MN80Vette

My old dual exhaust system didn’t fit my new Keisler RS500 transmission and cross member. That gave me the opportunity to upgrade my exhaust system to a 2.5” mandrel bent system. However, other mods to my ’80 depleted my Corvette funds I had saved up. My exhaust budget was very limited, so I decided to build my own from universal parts. I built a true dual exhaust system with universal mandrel-bent parts and Magnaflow from Summit and eBay.

(BTW, I chose Magnaflows vs. Flowmaster or other baffled mufflers to get rid of the drone we previously had, and to quiet down the interior and still keep a deep rumble.)

I started with a pair of Hedman 18804 header extenders to bring the pipes in from the full length ceramic coated headers from the previous exhaust system to area between the transmission and floor. The headers are pointed downward, so I had to cut a wedged a few inches behind the header flange from the top down, bend it up, and weld it closed to make the pipes parallel to the ground.



The header extenders fit perfectly to a Summit universal X-pipe kit welded with a pair of couplers. I welded some hangars to the back end of the X-pipe and hung it from bolts on the rear cross member.



Then I added a pair of flanges so I can remove the rear half of the system to work on stuff behind the cross members. The flanges and a short piece of straight pipe extended back to the end of a pair of 45 degree bends. The first pair of 45’s are angled up and attached to a second pair of 45’s. The back ends of the second pair of 45’s were cut short and welded to the Magnaflow mufflers.



I finished with a pair of hangars welded to the mufflers a pair of polished stainless down-turn tips.

Here are another picture of almost the whole system.



I will record and post a video with sound, but I need to get my video camera back from our daughter and son-in-law. (Getting videos of our granddaughter takes priority over our Corvette.)

MN80Vette

I plan to wrap the pipes from the header flanges to the X-pipe kit to reduce the radiant heat transfer to the floor.

cviola2005

That looks great! I like it. What was the total cost?

MN80Vette

The total cost of parts and materials was about $600 including all the parts listed above plus miscellaneous hangars, couplers, welding wire, gas, etc. You can save some $$ by using a universal H-pipe instead of an C-pipe and less expensive mufflers.

Add another $300-$500 to have an exhaust shop fit and install it. I am blessed with lots of tools including a 220V welder, chop saw, angle grinder, etc. and a big garage with a 4-post, so the total cost of my system was somewhat <$1000.

I've driven my '80 a bit with the new exhaust. We really like it. For us, it has a good balance between sound and performance. It has a deep, subtle sound without any drone at any rpm.

I will post a video with sound when I have one, after I either get my video camera back or borrow another with good soudn.

bucky katt

it looks great! being a Corvette neophyte, please excuse the dumb question. that blue rod, i'm assuming that is a traction aid?

Gordonm

Looks great. I like to see really nice home built stuff. Save a few dollars also. Looking forward to a video.

MN80Vette

The blue rod with heim joints is a homemade IRS traction bar. I had a bad wheel hop problem with the higher hp and torque of a well-tuned GM Performance 350 HO crate engine. The rear end would load and unload under sudden high torque (i.e., rapid launch) situations. The preloaded rod from the batwing to the rear crossmember prevents the load-unload cycles that caused the wheel hop.

marshal135

Absolutely beautiful work a true surgeon with a welder/bender.
I only wish I had the stuff to do work that clean.
If my underside looked that clean I'd lay on my creeper for extended periods of time and admire my undercarriage
Again nice work, wish I was closer to MN for some pointers.
Marshal

Phil Zell

Very sanitary installation, I am like GordonM, I like the home made option when it is done as well as this

pawpaws toy

Nice work! I like the extra flanges you did to remove the X-pipe.

HeavyMetalHawk

I Wish to have the ability to do that my self

bucky katt

is it aluminum or some kind of steel? i'm a decent machinist and fabricator and it looks like something i could do in an afternoon. does it affect ride quality or handling at all during normal driving?

RS69

Very nice work.

7t2vette

Did it stop the wheel hop? I need to fix that issue with my car, I never had it until I swapped out the auto for a TKO600 5spd.

MN80Vette

The traction bar in the rear does it's job during hard acceleration by preventing wheel hop. I bought the heim ends and rod as a package online somewhere, but you can buy the heim ends and buy or make the rod separately.

Yes, it stopped wheel hop completely with no other change. One made from a rod and heim joints is a lot better looking than the heavy duty one you can buy. I don't know if these are still available:

7t2vette

I actually had one of those SSm traction bars, but I sold it because I didn't like how big it was. This was a few years ago before I even had the wheel hop issue. I think I might just buy the VB&P traction bar, which is similar to what you have. Thanks for the feedback.

MN80Vette

Here is a short video with the sound of my '80 accelerating with full length headers going to 2 1/2" mandrel bent pipes with an X-pipe and Magnaflow mufflers.



I think the X-pipe mellows and evens out the exhaust sound regardless of what mufflers you use. Flowmaster bigots (especially Tim H) will argue, ridicule, and denigrate Magnaflows, but for me, Magnaflows sound good without being overbearing.