Vegas Panton

I spent this last weekend putting on a free C6 Z06 exhaust system (manifolds, Cats, H pipe) on my 2006 A6. Since I did not have the Z06 mufflers and did not want to use my stock ones, I purchased a set of Corsa Z06 Sports. The only other items I needed were a set of LS7 exhasut manifold gaskets and some O2 sensor wire extensions for the forward sensors. The system fit perfectly except of one place. The A6 transmission is slighly wider where the pan attaches than the 6 speed manual transmissions . The rear section where the clamps are located on the H pipe slightly touches even through I cut the clamps off and rotated them 180 degrees. With some minor exhast work the problem will be corrected. Now the dyno test. The C6 base lined with only a K&N CAI at 343 (1.06 corrected) rwhp on a Dynojet 248. After the Z06 exhaust change the C6 dynoed at 373 (1.05 corrected) rwhp on the same dyno. Both times the car was in the same state of tune with Las Vegas 91 octane gasoline. Overall I am happy with the results. A manual 6 speed car should be a piece of cake. Hope everyone out there has a Happy 2008 New Year

Silverspeed

So you gained 30hp with just the exhaust and NO tuning? Amazing gain still using a manifold. Wonder if any tuning will be needed with this setup? Let us know if you get a check engine light.

Vegas Panton

I used the C6 Z06 exhaust manifolds (no headers) Both sets of hp numbers were with a tune.

Silverspeed

So just a tune, Z06 exhaust, and K&N = 373rwhp? Those are really good numbers for an A6 with just those mods. Congrats.

Vegas Panton

Now that I have had a chance to drive it around a bit, I really like the exhaust sound and the 30 hp has a good SOTP feel . Now I just need a few more HP's to get to 400--Cam or Heads ? So many options and never enough money .

vetracer

I had the same problem putting a 3" system on my A6, I was able to solve it by welding a small spreader plate between the pipes just before the over axle pipes:

Vegas Panton

Great idea and photo of your exhaust pipe modification. I assume that you just spread the pipes until you got the desired clearnace around the A6 and welded in the brace. Thanks .

AintQik

That's a little hard to believe. I'm happy for you!

vetracer

I'll admit I wasn't the one who thought of it. Here's another pic from below the trans showing how tight it is:



We put the car in gear with the brake on to load the engine as well before we put the plate in, you want to make sure that when the torque from the motor loads the drivetrain you still have clearance. Good luck!

Vegas Panton

The owner of the performance shop and I were thinking about 20 hp. When the car dynoed for an additional 30 more hp we were very . I have been on the other end of the spectrum--Hoping for a certain number and getting less . I know that when the Z06 guys put on headers, they don't pick up much. That tells me that the stock Z06 system is pretty good. A cam change really helps the LS7. If you go to www.vegasvettes.com and check under the Dyno tab you can see some of the results of past events. We don't have this years info up yet.

Vegas Panton

Dyno sheets and photos of the differences between the Z06 LS7 exhaust system and the LS2 exhaust system are located at www.ls1tech.com/forums under Generation IV external engine and the thread LS7 exhaust on LS2 = 30 HP

bub

Do you happen to have the source & part #'s for:

1) The LS7 exhaust manifold gaskets (for both heads and both 3" donuts at H-pipe inlet)?
2) Source of your O2 sensor extension wires/weatherpack assy's plus corresponding P/N & $.

TIA



-CKB

Vegas Panton

I used the local Chevy dealer in Vegas that supports $$$ our Corvette Club for the LS7 manifold gaskets (about $30.00). I used the donut O rings that came with the used Z06 stuff. If you don't have that I am sure the dealer would have it. Another good Chevy source would be Gene at www.gmpartshouse.com The O2 wire extensions (about $50.00) I got from Thunder Racing www.thunderracing.com Hope this helps.

bub

Thanks!

bub

Vegas - do you happen to have the exhaust manifold gasket part #'s handy?

Also is it the backs or fronts for the O2 sensors to be extended...I don't have the manifolds in hand yet, but am getting all the parts ready...I also assume you went with the standard loom vs. the fiberglass @ $25 ea?

http://www.thunderracing.com/catalog...&vid=20&pcid=8

TIA.

Vegas Panton

It is the front O2 sensors that need the extensions. Either type from Thunder Racing will work. I think the more expensive ones have a higher heat rating. The extension should not be that close to the exhaust, so I am sure that the basic one should be good. Also make sure that who ever you get your manifolds from that they include the metal gasket that fits in between the uppper manifold and the lower cat portion of the manifold. If it is not included you have have to get them. When you install the manifolds, before you bolt them to the head, make sure you feed the lower cat portion up to the upper manifold protion and bolt them together. If you bolt the upper manifold to the head first, there is not enough room to fit the lower cat portion up to the bottom of the manifolds. If you have someone to help you, there will be no problems with the bolt up . A Corvette tech from our local Chevy dealer told me about this procedure--It worked great. Enjoy the added HP.

bub

Thanks for the tip on installation about top/bottom intermediate joint fit-up.

I'd asked DRM about the intermediate gasket as well (I was curious about that), and am awaiting Randy's reply.

bub

Vegas:

One more dumb question (for now)...

Does the header with the angled heat shield plate go on the passenger side (to protect the starter?), i.e. the header pictured on the right here...

Vegas Panton

You are correct . The extra piece of metal is to protect the starter. When you fit the appropriate lower cat section on to the 4 studs it will align the pipes that feed into the tunnel.

bub

I just got my H-pipe delivered today...man that 3" makes the 2.5" stocker look puny...still awaiting the LS7 manifolds, cats and mufflers...

I had to buy some new clamps for the ends of the H-pipe (as the originals were cut off) but found OEM AccuSeal style clamps online... and for the H's price I paid, I'm happy.

More info than you could ever want to know about the stock style AccuSeal clamps can be found here...real benefit is it doesn't mangle the joint like a typical U-bolt pipe clamp...so that it can be easily disassembled later on...

http://www.torcausa.com/AccuSeal.pdf

Thing is, I had all kinds of problems with this type of joint staying put with the 2.5" Bullets, as the Bullet OD was slightly under OEM 2.5"...I had to add a shim between the ID of the AccuSeal and the OD of the H-pipe to get the clamping force up before the clamp "bottomed out"...

With stock components (H & catback) it's a non-issue (the ID's/OD's are to tolerance suitable for the clamp "travel".

Just a FWIW to others...



Vegas...I'll probably have more Q's as I get further into this...

Also of note, the Z's H is radically different than the stock H - different shape, differnet inlet flange location, inlet c/c, outlet pipe angles & c/c, even the spring hanger bracket is different...

I had originally planned to morph a Z H to a stock H and keep my stock manifolds/cats, but after seeing the 2 H-pipes side by side, that may be more trouble than installing manifolds...