Minibob97

Considering throwing muffler eliminators on my 85, I currently have the exhaust from an LT1 vette on it minus the cats. I'm not really satisfied with the noise, it's very quiet at idle, although it does have a nice scream at WOT. How loud should I be expecting if I throw eliminators on it without cats?

SJW

Loud. Very loud. About the only way to make it louder would be open headers. Be prepared for some nasty resonance, too.

Live well,

SJW

Minibob97

I still have the resonator on, wouldn't that help with the resonance a bit?

DrDyno

Allen Exhaust chambered muffler eliminators ...

TorchTarga94

Nope! Not much.

Remove the resonator and put an X-pipe in its place, I think you will find a happy medium here without going to a Corsa system.

Minibob97

I've been considering throwing on hi-flow cats as well because I'm kind of getting sick of the smell of no cats, how much effect would this have on the resonance/noise with just cats+res+elims?

TorchTarga94

You will have a lot of drone at cruising speed under any load (going up a slight grade, accelerating slowly, etc...)

That should get rid of the smell for a little while, but hi flow cats do not last as long as the factory LT1 and later cats. They will "burn out" faster.

TorchTarga94

Really depends on how you drive the car. Do you daily it? Do you go on long trips with it?

If so, you'll probably not care for the elims too much.

If you drive the car occasionally, as a weekend car and spirited driving through the twisties, you will love it. You also have the benefit of reduced weight and a cleaner looking rear.

Minibob97

Not a daily, more like a weekend and around town car, I'm mainly concerned that whenever I do take it out that it will be loud enough to be a cop magnet. Especially since exhaust modifications aren't legal in my state.

TorchTarga94

Hardly. Harley's and Bubba Trucks are more of a cop magnet than the muffler elims. Not any louder than a pickup with flowmasters. Our car's just tend to produce a heinous drone due the short exhaust system and cabin acoustics. Not so loud on the outside of the car.

94corvetteC4

I just did the muffler eliminator. Not loud at all and I don't care much for the sound. As stated above it sounds like a truck with Flowmaster mufflers. I have no drone driving normal. I do get a very small amount in 5th and 6th gear at very low RPM, 1k to about 1300 under load. My car is never that low under normal driving conditions I just took it that low the day I removed the mufflers to see if their is any drone from idle rpm on up in all gears.

My plan is for longtube headers and MagnaFlow cat back system after I get my car back from being painted.

TorchTarga94

You will have about the same amount of drone as Muffler Eliminators with the Magnaflow 16837 system. I had that cat back system on my car for two years.

TorchTarga94

If you want a completley drone free here is your options:

-Completley stock LT1 system

-Long Tubes with stock LT1 system (might be the best sounding out of everything, IMO)

-Corsa

-Using C6 NPP dual mode vacuum controlled flapper valves in an aftermarket catback of your choice. A few have done it in this forum with good success but you have to have good fabricating skills and patience to source the parts.

The Magnaflow 16837 system is of high quality. I had no issues with it, and drone usually wasn't an issue. But it does drone, especially in 6th gear at low RPM just like the eliminators. The Corsa system I have now, even with the resonator removed, is very loud! But surprisingly not an ounce of drone.

DrDyno

DanielRicany

Louder than a group of Harleys. I can attest for that. I drove past a group of loud loud LOUD Harleys and they looked over at me shocked. When I was next to them I couldn't even hear them, only my car. I has a similar set up that you want, minus the resonators.

It was too loud and had a lot of drone. I had to throw some mufflers on it because it was ridiculous. It was the best exhaust sound that I have ever heard though, but there was way to much drone.

94corvetteC4

That's the system I am looking into. I read that it's not a true duel exhaust. Supposedly the two 3" pipes going into the resonator become one 4" pipe then goes back to two 3" pipes when exiting the resonator. I also read that the pipes are ruffley 2.25" where they enter the mufflers.

The system sounds great but for the investment I plan on making I don't want any restrictions that sacrifice horse power.

TorchTarga94

That is correct on the resonator. The pipe reduced to 2.5" where the pipe clamps to the muffler can not 2.25". The stock system necks down to 2.25" which is still plenty.

Longtubes going into the stock system is a great system for not only drone control but also bang for the buck. I had no cats, a 3" X-Pipe In Lieu of the resonator, and factory mufflers and it sounded fantastic. No drone at all and a mean growl. Just stunk too bad for me, especially in parking garages. Would get all over your clothes.

skullandbones

Did you take the cats off? If so why? What will you do for emissions testing?

I was going to say, mine sounds great with cats and just resonator. But that won't mean much as the cats probably count for a lot of the noise reduction. I know it does in other cars setups so it must be similar in the vettes.

WEK.

canuck buick

I have the same set up on my 89 vert. With top down its not bad, top up I don't like it. Very rarily drive top up though.

0Magna_Flow

If you do eliminate mufflers, you may want to think about running a resonated X. It will help cut down on the drone and keep it from getting too loud. Ours is quite popular among owners doing custom setups.