C5 Z06 180 degree header build thread

[Tinman]

I should start with an explanation of what 180 degree headers are to those who are not familiar with them. We all know that muscle car sound, as awesome as it may be it is created by uneven exhaust pulses through the collectors of typical American V8 engines, for that matter all American V8s except for the Latest Mustang GT350 and GT350R which use a flat plane crankshaft. If you look at the firing order of an LS for example, 18726543, you can see there are double stacked pulses in one bank as a pulse is skipped in the opposing bank. This gives the rumble we are all familiar with. By rearranging the primary header pipes in the collectors, 180 degree headers can space the exhaust pulses in even increments. This changes the sound to that of exotic flat plane crankshaft V8s. To make this happen, two primaries from one bank share the same collector as two primaries from the opposing bank. And the other two from each bank enter into the other collector. In all V8s I am familiar with, it is the center two from one bank and the outer two from the other bank in one collector and vice versa. Due to having to have four of the primary pipes cross sides, packaging 180 degree headers is impossible in most cars unless the primaries are made to a length way longer than optimal. Unless the engine is rear mounted or you can completely ditch the passenger seat, there is no option for 180 degree headers.

 

Exhaust note, in many cases is more important to me than what a car looks like. Graciously sculpted panels and the perfectly detailed paint applied to them can certainly entertain my eyes for hours. But when the ignition switch is turned and the pipes fire off with a harmony that pleases the ears, that's when the true appreciation of an automotive creation wins my heart.

 

I first heard the exotic music of 180 degree headers at of all places, the redneck festival that was Columbus Motor Speedway. There was a single late model stock car in a field of 20 or so racing in the A main feature race rocking the pipes that transformed the muscle of the small block Chevrolet under it's hood into a symphony of audible perfection. I took notice and never forgot that wonderful noise. 25 years later I built a set of 180 degree headers for my Howe TA2 chassis. It was not the easy route but it was possible so it had to be done. I had to have that sound for myself!

 

http://i157.photobucket.com/albums/t55/tinman_015/811C2396-9455-4AE0-B0B1-B711AFAC4F43-Copy.jpg

 

http://i157.photobucket.com/albums/t55/tinman_015/8558981A-320B-4320-9698-8153BC375F8C-Copy.jpg

 

http://i157.photobucket.com/albums/t55/tinman_015/CB53EA9D-3EA9-4F67-A6E2-D48E4D31B50C-Copy.jpg

 

http://i157.photobucket.com/albums/t55/tinman_015/F925D1DE-61F6-4216-B399-3ED0EFBAB5B7.jpg

 

 

Now, I have a C5 Z06 in my possession. Because the transmission is located at the rear, I figured I could make the same thing happen in but under it. Without a transmission in the way, the collectors could be placed where it typically is found in most cars.

[Tinman]

I decided to use 1 3/4" primaries due to tight packaging and my target primary length is 38". Longer than most headers but this will be a road course car and torque out of the corner is more important than dyno numbers. First step, locate the collectors in the tunnel. I made a little jig that allowed me to slide them fore and aft to get all the tubes where they need to go yet keep them as short as possible, 38" is a long way when crossing side to side.

 

http://i157.photobucket.com/albums/t55/tinman_015/IMG_1795.jpg

 

http://i157.photobucket.com/albums/t55/tinman_015/IMG_1797.jpg

 

http://i157.photobucket.com/albums/t55/tinman_015/IMG_1798.jpg

[Not Brian]

That sounds crazy! Are those collectors welded to those braces? Also, holy beard man..

[Tinman]

To make as much room as possible, I ground the bellhousing cover exhaust bracket bosses off and countersunk the mounting bolt holes and used flathead allen bolts from https://www.mcmaster.com/#

 

http://i157.photobucket.com/albums/t55/tinman_015/IMG_1825.jpg

 

http://i157.photobucket.com/albums/t55/tinman_015/IMG_1824.jpg

[Tinman]

That sounds crazy! Are those collectors welded to those braces? Also, holy beard man..

 

The brace is just a jig to locate the collectors. New hangers will be made to support the forward section of the exhaust.

 

Yea, the beard damn near got sucked down the throttle body. Need to tie that fucker up before it catches fire when welding.

[Tinman]

Next step, driver side primary routing. Cylinders 1,3,5,and 7 will enter the top of the collectors. 1 and 7 on the driver side and 3 and 5 into the passenger side. Afterwards the passenger side cylinders will enter the collectors. 4 and 6 to the driver side and 2 and 8 into the passenger side.

 

http://i157.photobucket.com/albums/t55/tinman_015/IMG_1842.jpg

 

http://i157.photobucket.com/albums/t55/tinman_015/IMG_1844.jpg

 

http://i157.photobucket.com/albums/t55/tinman_015/IMG_1845.jpg

 

http://i157.photobucket.com/albums/t55/tinman_015/IMG_1847.jpg

 

Damn! Failure #1. With this configuration the #3 primary length can not be kept at 38"... Version 1.2 to follow.

[AudiOn19s]

I distinctly remember when Sterling Marlin showed up in the mid 90's at Daytona with these headers and it was the talk of the 500 that year. Car sounded awesome and if memory serves he even won that year.

 

Excited to continue to follow this.

[RedRocket1647545505]

I always wanted to do this when I had my C5Z, but, I had neither the money nor the skill to complete the task. This + lightweight, high-revving V8 + Lightweight drivetrain = Standing by with dick in hand...

[MrMeanGreen]

Damn Matt, I noticed the beard first

 

The car does sound amazing, though.

[POS VETT]

Matt,

 

I like the idea and the noises generated very much.

 

One thing that comes up in my mind is thermal insulation. The tunnel area, for some reasons, transfers a significant amount of heat into the cabin. The exact cause is unknown to me, but I think it was from the convection from the engine bay and then was aggravated by the two exhaust pipes under the tunnel plate. With increased combined surface area of four primaries in each side, I suspect there would be a significant increase in heat transferred into the cabin.

 

By how much is ground clearance reduced by stacking the primary pipes in such fashion? Does the lowest point of the collectors still sit above the frame rails? Would a "tri-Y" design simplify and reduce the plumbing while keeping the same objective?

[cstmg8]

Awesome, can't wait to see/hear the end result.

 

Sent from my XT1585 using Tapatalk

[zeitgeist57]

Dude...that sounds AWESOME! Chevy SB2 with a Ford 4-speed?

[Mallard]

Nice work, can't wait to hear it!

 

Sent from my SM-G925V using Tapatalk

[Tinman]

I distinctly remember when Sterling Marlin showed up in the mid 90's at Daytona with these headers and it was the talk of the 500 that year. Car sounded awesome and if memory serves he even won that year.

 

Excited to continue to follow this.

 

I remember that as well. Not sure how well they would do with long primaries at the 9000+ RPM they spin at now. Would be awesome to hear a full field of 43 cars with 180 degree headers screaming down the front stretch of a super speedway.

[Tinman]

Damn Matt, I noticed the beard first

 

The car does sound amazing, though.

 

The beard is where my wizardly powers come from.

[Cordell]

Very awesome idea, I remember that Daytona 500 it was a really awesome sound. I hope you get this together so I can hear it on the Vette. I would love to have something unique like that on my Corvette.

[Tinman]

Matt,

 

I like the idea and the noises generated very much.

 

One thing that comes up in my mind is thermal insulation. The tunnel area, for some reasons, transfers a significant amount of heat into the cabin. The exact cause is unknown to me, but I think it was from the convection from the engine bay and then was aggravated by the two exhaust pipes under the tunnel plate. With increased combined surface area of four primaries in each side, I suspect there would be a significant increase in heat transferred into the cabin.

 

By how much is ground clearance reduced by stacking the primary pipes in such fashion? Does the lowest point of the collectors still sit above the frame rails? Would a "tri-Y" design simplify and reduce the plumbing while keeping the same objective?

 

Ever since I purchased it I have been reading on the Corvette forums about the tunnel heat issue. These have a similar surface area to a set of longtubes so I'm not too concerned with heat, if I do have problems cooking the interior I will look into some shielding and insulation.

 

Ground clearance is not a problem at the collectors, they are higher than the floorboards. I am having issues where the primaries wrap around the bellhousing to block mating area and the #5 tube will probably end up 1/2" lower than the oil pan. I will also run into issues with the #6 tube as it crosses under the top four, I'm guessing it will be 1/2" lower as well.

[Tinman]

Dude...that sounds AWESOME! Chevy SB2 with a Ford 4-speed?

 

Thanks. Jerico 4 speed actually.

[Tinman]

Thanks for all the compliments gentlemen.

[RyM3rC]

Very interesting project. Looking forward to some sound clips when it's finished.

[RS69]

Incredible art sound wise and design, can't wait for your finished product. Yes, you are true bearded wonder!

[Alex L.]

This is awesome! Great work, Matt.

[STEVE-O]

Can not wait to hear it when it's done, amazing work

[Tinman]

Version 1.2

 

http://i157.photobucket.com/albums/t55/tinman_015/IMG_1850.jpg

 

http://i157.photobucket.com/albums/t55/tinman_015/IMG_1852.jpg

 

http://i157.photobucket.com/albums/t55/tinman_015/IMG_1858.jpg

 

http://i157.photobucket.com/albums/t55/tinman_015/IMG_1855.jpg

 

At this point all four driver side primaries are past the pinch point and left long, trimming will be done tube by tube as they make their way towards the header flange. The bottom of the #5 tube will end up around 1/2" below the oil pan which does bother me but I knew concessions would need to be made to make it happen.

[Jelloman4571647545499]

Awesome Job, Matt. Is this Rob's?