M.A.D. Chambered Exhaust

[77vette]

The minor tweaks was nothing more than the larger aluminized pipes and the more effecient high flow cat. Sorry, if I confused you.

 

[mvftw]

Thanks, is this the exhaust system that is going for $470 on CC?
Or is that about would it cost you?

 

[70 LS1]

If anyone is interested, here is my sound clip of the LS1 with the MAD chambered exhaust.

LS1 exhaust

I love the way the chambered system is mellow at idle and wild at WOT.

 

[Cream79L82]

What I like the most about having an exhaust is the mere presence it gives you at a stop light. I live in a land that generally hasn't been ravaged by liberals yet, so I've never had any trouble with the law, even though I've got long tube headers straight back thru 2.5" pipes and dual flows. She sounds pretty let me tell ya. The only thing they'll get you for around here is noise violation... so I just idle past any cops. I'm sure you'll be pleased no matter what you decide.

 

[77vette]

That's it, mvftw....p.71 in the CC catalogue. You'll be happy with the complete system.

 

[mvftw]

The Best of Both Worlds...Since I live in a Smog State, I want true duals with xover pipe, but I need 2 cats (a waste then)... my plan is to have 2 "Test Pipes" made up, since the cats have flanges on both sides anyway...Just have to put the cats on for a week...:cool

 

[Last Ride]

I live in Springfield, IL, and I have ture duals on my car. The problem is, I don't really like the sound. It might just be the setup, but it sounds find of squirrelly even through a pair of Flowmasters. I have been looking long and hard at the chambered exhaust, but I don't know if I want to switch from stainless back to aluminum. I plan on redoing the exhaust within the next year or two with full tube headers (the shorties on there now are an improvment, but oh well. I really want to bring the LT1 I had so much trouble getting into the car to life! I don't know how much a chambered exhuast will contribute, but the true duals on there now actually shake! Would I be better off going with a cross over pipe or what?

 

[phulst]

I purchased the MAD system a year ago, and installed it on my 71 coupe.

A couple of notes:
1. It's loud. Don't expect to be subtle anymore. My car is now louder than my friend's 1966 427/425 with side pipes. At first it was louder than I would have liked, but I've grown fond of it.
2. I noticed some resonance in the rear portion of my coupe. Now, as that's a lot smaller area in a 71 than in your 78, you may not have that.
3. You may or may not need new exhaust tips. At least for my 71 I purchased new ones, as they didn't come with the kit.
4. The system was easy to install. I used a lift, as I own one. I'm sure you could do it on the floor if you needed to. I had two friends helping me, and it went FAST.

Patrick

 

[78SilvAnniv]

Bottom end torque loss...

I need to address my concerns about the bottom end torque loss I felt I had after the chambered installation.

My fears are ungrounded!

Yesterday we went to a birthday party and Kenny drove. Head snapping starts from a stop!...there is PLENTY of torque!
We have determined that it is actually my driving manner that is causing me to think I have lost torque.

With the increase in sound, I have been tentative on the go-pedal, which makes it seem to hesitate, causing me to think I have lost torque.
It appears I have just been intimidated away from actually using it. My vette is properly tuned, and Kenny says there is no need to make any adjustments, other than my driving manner.

How's that for an easy fix?
Heidi

 

[Shawn's 78]

Heidi,
That's great news! BTW - What did Kenny initially set the timing at; 6, 8, or 10 degrees BTDC? Did he do anything else to the timing before the exhaust swap?

Also, I never did ask, did you instal an "H" pipe or are going straight back from the exhaust manifolds?

Shawn

PS - Ordered my Chambered system yesterday - should be here in a week. Can't wait to remove the original (and I mean original) exhaust! :J

PSS - Don't be afraid to hammer that pedal once in a while! It keeps the blood flowing!:Roll

 

[phulst]

One thing to remember about an "H" pipe installation: it probably will come in plain carbon steel. Your chambered system will come in aluminized steel. Once you cut the aluminized system you introduce the potential of rust at the new joints. I addition, your carbon steel "H" pipe will rust out much faster than the rest of the system.

I'm not sure you'll "gain" enough from its installation to offset the shorter life you'll realize from the rust.

I also used stainless steel clamps when i installed my system, so that I could easily come back and adjust it later. I hate rust.

Patrick

 

[78SilvAnniv]

No "H" pipe.

Kenny isn't home right now for me to ask what the timing is set at. We had the carburator rebuilt this past summer and while it was off he did a tune up with wires, plugs, distributor and stuff. Whatever it was set at then, is what it is at now, and it runs great.

I am just too hesitant from a stop. Once I get rolling I don't mind putting my foot in it up to 4500rpms where the tranny shifts. This gets me up to 60mph pretty quick, and makes me smile, if I am first at the light on the hwy.

The difference between idle and then actually giving it gas to move is AWESOME, and the sound intimidated me into being softer on the pedal. Now that I know what I am doing...I can consciously change my driving manner and drive the vette like she needs to be driven, and not worry about what I "think" is happening.
Heidi

ps...good info about the rusting out "H" pipe...I think I will strike that off my 'want' list.
h

 

[gary b.]

Thanks Heidi

Heidi, thanks for your reply about ''torque loss'' (from page 1)
It makes alot of sence what you said.
I got my chambered system the other day!
Went to my local corvette shop, they wont put the chambered
on, because the cat. converter is illegal for them to remove.
Dont really want to put it on myself, but, looks like i'll have to.
Any other ideas?
Thanks again! Gary.

 

[Last Ride]

Re: Thanks Heidi

Went to my local corvette shop, they wont put the chambered
on, because the cat. converter is illegal for them to remove.
Dont really want to put it on myself, but, looks like i'll have to.
Any other ideas?
Thanks again! Gary.

Gary--
What about taking it to another shop? I am sure you can find someone to do the work. If you were closer to Central IL, I could recommend a place that supposedly does good work (No real experience yet, but the guy has a waiting list, and I am planning on mine for later this summer.) Good luck either way!

Bryan

 

[78SilvAnniv]

Try another shop!

My local muffler shop would not remove my cats, but then my local vette shop guy said he would do it. You may want to go to the smaller, independently owned shops before trying a "chain" that has lots of management and rules.

If you cannot find anyone to do this for you...you can do it yourself. It is pretty straightforward. I think the biggest item of difficulty will be removing the original exhaust system.

Installation will go easier if you can raise the vette on a lift, or at least jackstands. Just hack up the old system and get it out of there, the chambered should slip in and bolt right up to the exhaust manifold, set the hangers, tighten the clamps and you're good to go!
Heidi

 

[Bob Chadwick]

Re: Thanks Heidi

Went to my local corvette shop, they wont put the chambered
on, because the cat. converter is illegal for them to remove.

Gary,

Just be aware. If you rely on others to do your work some shops may not take cars in that have had their emissions systems modified as it could result in a fine to them.

Having said that I modified mine.

Bob

 

[gary b.]

THANK'S!

Thank You, Heidi, Brian, & Bob!
I"ll check out some more shops. I"m sure there is someone
out there that will do the deed.

I can"t wate to here my vette sound like a vette!!

 

[born2saw]

I'm not sure where in IL you are, but if you are anywhere close enought to go to Logansport, IN there is a highly recommended exhaust shop there. They only advertise "leqal" work, but I have heard through the grapevine they do very good work and some "special" jobs. They have a website Here but you may find out more via a phone call.

Let us know how it goes.