipes)
Known variables:
Length = 80" (length of mid-section)
Radius = Diameter/2 = 1.25
Mathematical constant of Pi

TOTAL VOLUME (must be multiplied by 2) = 784

Volume of Akrapovic Evolution/GT4 mid-section

Known variables:
Length = 80" (length of mid-section)
Radius = Diameter/2 = 1.1875"
Mathematical constant of Pi

TOTAL VOLUME (must be multiplied by 2) = 708

Now with all this said, the point here was not to demonstrate the differences in volume, it's only to help understand what each diamter means in regards to total volumetric capacity in the system. 2.25" dual systems are more than adequate for the 4.0L S65 M3, even when highly strung out. Now, lets make this clear, the Akrapovic is not 2.25", it is 2.375". The stock M3 mid-section is an odd size, it is somewhere between 2.375" and 2.5", it is also not 2.25". The factory mid-section has one part that is 2.25", and that is the first 2" coming off the front flange to create room for the o2 sensor bung.

Now back on topic to the MRF Velaforza mid-section..... The pipe was designed for N/A applications and we also knew and tested it on high forced induced applications to see its capabilities. As mentioned earlier in my first post, we tried larger diameter piping on S/C'd cars (3") and saw no appreciable gain, and only lost low end torque. In N/A form, the car simply did not like the 3" version.

In N/A form, comparing peak RWHP and peak RWTQ, produces 28 RWHP and 22 RWTQ over stock, and in the mid-range, produces a delta of more than 32 RWHP and 40 RWTQ. The most produced by any E9x system we are aware of.

If some are experiencing that 2.5" systems are not sufficient for their cars power output, I suggest looking at replacing your rear section exhaust system with something that retains the volumetric capacity of the mid-section, as many of the systems out there shrink down the perforated sections inside the muffler assemblies to reduce drone and unwanted frequencies. The Akrapovic rear section does a great job at maintaining this capacity.

-Malek
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Last edited by Malek@MRF; 06-26-2013 at 01:53 PM.
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      06-27-2013, 01:34 AM   #76
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Quote:
Originally Posted by playground View Post
Wow... I really have to consider this x-pipe now
Thanks for the heads up. Be fine on a non-boosted M3?
yeah. i've seen two non-boosted m3's with the MRF set up. Malek's and one other. And they are some of the most beastly m3's i've seen. no joke.

Quote:
Originally Posted by Soorena View Post
Cool OP. Nice looking unit. Car looks sick also. Still have a thing for Dakar Yellow since the DTMPower days and Dado's sick E36.
Thanks Soorena. Very kind words.
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      06-27-2013, 01:45 AM   #77
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Originally Posted by lsmkr01 View Post
Anyone know what the price was on this x-pipe when it was first released? or total system cost?
The X-pipe (midpipe, same thing) is $1999 U.S. Not sure how much the FULL system costs (mid and rear) since I don't have the full system. But I think the full system is less than 4k.
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      06-27-2013, 07:58 AM   #78
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Quote:
Originally Posted by Malek@MRF
Quote:
Originally Posted by RingMeister01 View Post
Larger diameter pipes (as this system) are ideal for SC cars that push much more volume through the exhaust than NA. Its an appropriate assumption that systems like the Akra Evo were not engineered to be paired with a SC. Though the Akra Evo is less restrictive than the stock system, it has its limitation due to diameter size. I'm not convinced that this system would be ideal for NA, as I've seen over large diameter piping cause power loss, especially on the low end on a NA motor.

Impressive to say the least!
The gains seen by the MRF Engineering mid-section has very little, if any to do with the piping diameter selection. We have noticed many comments and responses with respect to system diameter and wanted to take this opportunity to dispel some misconceptions.

The Akrapovic Evolution and GT4 mid-sections are not 2.25" I.D. systems. They are 2.375". The MRF system is for the most part a 2.5" I.D. mid-section. In regards to volumetric flow and capacity, dual 2.25" pipes are more than capable of handling over 600 RWHP.

The volume of an exhaust pipe is calculated as a cylinder. To calculate the volume of a cylinder, the formula is:
V= πR x H (in this case, H will be Length and represent the length of the exhaust system)

Known variables:
Length = 80" (length of mid-section)
Radius = Diameter/2 = 1.125"
And of course, the mathematical constant of Pi

TOTAL VOLUME = 318 (now this must be multiplied by 2 because there are 2 pipes) = 636 (for comparison sake, a single 3" exhaust which can handle 575 RWHP happily, has a total volume of 565.)

Volume of a SINGLE 3.5" exhaust: (which many of us engine builders know that its capable of handling 700 RWHP easily)

Known variables:
Length = 80" (length of mid-section)
Radius = Diameter/2 = 1.75"
Mathematical constant of Pi

TOTAL VOLUME = 769

Volume of a 2.5" I.D. mid-section (again dual pipes)
Known variables:
Length = 80" (length of mid-section)
Radius = Diameter/2 = 1.25
Mathematical constant of Pi

TOTAL VOLUME (must be multiplied by 2) = 784

Volume of Akrapovic Evolution/GT4 mid-section

Known variables:
Length = 80" (length of mid-section)
Radius = Diameter/2 = 1.1875"
Mathematical constant of Pi

TOTAL VOLUME (must be multiplied by 2) = 708

Now with all this said, the point here was not to demonstrate the differences in volume, it's only to help understand what each diamter means in regards to total volumetric capacity in the system. 2.25" dual systems are more than adequate for the 4.0L S65 M3, even when highly strung out. Now, lets make this clear, the Akrapovic is not 2.25", it is 2.375". The stock M3 mid-section is an odd size, it is somewhere between 2.375" and 2.5", it is also not 2.25". The factory mid-section has one part that is 2.25", and that is the first 2" coming off the front flange to create room for the o2 sensor bung.

Now back on topic to the MRF Velaforza mid-section..... The pipe was designed for N/A applications and we also knew and tested it on high forced induced applications to see its capabilities. As mentioned earlier in my first post, we tried larger diameter piping on S/C'd cars (3") and saw no appreciable gain, and only lost low end torque. In N/A form, the car simply did not like the 3" version.

In N/A form, comparing peak RWHP and peak RWTQ, produces 28 RWHP and 22 RWTQ over stock, and in the mid-range, produces a delta of more than 32 RWHP and 40 RWTQ. The most produced by any E9x system we are aware of.

If some are experiencing that 2.5" systems are not sufficient for their cars power output, I suggest looking at replacing your rear section exhaust system with something that retains the volumetric capacity of the mid-section, as many of the systems out there shrink down the perforated sections inside the muffler assemblies to reduce drone and unwanted frequencies. The Akrapovic rear section does a great job at maintaining this capacity.

-Malek
Product of the year. Great info, thank you.
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      06-29-2013, 09:46 AM   #79
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I have to admit that I didn't see these top end gains coming esquire.

The largest benefit I saw with the data available to me before making the purchase back jn Oct was how much low end torque increases with this x-pipe. Like I've said before, with the blower and stock exhaust, WOT acceleration at low RPM was still disappointing to me.

After installation of the exhaust, the difference in low-end grunt was so significant that it rendered my "power" button completely useless as going WOT would just spin the tires. Too much throttle sensitivity and too much torque and not enough tire. Oh well disabling the power button is an easy solution.

The gains up top are just gravy.
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      06-29-2013, 03:37 PM   #80
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Quote:
Originally Posted by esquire View Post
The graphs are temperature and humidity corrected. If you've read my posts throughout, I don't argue that temperature and humidity could not have played a role here, in fact I admit they can. My point is that after STD/SAE correction, what little hasn't been corrected for, cannot explain the size of the gains.

One thing you don't distinguish above is whether the 20-30 whp differences you say on bubu's car were while viewing uncorrected or corrected graphs. I personally have never seen 20-30 whp differentials on a corrected graph, if you're talking about the exact same car, same mods, same fuel, etc. I can certainly see those kinds of differentials happening on an uncorrected graph.


Another important factor here is that the weather conditions tugged in opposite directions. On day 1 (dynoing the Akra Midpipe), the temperature was hotter, but the Humidity was very low. On day 2, (dyoing the MRF midpipe) the temperature was cooler, but the humidity was considerably higher.

I will definitely try to get another dyno day going soon, and try to do back to back runs of the Akra and MRF (and maybe even OEM midpipes). Might be some time away though Thanks for the feedback.
Well posted.

However, there are variables that the dyno is not aware of which is the DME itself which will fluctuate the ignition timing and AFR depending on environment and adaption values.

Ignition timing can make a huge difference on it's own as many have seen.

Without logging ignition timing really the results are somewhat crude for comparisons sake.

What is also not often logged is the actual inlet temperature. Again, this directly effects AFR and ignition angle.

For a true test, these variables must be logged and shown.

Let me give you an independent example from Italy, Supersprint.

Stock E92 M3 vs Supersprint X Pipe (High Flow CATs) and Rear Exhaust

A massive +36rwhp



However, is it a completely fair test?
Well... yes and no. They are using SAE correction factors here however SAE just could not compensate enough. It corrected for the delta of 6 degC in both ambient and inlet temperature BUT could not take into account the difference in ignition timing.

Let us look a little further at the ignition timing:

Baseline run:

You can see the ignition timing (Zundung) runs at around 33deg midrange and around 28deg high rpm.



Supersprint full system Run:

Igniting timing at the higher rpm is 2 degrees higher and around the same in the midrange. After 5000rpm it is always higher than the base line run.




The temperatures were higher with the stock run and this was out of Supersprints' control. The DME decided to run slightly lower timing.

So, this amazingly higher gain in power is not just down to the exhaust system itself but the difference in temperature and eventually the amount of ignition timing. So the results even in this tightly controlled test are still slightly skewed.

Now, consider this. If the tests were done with the conditions reversed the gains would be less than they should be. I do have an example of this if anyone would like to see it.

Notice that on both tests the barometric pressure and humidity are almost equal. SAE is doing it's best but cannot compensate for what the DME is doing.
We all know that a stock car can run at least 30deg timing and even sometimes 32 if the conditions are right.

Hope this adds a new dimension to dyno testing for you guys.

Last edited by Sal@Evolve; 06-29-2013 at 04:17 PM.
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      06-29-2013, 04:04 PM   #81
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Quote:
Originally Posted by Malek@MRF View Post
Hello everyone,


1) The system utilizes a true Motorsport X merge in the pipe which is TIG welded, not MIG. ........

2) The position of the “X” is move...........

3 )I have seen quite a few people post in here regarding piping diameter. Unfortunately most of these posts are improper or misrepresentative. What is not being mentioned.............

4) The MRF system as me..........

5) 100 Cell catalysts VS. Catless. Power wise, there is almost no difference at all, especially when high quality catalysts are used. If cheap units are used, they will eventually clog and restrict flow. In many cases, cheaper systems choke up the flow when excessi.....



-Malek@MRF

Very nice Malek.
I am sure you have earned the respect of not only the members here but also sponsors/tuners/etc.

It is very nice to see finally see someone confirm the difference in X Pipes, High quality CAT's vs No CAT's and especially mentioning that unless the primary restriction of the header outlet is removed changing anything after this is not beneficial.

Agree with most of what you say.

Hopefully we will see you post more often.
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      06-29-2013, 04:12 PM   #82
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      06-29-2013, 05:43 PM   #83
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Quote:
Originally Posted by Sal@Evolve
Quote:
Originally Posted by esquire View Post
The graphs are temperature and humidity corrected. If you've read my posts throughout, I don't argue that temperature and humidity could not have played a role here, in fact I admit they can. My point is that after STD/SAE correction, what little hasn't been corrected for, cannot explain the size of the gains.

One thing you don't distinguish above is whether the 20-30 whp differences you say on bubu's car were while viewing uncorrected or corrected graphs. I personally have never seen 20-30 whp differentials on a corrected graph, if you're talking about the exact same car, same mods, same fuel, etc. I can certainly see those kinds of differentials happening on an uncorrected graph.


Another important factor here is that the weather conditions tugged in opposite directions. On day 1 (dynoing the Akra Midpipe), the temperature was hotter, but the Humidity was very low. On day 2, (dyoing the MRF midpipe) the temperature was cooler, but the humidity was considerably higher.

I will definitely try to get another dyno day going soon, and try to do back to back runs of the Akra and MRF (and maybe even OEM midpipes). Might be some time away though Thanks for the feedback.
Well posted.

However, there are variables that the dyno is not aware of which is the DME itself which will fluctuate the ignition timing and AFR depending on environment and adaption values.

Ignition timing can make a huge difference on it's own as many have seen.

Without logging ignition timing really the results are somewhat crude for comparisons sake.

What is also not often logged is the actual inlet temperature. Again, this directly effects AFR and ignition angle.

For a true test, these variables must be logged and shown.

Let me give you an independent example from Italy, Supersprint.

Stock E92 M3 vs Supersprint X Pipe (High Flow CATs) and Rear Exhaust

A massive +36rwhp



However, is it a completely fair test?
Well... yes and no. They are using SAE correction factors here however SAE just could not compensate enough. It corrected for the delta of 6 degC in both ambient and inlet temperature BUT could not take into account the difference in ignition timing.

Let us look a little further at the ignition timing:

Baseline run:

You can see the ignition timing (Zundung) runs at around 33deg midrange and around 28deg high rpm.



Supersprint full system Run:

Igniting timing at the higher rpm is 2 degrees higher and around the same in the midrange. After 5000rpm it is always higher than the base line run.




The temperatures were higher with the stock run and this was out of Supersprints' control. The DME decided to run slightly lower timing.

So, this amazingly higher gain in power is not just down to the exhaust system itself but the difference in temperature and eventually the amount of ignition timing. So the results even in this tightly controlled test are still slightly skewed.

Now, consider this. If the tests were done with the conditions reversed the gains would be less than they should be. I do have an example of this if anyone would like to see it.

Notice that on both tests the barometric pressure and humidity are almost equal. SAE is doing it's best but cannot compensate for what the DME is doing.
We all know that a stock car can run at least 30deg timing and even sometimes 32 if the conditions are right.

Hope this adds a new dimension to dyno testing for you guys.
Hey Sal

Excellent info. EAS (dynojet operator) actually logs ignition, IATs, AFRs, etc. The data is in the drf files.

So maybe esquire can post those up as well to see more info about what is going on with these 2 runs.
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      06-29-2013, 06:29 PM   #84
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Hey Sal

Excellent info. EAS (dynojet operator) actually logs ignition, IATs, AFRs, etc. The data is in the drf files.

So maybe esquire can post those up as well to see more info about what is going on with these 2 runs.
Hi.
Thats great news.
Depends if the datalink was enabled at the time.
These dyno's are becoming more and more appealing.
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      07-01-2013, 02:23 PM   #85
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Just talked to Malek@MRF today. Looks like there's been so much demand generated for his midpipe, that it's gonna go back into limited production.
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      07-01-2013, 03:21 PM   #86
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Hello everyone,

I have read this thread over in good detail and I am going to do my best to clarify and answer everyone's questions in this post. I am not going to quote every person and respond individually because I am hoping this response will help address any of those curiosities and/or questions. Let me clarify a few things about the MRF Engineering Velaforza mid-section. It is not like all the other systems that have been made for the S65B40 power plant. The system is 100% and fully engineered for the S65B40 engine and does not employ standardized procedures in its design.
Thanks for the response Malek. I don't know much about X-pipe development, but from what i can gather about your response is many (but not all) companies do the least amount of effort they can to bring an X-pipe to market. Remove cats, check for improved flow, check back pressure and manufacturer at the lowest cost and call it day. I guess there isn't much of an incentive to fully engineer an X-pipe for a single car/engine to squeeze out those last few hp/torques as the market would be very limited and you're not guaranteed additional profits.

It is good to read about the method/design/manufacturing you utilized during the R&D process of this X-pipe and it looks like it really paid off. I have major respect for shops such as yours that go out of the way to connect with the community about your products.

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Just talked to Malek@MRF today. Looks like there's been so much demand generated for his midpipe, that it's gonna go back into limited production.
That is great to hear. Wish i wasn't saving up for some major big ticket items otherwise i would definitely jump on this!
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      07-01-2013, 04:44 PM   #87
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The X-pipe (midpipe, same thing) is $1999 U.S. Not sure how much the FULL system costs (mid and rear) since I don't have the full system. But I think the full system is less than 4k.
Thanks for the information. Considering its made of SS and there are no resonators or cats on it that would add cost I hope there is some sort of group buy. Who ever made 2k the standard for any quality x-pipe should be shunned
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      07-01-2013, 04:49 PM   #88
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The X-pipe (midpipe, same thing) is $1999 U.S. Not sure how much the FULL system costs (mid and rear) since I don't have the full system. But I think the full system is less than 4k.
Thanks for the information. Considering its made of SS and there are no resonators or cats on it that would add cost I hope there is some sort of group buy. Who ever made 2k the standard for any quality x-pipe should be shunned
maybe you haven't done much exhaust shopping my friend, but 2k ends up being a bargain when you start doing your price comparisons.
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