I have a 95 Z28 M6, stock engine internally , only mods are mac mid headers, CAI, and Magnaflow cat back/not counting suspension. about 104 k on original engine, I've owned for 3 years, put 10k miles on it. never had any issues. Took it out this week when we had a sunny day/Monday and noticed that there was slight loss of power when shifting from 2nd to 3rd and 3rd to 4th. never got it higher than 4th. I shift around 2200-2400. In addition to my feeling of loss of power, the exhaust was louder when increasing speed, not noticed in 1st gear. my exhaust is quiet until wot, but seemed louder, reminded me of carbed sbcs. There are no ses or check engine lights. I have not scanned for codes, will do this weekend when i get some time as I have an older Actron scanner. In doesn't have the tick tick sound of an exhaust leak? In a previous 4th gen, i had a similar experience and it turned out to be a bad cat. I believe the cat is original, but have not checked. Any thoughts? thanks for your time & expertise. respectfully submitted

 

Dude, Google says there's thousands of ways to test your cat. But you will have to get off the computer and up from your chair to try one.

 

Boy oh boy. People just aren’t out to help anyone anymore, are they?..

In short, it could very well be the cat. My recommendation if they don’t hook sniffers up to your exhaust for inspection in your state: gut it and call it done.

With loss of power, it could be starving for air or fuel as well. Have you checked the fuel pressure lately? May try that. Also check your air filter for any blockage or heavy debris. Good luck!

 

thanks everyone, I will get on it this weekend, just wanted to hear from the folks who know the LT1 cars way better than me. I will use google and all the forums with the likes Injuneer, Gorn, Crabbe etc.....thanks Cardo & Chaotic for chiming in....

 

Anytime, brother!

 

Testing a cat requires a direct pressure test. A plugged cat will not through a code. Normally exhausts gets a muffled sound not louder.

There are a lot of things that can cause a drop in power, even a fuel filter.

 

It is a federal law to remove the cat.

With that said, if you don't have a sniffer test, the best option is a hollow cat. This is where I got mine. DSM Intercooler Piping

 

Thanks for the info, we don't have sniffer test, they just plug into the car and scan

 

Thanks for the response

 

yep fuel pressure would be first thought, check e brake/brakes make sure they is not sticking. check fluids in trans and rearend.