Early Callaway Twin Turbo - Exhaust Question to replace megaphones

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J_400
Posts: 1
Joined: Thu Dec 30, 2021 10:44 pm
Location: Detroit, Boise, Las Vegas

Early Callaway Twin Turbo - Exhaust Question to replace megaphones

Post by J_400 »

This is great information, thank you. Can you post pics of your exhaust? I plan to replace mine as I never really cared for the megaphone tips. Did you lose all your cats or go with high flow?

Thanks,
John
*89x2*
Posts: 478
Joined: Tue Oct 21, 2008 9:58 pm

Re: Early Callaway Twin Turbo - Exhaust Question to replace megaphones

Post by *89x2* »

John,

I split your post from the other thread to hopefully gain some more attention to the subject.

Welcome to the Callaway Owners Group and congrats on the new car! :hi
callaway4fun
Posts: 352
Joined: Wed Aug 27, 2008 8:12 pm

Re: Early Callaway Twin Turbo - Exhaust Question to replace megaphones

Post by callaway4fun »

I had the stock exhaust on my Callaway and the car was very quiet. It did not have a performance sound like the megaphones . My car was in a magazine on Oct 2008 Corvette Enthusiast with other Callaway owners and Zr1 owners . All that drove the car loved the sound of the Megaphone exhaust and the sound of the turbos spooling could be heard six cars away while driving down the road.
*89x2*
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Re: Early Callaway Twin Turbo - Exhaust Question to replace megaphones

Post by *89x2* »

Give the megaphones a chance. The first Callaway I heard on the road was an 87 with megaphones. It sounded like nothing else. Really good in my opinion.

Regarding the post above from Callaway4Fun, I've driven his car with megaphones, and it's a sweet sounding car. He's got a small cat on each side of the large exhaust, then back to the megs. Sounded amazing. Let us know what you think once you get the car, and congratulations.
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undercover
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Re: Early Callaway Twin Turbo - Exhaust Question to replace megaphones

Post by undercover »

J_400 wrote: Sun Jan 02, 2022 7:20 am This is great information, thank you. Can you post pics of your exhaust? I plan to replace mine as I never really cared for the megaphone tips. Did you lose all your cats or go with high flow?

Thanks,
John
What's your goal here? I assume you have an '87 because I think the later cars had mufflers. Are you looking to change the appearance, improve the sound, or increase performance, all of the above?

Count me as not a fan of the megaphones. The whole '87 exhaust system is pretty bad - very restrictive, same as stock L-98 minus the mufflers. Callaway had to stick with it for certification purposes, and they eliminated the mufflers to increase the sound since the turbos do quite a bit of muffling on their own (i.e. the Callaway would be quieter than the std Corvette if the mufflers were left in place.) Mine just sounded like a truck with no mufflers. Sounded OK when you're getting on it, but for just cruising around, it sounded 'cheap' to me.

On mine, for now, I've ditched the main cat, replaced it with a resonator (3" bullet muffler) and put dynomax super turbo mufflers on. It sounds GREAT - deep rumble, no drone, good volume when you get on it. However, it's still a very restrictive system and I feel is holding the engine back quite a bit.

I've got a 2.75" Borla system I want to put on, but I have to fab up some pipes that eliminate the pre-cats and connect to the turbos. I have a spare front-Y that's been hacked up a bit that I'm going scab the first foot or so off of to make connecting to the turbos easier. I think this setup will sound great and will wake up the engine even more.

Tom
1987 CTTC conv #147
1987 Guldstrand/Traco Grand Sport 80 #18
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