With all thats been going on for the last three weeks I failed to included my new Corvette Central "race only" exhaust system. The system eliminates the pre cats and main cat. I followed BillH advice and sprayed it with bright alum VHT paint. Only took about 1 hour on car ramps. Fitment was great, sound is nice old school rumble buts its my mileage that took off. Last week my wife and I took a nice 600 mile round trip and at one point I was getting a consistant 32 mph. Average before I got stopped for speeding was a very stable 24-25 mph. Eliminated a lot of hesitation and no codes. I thought I would get a strong exhaust smell! none. Cats were probably becoming a little clogged.

That all sounds great. What kind of mufflers are you running?

Oh - What is the MPG at 109?

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Andy I think it was 16mph at 109 but remember I was backing off when caught. The mufflers are still my stock ones that came with it when I bought it new. I thought about MagnaFlow or Borla.

Sounds like your cats were clogging up like you said and you freed up some flow. I run no precats but still have the main cat. Cuts down a little bit on drone and helps the air a bit. Have you noticed any drone with the setup?

Pics of the new system?

Matthew

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Your right about Drone! Its annoying at about 75. Matt when I'm doing this stuff I never remember pics. I know that sounds dumb but once I'm on aroll, in the zone, or deep in zen on the vette I'm having fun and never think of it. Ya know how you were as a little kid at Christmas! did you ever take pics! probably not thats what happens to me, hell I've fallen asleep under the vette. My poor wife thought I was dead once. Thats what zen does. I promise Matt next time I will try to remember. My main shop is at our lake cottage which is about 20 min. away, and I never think off carrying camera.

If you ever figure out how to use your cell phone camera we'll be all set!

Matthew

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Matt I can't find my cell phone You must think I'm nuts! I just don't like phones.

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Throw it away like I did, hell, I don't even wear a watch.

I installed the same system on my '86 about 2 weeks ago. I
put on stock mufflers from a '94 convertible. No drone. Its
pretty loud thru the gears, but at steady cruise its quiet.
I used them because i got them for free. I figured i'd use
them til i could afford "better", but i'm going to keep them.

I hate the drone...

And yes, your cats were about done. Most likely the pre-cats.

Maybe I'm crazy but I love the drone, reminds me of riding in a C-130. my exhaust is pretty wild I think. I have no cat and basically an x crossover about 2 1/2 feet in front of both mufflers.

I did about the same on my 90 the other day. Hedman headers, magnaflow main cat and catback. Talk about SOTP difference. My main cat had already been gutted but I think the Pre-cats were clogged.

I didn't take any pics either