Jump to content

Welcome to Nissan GT-R Heritage
Register now to gain access to all of our features. Once registered and logged in, you will be able to create topics, post replies to existing threads, give reputation to your fellow members, get your own private messenger, post status updates, manage your profile and so much more. If you already have an account, login here - otherwise create an account for free today!
Photo

My New "MEGADump" midpipe

- - - - -

  • Please log in to reply
9 replies to this topic

#1
240Z TwinTurbo

240Z TwinTurbo

    Stage 2 Member

  • Member
  • 211 posts
  • Joined 06-February 14
  • LocationCharlotte, North Carolina

I don't start too many threads on this forum, but thought I would share.  I had contemplated fabricating a 4" exhaust for my GTR, but then decided to go forward with a design I had in my head for some time regarding a new midpipe.  It's not a new concept to run a dump off the midpipe and I have seen others do the same with either electric valves or wastegates.  However, I wanted the dump to be the primary exhaust flow path and have the bypass portion be the stock routed exhaust.  I figured if I was going to run a dump I should either go big or go home. 

 

I removed my Cobb midpipe and used it to create the jig as shown below.

 

Jig6.JPG

 

 

I next started fabricating the new midpipe, which is two 3.0" primaries that merge into a 3.5" merge collector and then transition to a 4" tube.  I added some bullet mufflers because I wanted to somewhat tame the noise prior to the dump.

 

Fab3.JPG

 

 

I next added the flex sections followed by the merge collector.  You can also see the 3.5" to 4.0" transition on the outlet of the merge collector.  Unfortunately, the merge collector I ordered was too long so I sacrificed the collector on the Cobb midpipe for the new design.  I'll just rework the Cobb midpipe to add in the longer merge collector.

 

Fab6.JPG

 

 

The next task was to integrate the 4.0" piece that came with the http://www.loudvalves.com, which is a 4.0" pipe with a 4.0" Y-merge.  You can see from the pic below that after the 4.0" Y-merge I use a 4.0" to 3.5" transition to allow me to connect to the 3.5" 2-bolt exhaust flange.  You can also see in the pic below the massive 4.0" boost actuated dump valve.

 

Fab9.JPG

Fab8.JPG

 

 

I next tacked together the 3.5" pipe to the 3.5" 2-bolt exhaust flange and then guaranteed that it bolted to the car with no fitment or clearance issues.

 

Fab16.JPG

Fab12.JPG

Fab11.JPG

Fab17.JPG

Fab19.JPG

Fab22.JPG

 

 

The final step was to weld the valve to the midpipe and weld the turndown to the valve.

 

Finished2.JPG

Finished1.JPG

Finished3.JPG

Finished4.JPG

 

 

I was able to take the car to the track Friday and improved on my previous time from before, which was a 10.95@128.66.  Unfortunately, I did not get a chance to run it with valve closed, which I hope to do this Friday.

 

Run3.JPG

 

 

It is definitely LAF inside the car, but based on the video below a lot more tame on the outside vs what I thought.  Overall I am happy with the new midpipe as well as the results and the final item is to hook up the valve to a Mac 3-way solenoid in line with a 10psi Hobbs switch so I can cut this on and off.  The Hobbs switch is because the valve starts cracking at ~2psi so I want it to open much later.  Below is a link to one of my runs....10.85@129.4.

 

http://www.eng.famu....es_vs_Vette.mp4


Edited by 240Z TwinTurbo, 28 August 2017 - 09:00 AM.

  • Tim, ian.r, 7racer and 1 other like this

2006 EVO IX (573hp/439tq)

2009 GTR Premium

Built RB26 with no home (everything is for sale...lots of stuff)

Garrett V-band TwinScroll GTX35r Topmount Experiment
Garrett V-band TwinScroll GTX3576r, Curt Brown 10:1 2L, R2's, 110octane, 573hp/439tq


#2
Tim

Tim

    FYI Gators eat the bones

  • OEM Member
  • 8,705 posts
  • Joined 06-December 12
  • LocationBlue water and White Sandy Beaches
That is cool dude and your right it really isn't to loud outside the car. Nice work!!
  • 240Z TwinTurbo likes this
post-273-0-31146100-1438786356.jpg

#3
240Z TwinTurbo

240Z TwinTurbo

    Stage 2 Member

  • Member
  • 211 posts
  • Joined 06-February 14
  • LocationCharlotte, North Carolina

I was able to install the MAC valve, but have yet to hook up the 10psi Hobbs switch.  With the valve hooked directly to a boost source it starts cracking at ~2psi, which is annoying for everyday driving.  Integrating the MAC valve allows me to turn the valve on and off and with the Hobbs switch in series with the MAC valve it won't open until 10psi.  Due to packaging I will weld a flange to the bottom of the upper IC pipe and drill/tap 1/8" NPT for the Hobbs switch, which I hope to complete this weekend.

 

MAC_1.JPG

MAC_2.JPG

MAC_3.JPG


Edited by 240Z TwinTurbo, 19 September 2017 - 09:13 AM.

  • Tim, 7racer and BAZ007 like this

2006 EVO IX (573hp/439tq)

2009 GTR Premium

Built RB26 with no home (everything is for sale...lots of stuff)

Garrett V-band TwinScroll GTX35r Topmount Experiment
Garrett V-band TwinScroll GTX3576r, Curt Brown 10:1 2L, R2's, 110octane, 573hp/439tq


#4
gtrguyinaz

gtrguyinaz

    Stock

  • Member
  • Pip
  • 46 posts
  • Joined 26-April 17
  • LocationEast Valley, Phoenix

The most wild and wicked Mid Pipe ever.............

Great welding skills , concept is great but dump at 2 PSI  ????????


  • Tim likes this

#5
240Z TwinTurbo

240Z TwinTurbo

    Stage 2 Member

  • Member
  • 211 posts
  • Joined 06-February 14
  • LocationCharlotte, North Carolina

The most wild and wicked Mid Pipe ever.............

Great welding skills , concept is great but dump at 2 PSI  ????????

 

Thanks for the feedback, but if you look at post #3 I can turn the dump valve on & off with the MAC Valve and when on, it opens at 10psi because of the Hobbs Switch.  Therefore, no longer does it crack open at 2psi.


Edited by 240Z TwinTurbo, 10 October 2017 - 05:22 PM.

  • 7racer likes this

2006 EVO IX (573hp/439tq)

2009 GTR Premium

Built RB26 with no home (everything is for sale...lots of stuff)

Garrett V-band TwinScroll GTX35r Topmount Experiment
Garrett V-band TwinScroll GTX3576r, Curt Brown 10:1 2L, R2's, 110octane, 573hp/439tq


#6
240Z TwinTurbo

240Z TwinTurbo

    Stage 2 Member

  • Member
  • 211 posts
  • Joined 06-February 14
  • LocationCharlotte, North Carolina

I finally finished wiring the Mac Valve along with the Hobbs switch for the exhaust dump.

 

Wired from the solenoid to the Hobbs switch and covered the wire in some nice black loom.

wiring5.jpg

 

 

Connected to the Hobbs switch

wiring4.jpg

 

There is a great place to run the wiring harness through the firewall under the access panel for the brake booster.  Just remove the OEM plug and I inserted a grommet to my specs.

wiring3.jpg

 

And from the inside of the car.

wiring2.jpg

 

And where I mounted a low profile switch from Discount Auto.

wiring1.jpg

 

Finally, how I ran power to the MAC Valve.

wiring6.jpg


  • Tim, 7racer and shawnhayes like this

2006 EVO IX (573hp/439tq)

2009 GTR Premium

Built RB26 with no home (everything is for sale...lots of stuff)

Garrett V-band TwinScroll GTX35r Topmount Experiment
Garrett V-band TwinScroll GTX3576r, Curt Brown 10:1 2L, R2's, 110octane, 573hp/439tq


#7
shawnhayes

shawnhayes

    Stage 4 Member

  • OEM Member
  • 4,773 posts
  • Joined 11-September 13

Nice work...

 

Shawn



#8
240Z TwinTurbo

240Z TwinTurbo

    Stage 2 Member

  • Member
  • 211 posts
  • Joined 06-February 14
  • LocationCharlotte, North Carolina

Nice work...

 

Shawn

 

Thanks...it's LOUD in the car, but I like that I can turn it off.


  • Tim and 7racer like this

2006 EVO IX (573hp/439tq)

2009 GTR Premium

Built RB26 with no home (everything is for sale...lots of stuff)

Garrett V-band TwinScroll GTX35r Topmount Experiment
Garrett V-band TwinScroll GTX3576r, Curt Brown 10:1 2L, R2's, 110octane, 573hp/439tq


#9
GDZ1LLAH

GDZ1LLAH

    Stock

  • Member
  • Pip
  • 4 posts
  • Joined 18-April 16

AWESOME!  I love it when skilled people can make exactly what they want.  Very cool design



#10
240Z TwinTurbo

240Z TwinTurbo

    Stage 2 Member

  • Member
  • 211 posts
  • Joined 06-February 14
  • LocationCharlotte, North Carolina

AWESOME!  I love it when skilled people can make exactly what they want.  Very cool design

 

Thanks for the compliment.  I have been eyeing to add a high flow cat to the midpipe.  I have a little more than 8" of straight pipe in the area circled below, but likely have to modify the dump pipe for clearance.  Just debating on whether to spend $410 on the high flow cat (vibrant 7835) or use a cheaper standard 100 cel cat for $110.

 

AddCAT1.jpg


2006 EVO IX (573hp/439tq)

2009 GTR Premium

Built RB26 with no home (everything is for sale...lots of stuff)

Garrett V-band TwinScroll GTX35r Topmount Experiment
Garrett V-band TwinScroll GTX3576r, Curt Brown 10:1 2L, R2's, 110octane, 573hp/439tq





0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users