gonefishn

A friend of mine put on a set of NOS N11 mufflers (paid plenty for them) and they sounded incredible. Never heard a real set of N11 before. Sounds nothing like the "off-road" LIC version I have.

Will be checking to see if Gardner has an exact construct of the original design. If not, does anyone know of a source that manufactures a replica of the off-road exhaust?

Most likely this falls under the fate of current repro knock-offs.............go 90% of the way but fall short of being accurate

Thanks,
John

Corbrastang

Nobody reproduces the original style. We should all pitch in, buy some NOS units and send them to one of the exhaust manufacturers so that they can cut them open and reproduce them.
How did they sound compared to sidepipes??

66BBDriver

my '66 has a set of repo N11 and I don't like the sound. I am thinking of puting a set of under car chambered pipes,but I like the looks of the mufflers from the back. If we can get a better sound out of another set of N11's I will go that way. Firedog

gonefishn

They had a very unique sound not too different from the side exhaust. They had more of a "popping" sound at idle, and when the engine was reved, they had a really nice higher throaty tone. But not obnoxiously load.....just perfect. The current repros (at least the ones I have) are lower tone and quieter.

The exhaust sound was distictly clear in the car too and also at the higher tone then the current repros. I would say it was about 2x louder then the current repros.

Being basically sheet metal I would think that reconstructing them by one of the manufactures shouldn't be too expensive or difficult.

I wonder if the blueprints can be located inside or outside of GM.

John

SBR

My car has an original set of N11s on it and my other car has side exhaust and I prefer the N11s, they have that cracking sound to them and at idle it has that popping sound which made 60s Corvettes sound like no other car at the time. I still have an NOS set with the tags on them just as a spare set but I sure wish that they could be accurately reproduced because original NOS sets are getting insanely priced if you can even find a set.

66since71

I have never seen the "off road exhaust".

I always wondered if the N11's were the same as the chambered exhaust now sold by some of the parts dealers. That is, does the cambered section replace the muffler or does it replace the section of pipe from the middle cross member to the back of the differential (with a straight pipe then to replace the muffler)?

RGGregory

The N-11 was a three-baffle standard size/shape muffler in the location of the basic underbody system. The base muffle was a 5 baffle (knowledge courtesy of Noland Adam's book).

It has nothing in common with the side exhaust. My old 67 originally came with the N-11. I couldn't find NOS or suitable (to my ear) repro's, so I went with a Sweet Thunder stainless underbody chambered with 3 inch chambers...a great sound!

RGGregory

Just out of curosity (not looking to buy), how much are a set of NOS N-11's going for? My old 67 (sold last Fall) had them as an option.

Corbrastang

I am also interested to know what a set of NOS N11 mufflers go for.

tapio

I think this would be a great opportunity for the muffler companies. The EXACT repro of N11 would be just the ticket for a large number of C2 nuts.

427 Mitch

Just out of curosity (not looking to buy), how much are a set of NOS N-11's going for? My old 67 (sold last Fall) had them as an option.

In 2002, I paid $3500. for an NOS N-11 set.

Mitch

Corbrastang

WOW!!!! I had no idea they went for that much-ouch!

Well, i would say that even with the licencing fees from GM that any company that would reproduce these would stand to make a large amount of cash. Why do you think the chambered under car exhaust system is so popular?? B/C there isnt another undercar system that makes noise. I had the "off-road" reproduction mufflers and welded pipes on my car before side exhaust and you couldnt hear anything. This was when i had the 365hp cam as well.
My father ordered Corvette Central exhaust and it was even worse in terms of no noise.
Come on muffler companies, it cant be that hard. In fact, it should be easier since there are less chambers.

clint4vette

I recently purchased an anodised set of off road for my 64 fuelie from Allens. The car is quiet enough in the inside with the top off to hear the radio, but radical enough on the outside to hear the 30 30 solid cam popping off each cylinder crisply. I had Allens stock exhaust on it just prior to the off road and you couldn't hear the motor. I don't have the first hand knowledge of what original N-11 exhaust sounds like, but I sure like the way mine sound.

ctjackster

for which car ?

hey, did you ever get the starter wiring straightened out on the L89?

427 Mitch

For other car.

I had the L89 towed to LI and they had to put in a wire harness because of all my handy work.

Thanks, Mitch

ctjackster

Don't be too hard on yourself, that one was a bit of a freak accident (little heat shield falling down and causing a short in the wires, I recall). I have done WAAY more obviously stupid things when working on my stuff, and if you haven't yet slammed a hood shut while leaving a large metal tool behind on top of the aircleaner, which then causes massive damage to your hood (thankfully not on my 65) you are not yet in my league . . .

SBR

I was offered 4K for my set at BG but refused because they are getting almost impossible to find. Ask 427 Mitch how N11s sound on his car, in a word awesome!

gonefishn

Interestingly, the LH Off-road exhaust 3845735 was shown in the GM database as still available. We made a few calls and were informed that the part was not available (which I assumed would be the case).
Kind of interesting it is still in GM's database.

John

SBR

I believe that only one side was available until, ie. the 735 pipe and muffler until maybe a couple of years ago. The problem is that you still would have needed the other side which is the 736 pipe and muffler and the front pipes as well

67pete

The original underneath off-road exhaust looked exactly the same as the standard underneath exhaust with the exception that it was a welded pipe and muffler, as opposed to the clamped stock unit. It's sound was a little more throaty than the stock but, no where near to the side pipe sound(apples & oranges)!