Avanti stock exhaust

[pantera928]

Does this exhaust look stock or aftermarket for a 1980?

THanks

[Avanti83]

The down pipe off the manifolds to the mufflers looks stock but the mufflers are not. From the head pipe back it's been replaced.

[pantera928]

Just now, Avanti83 said:

The down pipe off the manifolds to the mufflers looks stock but the mufflers are not. From the head pipe back it's been replaced.

Thanks. THe car is a bit loud so i may try to quiet it down

[Gunslinger]

It's not a real Avanti unless the ground shakes under when you fire it up.

[pantera928]

1 hour ago, Gunslinger said:

It's not a real Avanti unless the ground shakes under when you fire it up.

Well, if that L48/350 had any horsepower, it might be a different story.🤣

I think it is probably the slowest car in my fleet.

[80Avanti]

I bought my 1980 Avanti in 1992 and it still had the original exhaust. The mufflers were very rusty and full of holes. I replaced them with some glasspacks that look like the mufflers on your car.

Tim

 

Edited January 25, 2022 by 80Avanti

[mfg]

This system on your Avanti is very restrictive...especially the crossover pipe that connects the "cat" to the twin mufflers....My '83 had that same system.......My '85 Avanti has a similar system, however the factory took pains to smooth out the bends in that that connector pipe, which eliminates some of the restriction.

Best solution, (in my opinion and if your State does not require an emission test on your '80 Avanti), is to replace what you have with a true dual exhaust system, as would be found on, say, a 1967 Avanti ll...It bolts right on, and relieves the engine of that back pressure in the exhaust system

That's what I did on my '83 Avanti 'everyday driver' years ago.

[pantera928]

1 hour ago, mfg said:

This system on your Avanti is very restrictive...especially the crossover pipe that connects the "cat" to the twin mufflers....My '83 had that same system.......My '85 Avanti has a similar system, however the factory took pains to smooth out the bends in that that connector pipe, which eliminates some of the restriction.

Best solution, (in my opinion and if your State does not require an emission test on your '80 Avanti), is to replace what you have with a true dual exhaust system, as would be found on, say, a 1967 Avanti ll...It bolts right on, and relieves the engine of that back pressure in the exhaust system

That's what I did on my '83 Avanti 'everyday driver' years ago.

Thanks

I had been thinking about that. My county does not care what exhaust is on my car. My 1971 Cutlass is run that way already.

Do you think any difference would be noted in power or fuel economy? Not that we buy these for their gas mileage.🤣

[Gunslinger]

Less restriction translates to more power and less back pressure which helps fuel economy.  How much depends on how efficiently the engine makes power and if you can keep your foot out of it.  It may make a noticeable difference but it could also be negligible.

The stock exhaust is probably 2” diameter tubing…move it up to a 2.5” piping for better efficiency.

[pantera928]

8 minutes ago, Gunslinger said:

Less restriction translates to more power and less back pressure which helps fuel economy.  How much depends on how efficiently the engine makes power and if you can keep your foot out of it.  It may make a noticeable difference but it could also be negligible.

The stock exhaust is probably 2” diameter tubing…move it up to a 2.5” piping for better efficiency.

Thanks. I have a local shop that does my custom work. I will talk to them

[Avanti83]

51 minutes ago, pantera928 said:

Thanks. I have a local shop that does my custom work. I will talk to them

Have them look particularly at the driver's side manifold connection. It's a bit of a b--th to fabricate.

Here's the one I did on my 74.

https://forum.studebakerdriversclub.com/forum/your-studebaker-forum/tech-talk/76100-74-avanti-sbc-t-56-2-1-2-exhaust-system-and-undercarriage 

This is the finished project with 2 1/2" pipes. Your exhaust will be 2" so you'll need to find 2 1/2" manifolds. They are available aftermarket for reasonable dollars. Look for mid-60's Corvette manifolds.

 

Edited January 26, 2022 by Avanti83

[Jim78]

11 hours ago, pantera928 said:

Thanks. I have a local shop that does my custom work. I will talk to them

Don Simmons at Silvertone Exhaust Systems has been doing Studebaker and Avanti stainless exhaust systems for many years.  I used his system on my '78 to replace the factory cat system with plain old duals. The quality is excellent, and he does offer 2-1/2" if you are so inclined.  Personally, I feel that the 2" is more than adequate for an L48.  While his ads don't list '75-'83 because they have the cat system, he was able to provide the proper exhaust pipes (essentially a '65-'74 system) once we identified which manifolds were on my engine.  I would suggest that you give him a call. 

[pantera928]

1 hour ago, Jim78 said:

Don Simmons at Silvertone Exhaust Systems has been doing Studebaker and Avanti stainless exhaust systems for many years.  I used his system on my '78 to replace the factory cat system with plain old duals. The quality is excellent, and he does offer 2-1/2" if you are so inclined.  Personally, I feel that the 2" is more than adequate for an L48.  While his ads don't list '75-'83 because they have the cat system, he was able to provide the proper exhaust pipes (essentially a '65-'74 system) once we identified which manifolds were on my engine.  I would suggest that you give him a call. 

Thanks Jim! I see that you are in Virginia. Where is he located?

[pantera928]

That looks nice @Avanti83. Good sound?

[Avanti83]

2 hours ago, Jim78 said:

Don Simmons at Silvertone Exhaust Systems has been doing Studebaker and Avanti stainless exhaust systems for many years.  I used his system on my '78 to replace the factory cat system with plain old duals. The quality is excellent, and he does offer 2-1/2" if you are so inclined.  Personally, I feel that the 2" is more than adequate for an L48.  While his ads don't list '75-'83 because they have the cat system, he was able to provide the proper exhaust pipes (essentially a '65-'74 system) once we identified which manifolds were on my engine.  I would suggest that you give him a call. 

Jim is correct except the Silvertone system is 2 1/4" not 2 1/2" as indicated. I have that setup on my 83. He builds them swedged to fit the Vette 2 1/2" manifolds. His standard system is 2" stainless steel.

Here's mine https://forum.studebakerdriversclub.com/forum/your-studebaker-forum/tech-talk/43720-avanti-stainless-silvertone-exhaust-installation-length-and-picture-warning

Don's ad - http://www.studebakervendors.com/silverto.htm

Edited January 26, 2022 by Avanti83

[Avanti83]

40 minutes ago, pantera928 said:

That looks nice @Avanti83. Good sound?

To quote gunslinger - "It's not a real Avanti unless the ground shakes under when you fire it up." This is a real Avanti. My 83 is much quieter.

383 cu in of SBC stroker power.

https://youtu.be/zSHdRthedj0

Edited January 26, 2022 by Avanti83

[pantera928]

19 minutes ago, Avanti83 said:

To quote gunslinger - "It's not a real Avanti unless the ground shakes under when you fire it up." This is a real Avanti. My 83 is much quieter.

383 cu in of SBC stroker power.

https://youtu.be/zSHdRthedj0

Well, if I had a 383 stroker, the sound might match the power. An L48 like I have is just a pretender.

Nice sound!

[Dwight FitzSimons]

On 1/26/2022 at 9:50 AM, pantera928 said:

Thanks Jim! I see that you are in Virginia. Where is he located?

Don Simmons is in Canada.  He has ads in Turning Wheels, and probably also in the Avanti Magazine.  He is a great guy to deal with, and, of course, he ships.

--Dwight

[George Rohrbach]

Avanti83 - 

What are your pipes wrapped with? And how much do you think that it really helps with that nasty Avanti cabin heat problem, that we all deal with? Any problems with rust underneath it?

George Rohrbach

Edited February 7, 2022 by George Rohrbach

[Avanti83]

3 hours ago, George Rohrbach said:

Avanti83 - 

What are your pipes wrapped with? And how much do you think that it really helps with that nasty Avanti cabin heat problem, that we all deal with? Any problems with rust underneath it?

George Rohrbach

The wrap is DEI exhaust wrap, good stuff.. Because the exhaust manifolds are not wrapped there is still a fair amount of heat but it really keeps the heat away from the starter and other heat sensitive items. I've used it on several cars in the past without any rust issues.

It was really effective in my 39 Ford coupe with SBC because there were headers that were wrapped from the heads to well under the car. There's no reason the exhaust manifolds couldn't be wrapped but I've not done that to mine. That should really help with the heat.