LS1LT1

Am I reading that correctly, you gained 25rwhp and 19rwtq from tuning alone?
How far off was your factory A/F and timing I wonder.

Boomer111

I agree seems like a lot just from tune. Remember this was on a Dynopack. Some have thought that the stock numbers were lowered on purpose. I dunno really. The Tuner is well respected and has been featured in magazines. I saw, felt no reason for him to deceive me.

The car since has been around 12.5 a/f for the other tunes. I was told by second shop that the initial tune ( Dynapack ) was a little unsafe, just a bit he said. Take all this with a grain of salt..right! Everybody wants to be the Man and sometimes cut the other guys work, pretty common I feel. But if true might help explain the initial tune numbers.

The second shop also is a well respected Tuner with lots of experience in the Drag scene. Guys come from all around for his services.

This whole topic is just for some comparisons nothing is in concrete, not 100% scientific method, too many variables.

Just some information with my mods as they came along over a couple of years.

My Dynapack graph does not include a/f readings.

ˆwould not expect anyone to take these numbers as gospel. I think that trends can be formulated though.

First these factory LS3 do respond to a tune.

Second Long Tubes do give some nice gains.

Intakes are probably a waste of $$. The LS3 seems to breath very well.

Third the Z06 conversion does work and for the money and shows appropriate gains while being Emissions friendly at a fraction of the header cost too.

Just numbers no "real world test" you track enthusiasts like like to see.

What else can I say? Not representing this in any other light.

HOXXOH

First, I'd like to thank you for sharing the testing information you've done. It's why this forum works so well.

My own "real world test" of the Z06 vs. headers will be coming soon when I pull off the Z06 system after a Saturday track session and install headers in time for a track session the next day. I presently have the cats gutted and will run catless on the headers too.

I believe the pipe sizing to be more important to the flow velocity at any given point in the system. With the stock cam, the LS3 appears to respond well at the track if the pipe size drops from 3" to 2.5" at the back of the H-pipe. I'd suspect a bigger cam would like a little more of the 3" length to compensate for the higher RPM capability.

A CAI shows next to nothing on a dyno, but means a lot at speed. Just getting beyond the underhood hot air is significant. I'ts not the ablility to breathe better, but just introducing denser air.

OBSSSD

Great post! Thank you for all the hard work to get these numbers. As already stated 1-7/8" headers would probably pick up that much more than the current difference and that is with the stock cam. It shows the LS7 manifolds are a great bang for the buck mod for those on a budget or with emissions concerns.

Jim_H

Powerlabs did a test on his 600hp car going between 1-3/4 and 1-7/8 and barely gained 5 hp. So header size isn't really going to make much difference especially with a stock cam and heads. Here's that post.

http://forums.corvetteforum.com/c6-t...p-results.html

I think the OP's test shows that the Z06 manifolds pick up 70% of what headers do under the OP's test conditions. All for a fraction of the price and without any downsides. It wasn't a price issue for me just a preference.

I haven't seen limitations in my gains using them when I did a heads and cam, and later when adding the Fast 102. My gains were all in line with what cars with headers were gaining.

I think the experiment HOXXOH will do is going to be a good test.

SpinMonster

Thanks for sharing the detailed and very usefull info. Selfless acts to help out the forum are what makes this such a great place to get info.

I have to say, I find it interesting to see the bigger than expected dyno loss of gears. When I did Craigster05's H/C package and it made462/420 we see its really more like 477/437 using unported LS3 heads. My car did 471/435 through 4.10's with a 228/232 cam. That looks to be more like 486/452 by these findings. A debate took place because a tuner's ported LS3 head package did 482 on stock gears at a 1500 dollar premium so he was defending the gains with ported heads. I was saying porting LS3 heads didnt gain anything and the difference was due to gears on my car. He said gears dont lower the dyno reading.

Thanks again, and keep this in mind next time you see XYZ cam make a few ponies less than expected on a geared car.

SpinMonster

I was one of the doubters of the Z06 system but the West Coast guys do have a legit benefit from the use of the Z06 exhaust. I was wrong on that one.

TPSMak

Yeah in CA we have some pretty stringent smog laws so we don't sell and install alot of Long Tube headers because of problems with getting them to pass the visual for smog.... so Dave contacted me about removing his ARH Catted Long Tube Headers & Vararam to make it easier to pass smog.. so after some thinking decided to do some testing and to try and find a solution for some of our customers. We believe we've found a nice solution for our customers who want headers but don't want to hassle with the issues of getting their car smogged easily in CA.

BTW, here's the video of his car on our dyno

http://www.youtube.com/watch?v=3GA7_...el_video_title

2010 Silver GS

Thanks for the effort with this "Study." I did the Z06 Manifolds, Cats, and H-Pipe. Had my dealership install them! Also installed the VaraRam at the same time. No Dyno, but I will say I certainly can tell the difference. Car fights even harder for traction from the line and down-shifiting from speed is just downright awesome...it just flat out pulls harder than before. No track results, but a few weeks ago a GTR tried to pull from me at about a 40 MPH roll. FAIL...silly rabbit...rice rockets are for kids. Figure I talk trash now before the 2012's hit the street. 0-60 in 2.9...WTF

Picked mine up from EBAY for like $200. Buffed them out with 'Mothers' and they looked brand freakin new after a few coats.

Boomer111

I appreciate all the positive comments. My hope is that this information will help others that find themselves in a similar situation as myself.

Mike at TPS has been very supportive with this project. Being based in California he understands that the Z06 exhaust option for the LS3 might be a positive platform to expand to. He wanted to see for himself if the change over would be beneficial from a power/cost perspective.

Obviously I liked the long tubes but just was not comfortable with the Emissions concerns.

The car still has a more aggressive sound than stock. The Corsa Sports help here as does the 3 in. tubing. Just enough for my stately 63 years.

Again all the positive reply's have been heart warming.

Boomer111

I understand this and concur. The Vararam is not California legal and after all I do not track or even street race. From my point of view now it was a waste of $$.

The wise advice given when modding is, define and understand your final goals. I obliviously did not do this and while I had fun I ended up back stepping. which proved to be costly. Not the end of the world by any means but just a little embarrassing in my own view.

PRE-Z06

Remember his car also didn't loose any lowend and it's an LS2 with a smaller bore and not as good of heads.

OBSSSD

There have been a couple good posts where the gains from switching from 1-3/4" to 1-7/8" headers on bigger than LS2 engines made an at least an additional 10/10 through the powerband like here:

http://forums.corvetteforum.com/c6-t...exhaust-2.html

The car above picked up 26rwhp with no other changes than going to the bigger primaries. The LS7 exhaust is a great bang for the buck exhaust that is emissions legal, but it does not produce 75-80% of the gains of the bigger headers in LS3 applications. Maybe you get 60% of the gains in an LS3 car which is still good but then again the cost is way less. I thank the OP for the comparitive post it is great information, but I felt the extra power and weight savings more than justified the header purchase for me.

Boomer111

Emissions was my primary concern. It was a compromise for sure.

Neumonic2002

Great post!

When I took my stock exhaust system off my LS2 and switched out with AR Header setup with their high flow cats I only saved just under 20lbs....just another piece of the manifolds vs headers

Bill Curlee

Great post!! May consider this for my 11 Grand Sport if i dont get headers...

How does the ZO6 system bolt up to the stock Grand Sport NPP Exhaust?

BC

Jim_H

Buy a full Z06 system including mufflers for probably $750 or less, sell your stock NPP for $800 and pocket the difference.

Or you can do a reducer at the H-pipe and use your NPP, this is the best way if you have an A6.

AR Headers

I would postulate that if you put in a cam, the gap between the Z06 setup and long tube headers would grow quite a bit.

So Boomer....please post up another analysis when you put in a cam![/QUOTE]

Joe you are correct. Introducing a cam into this would prove a drastically different result. As an example, we often see a 35-40 RWHP gains on cammed ZO6's going from manifolds to headers.

I would also like to see the graphs as I don't believe the peak numbers tell the whole story. I understand the issues with CA and why someone would entertain the idea but someone looking for peak performance won't get it with manifolds of any type when compared to a quality set of headers. Enjoy your ride.

Nick

Boomer111

Joe you are correct. Introducing a cam into this would prove a drastically different result. As an example, we often see a 35-40 RWHP gains on cammed ZO6's going from manifolds to headers.

I would also like to see the graphs as I don't believe the peak numbers tell the whole story. I understand the issues with CA and why someone would entertain the idea but someone looking for peak performance won't get it with manifolds of any type when compared to a quality set of headers. Enjoy your ride.

Nick[/QUOTE]



Not insinuating otherwise. The graphs are very similar really outside of the peak numbers.

No cam in the future.

I understand that most want the most power with the mod picked.

This is a compromise for sure, but my primary goal of passing Emissions has been meet while still keeping some power on the table.

So from a stock 375 rwhp I have approx. 415 with tune and Z06 set up.

Again the gear change clouds things a bit. Anyway this is how I have it figured.

TPSMak

100% agreed.. LONG TUBE HEADERS would produce better numbers.. no doubt about it... the before dyno numbers on this car showed that there was a 7RWHP difference. BUT, that was also based on the tune from the other shop, we may have been able to squeeze out more from the car if we retuned it

Unfortunately, we have smog issues to deal with in CA