boonie c4

On my 08 LS3 Ive Installed the NPP mufflers made for the LS3 exhaust upgrade now I have a opportunity to purchase a complete Z06 exhaust system this purchase includes both exhaust manifolds, catalytic converters, H pipe. my mechanic wants $700.00 to install it but before investing cash into this project I wanted to run this upgrade by you forum members to get your opinions. 1 I'm expecting to see at least 30hp increase. 2 expecting to see the car and engine compartment to operate at a lower temperature. so should I spend or save my money?

HOXXOH

The realistic HP is in the 12-15 range and you won't notice it with your butt dyno. I'm not saying it isn't a worthwhile mod, but just that by itself and nothing else, it's not cost effective, nor will your engine bay run cooler. If you plan future mods, such as a CAI and a tune, then the exhaust system becomes an integral part.

If the $700 is only for installation, you need to find another mechanic. I recently helped a friend do that same job and it took less than 3 hours on jackstands, using hand tools, in no rush, and we're both in our 70's.

johnodrake

I like the sound better too. I did the Z06 exhaust on my 06 when I put the built LS3 in it. I later replaced the Z06 mufflers with ZR1 and that sounded even better. At the end of the day if you like it go for it. If you are are a racer looking for 0.1s anything helps.

Mike's LS3

Without a tune expect around 12-15 hp, with a tune 25+ depending on your mods.

As far as cooling the engine, the freer flowing Z06 exhaust will help reduce combustion chamber heat. This will help prevent detonation and you may be able to add a little more timing. I did notice a few degrees cooler at cruise.

Andy05C6

I just did ls9 manifolds, cats, and x pipe about a month ago before doing my cam swap. I drove it for a week with just the exhaust. I got all my parts from a 2011 zr1, but had right at $100 in everything. I couldn't tell a bit of difference in power once I got them on, but did notice the sound. To me it seemed a bit mellow. I did keep my mufflers, they are not the best, look like flow masters, but we're on the car when I got it.

Now after the cam install and tune I noticed a huge difference.

My vote would be that doing the exhaust alone wouldn't be worth it unless they were free or cheap.

Andy05C6

I should also mention that the installation was super easy. Just a few hours.

redbird555

For the gains you want I’d be looking at a set of long tubes. Not sure what they want for the z06 system parts but for 800 or so you can buy Hinson lts and an orx