455HOGT37

Has anyone installed a complete Z exhaust on a stock LS3 and run it (before and after) on the rollers yet? Looking for some concrete performance changes between the two. Anyone?

Gold Z

Since I did this mod I also would like to know the gains.

StoplightWarrior

I'm considering this, too...up!

Keith N

Here is a link to JBSBlownC5(Joel)'s LS3 with the Z06 mufflers added (many bolt on mods) - http://forums.corvetteforum.com/c6-t...ull-video.html.

Here is another link for a LS2 & full Z06 exhaust system - http://forums.corvetteforum.com/c6-t...s-project.html.

I have a C6 LS2 supercharged. I gained +41 rwhp and +24 rwtq with the full Z06 manifolds, cats, H-pipe & Corsa Sports + retune. Recently, I've added the Z06 mufflers with the NPP In a Box.

AgDriller

Hey Keith N, were you able to use the same 02 sensor wires or did you use the Z06 length wires? I'm putting mine on this weekend. Looking forward to seeing the difference. FWIW, mines an LS2.

Gotcha

I've got some dyno results with LS7 manifolds and a small cam in my 08 LS3.

http://forums.corvetteforum.com/c6-t...post1566887804

455HOGT37

There's enough extra length hiding under the tape wrap to make the distance... At least there was on my '08.

AgDriller

I've read that before, so I hope I can do that, too.

Keith N

The same 02 sensors were used. I had the full Z06 exhaust installed by a shop. Good luck, I'm sure you'll be happy with the results.

adam205348

I know not everyone has the NPP from the factory on their LS3 but if you do I would suggest putting the money for the Z06 mufflers somewhere else and keep your NPP as it is because you really will not pick up much if any.

455HOGT37

Well, I was non-NPP to start with, so that was a gain for me, but the LS7 manifolds are much better than the cast iron LS3 units. On top of that, the cats should flow better, and the system is 3 inch vs. 2.5... All that should add up to some horsepower gains over even the NPP LS3. Apparently no one has run the car on the track or rollers before and after to get some real numbers from a completely stock car. Maybe we can all pitch in a few bucks for dyno time to the next guy who is going to do this mod?

ROD BROWN

When installing the Z06 complete exhaust system on the LS2,did you have to retune the car? Just curious.I am sure it will pass the smog check here in L.A.,which will mean you won't have to reinstall the stock exhaust every 2years.What a pain.That may be the solution to the R& R every 2 years.:fla g:

oldmansan

I've seen some here post numbers that were substantial, but not sure if I saw any before and after numbers with nothing else changed. I would go LS7 manifolds and exhaust over NPP any day of the week.

San

oldmansan

I'd like to think since the Z06 motor has more cubes that the complete exhaust would "cover" an LS2/3. I'm in Cali too, and just had to install a complete stock catback on my other car to pass emissions. I'm not trying to go through that again.

San

Keith N

The Z06 exhaust system flows much better than the 2.5" LS2 system. With the SC kit on my C6, I had Charlie at RPM Motors do the retune on his dyno.

adam205348

Well the problem is that yes the manifolds are better and the cats and the H-Pipe because they are 3in pipe. BUT the mufflers neck down to 2 1/2in when it enters the mufflers and the Exhaust system only flows as good as the smallest section.

So yes you might pick up some over Non-NPP exhaust or over the LS2 exhaust but not much because of where the pipe necks down to 2 1/2.

dkrhardy

The sound difference alone is worth it when compared to stock exhaust. IF you get a good price from a member or the auction sites. There are good ones out there and IF packed properly they will arrive without damage.

LJD51

I installed a complete Z06 exhaust from manifolds to tips recently and it was one of the best things I have done.

I was able to pick up the manifolds, gaskets, cats and h-pipe for $175 and the mufflers for $460; I also bought all of the seals, bolts and nuts for the entire system from my local Chevy dealer ($120) just in case something broke or was missing.

I had the system installed and during the installation it was determined that the stock O2 sensor wires were not long enough (I had not bought extension wires or Z06 sensors...) but the tech make custom extensions and wrapped them in sheathing to look like OEM. The installation and custom work cost $900 and all totalled, the entire system cost $1,655; I also added the Mild2Wild for $150 bringing the final total to $1,805.

I am completely happy with the setup; the Z06 manifolds are like shorty headers and the sound is deep and throaty. With the exception of the 02 sensors, they are a perfect fit to the LS2. I had it re-tuned to adjust the A/F ration due to the increased airflow.

455HOGT37

Yes the Z system necks down at the mufflers, but that does not hurt as much as people might think (if at all) because the exhaust has cooled a lot by the time it gets all the way back there. Exhaust systems on cars do not work soley on hydraulic principle; exhaust gas tempertature plays a big part in the flow requirements (i.e. pipe size) and it really doesn't need to be the same size all the way to the rear. My 455 powered 63 Catalina drag car will have 3 inch mid pipes transitioning to 2.5 over the axle just for this reason. The "ultimate" exhaust would start out at the optimum size at the engine and taper down all the way to the back. Good luck finding that tubing at the muffler shop! However, I know for a fact that some Superbike (4 stroke) racing teams used tapered tubing to make the headers because to the temperature difference between inlet and outlet. The cheaper version of this concept is "stepped" headers; sometimes used in drag racing and circle track.

455HOGT37

I've been in California my whole life, and I can't believe ANY smog tech will fail you on a visual inspection for the Z system. As for (test) performance, as long as the o2 sensors function and the cats light off, it will pass. Just don't mention the exhaust has been changed and you will be fine. IMO.