Headers Installation...

[efnfast]

Originally Posted by KILLSHOTS

Since this is turning into more of an exhaust thread than a header thread, vis-a-vis the drone issue, I just gotta say: Corsa is unreal! Confirmed on my first highway drive today. ZERO drone at any RPM with a system that's basically straight pipes. Amazing, amazing system.

My OBX, that is a copy of Corsa, also has no drone.

[Paul Workman]

Originally Posted by efnfast

My OBX, that is a copy of Corsa, also has no drone.

Not zackly a copy...

The "resonator" of the OBX uses perforated tubes - like a "glass pak" muffler might have, whereas the Corsa is a true (Helmholtz type) resonator. The difference being the Corsa utilizes an opening at the front of the chamber for sound waves to enter, then be reflected out of phase (thus cancelling) the low frequency sound waves. And too, IIRC, the Corsa mufflers too have a similar setup, but are affective in cancelling the higher frequency resonance (occurring around 3.4K rpm).

As far as performance goes, outside of noise reduction, Marc Haibeck and Pete do not appear to be of the same opinion on the matter. As I understand it, on the one hand, Marc H. is on record favoring the Corsa as part of his 510 hp upgrades, whereas Pete is of the opinion that what is essentially a modified 3" B&B type with a "Stainless Works" type X-pipe and flappers (for resonance abatement) is better. Both are successful at making power from the 5.7L LT5s (among others).

I followed the 3", X-pipe route, because it was cheaper and easy for a DIY'er to fab up, AND it seems to be a proven system (Pete's car, among others), And because too it preceded Marc's announcement regarding the findings he made with the Corsa. Also, the Corsa cancels the low frequency resonance, but does not address the high frequency notes, resulting in a "tinny" sound - at least to my ear: a personal thing.

I'm at 432 rwhp w/ stock TB and cams using what is essentially Pete/B&B approach (see signature). And, it drones. I can't wait to install the NPPs to address that issue!

Getting to this point has been a trial and error journey. And, in the end I can't say I saved a nickel or have realized performance over what might have been the cost of the Corsa. Performance trumps sound, IMO, and Pete's system seems to have both of what I like...EXCEPT that drone - the reason I'm interested in installing the NPPs (with Mike 100's control system) as soon as possible.

[XfireZ51]

Paul,

I'll have to give you a ride in mine and see what you think.

[Paul Workman]

Originally Posted by XfireZ51

Paul,

I'll have to give you a ride in mine and see what you think.

Love to!

I studied Mike's system, and was especially interested in his experience with mountains - leading to his active (electronic) control system vs. vacuum only. Soon I believe I will duplicate his system, or perhaps resort to a simple manual switch approach - haven't decided yet.

Note: Mike's article appears in the (members only) ZR1NetRegistry's New Letter.

[XfireZ51]

For those interested in the Z06 setup, here's a vid of Al's car w the Z tips, DynoMax UltraFlows and SW Xpipe.

https://www.youtube.com/watch?v=GahF...ature=youtu.be

[Billy Mild]

So overall how hard of install of the headers is this? It sounds like some of the issues were from the size of the automatic transmission you have. Is that correct?

How long would an install take? Any special tools required?

[Schrade]

It wasn't difficult at all. Just about all steps are in this thread (along with lots of other junk of mine).

Only tools I bought was a set of swivel head gear wrenches that Cliff suggested. I have a new set of offset gear wrenches that you can have for postage - got a snappic here somewhere, although I don't know that you can get away with it on header removal.

The automatic was a minor issue, even tho' the exhaust hardware (minus headers) is made for LT1 C4 W/ 4L60e, I do believe. And my auto was built INSIDE a '95 C4 4L60e case. You won't see that issue of course...

I spent about 2 weeks on it, but only because I get carried away cleaning everything that I can get a solvent sprayer and paintbrush on, when parts are out of the way.

[Billy Mild]

Originally Posted by Schrade

It wasn't difficult at all. Just about all steps are in this thread (along with lots of other junk of mine...

Only tools I bought was a set of swivel head gear wrenches that Cliff suggested. I have a new set of offset gear wrenches that you can have for postage - got a snappic here somewhere, although I don't know that you can get away with it on header removal.

The automatic was a minor issue; you won't see that of course...

I spent about 2 weeks on it, but only because I get carried away cleaning everything that I can get a solvent sprayer and paintbrush on, when parts are out of the way.

http://shop.advanceautoparts.com/p/g...543/25984326-P

I have a set of these in metric. Did you need something other than these?

[Schrade]

Originally Posted by Billy Mild

http://shop.advanceautoparts.com/p/g...543/25984326-P

I have a set of these in metric. Did you need something other than these?

I'm pretty sure that's all you need.

Plus an extension for the passenger side O2 connector. I got lucky fabbing one up with splicing clips, but everyone suggested against it. Using dielectric grease, and RTV to seal might have made the difference in my case.

Access to the P side O2 harness connector might be a challenge. It's behind the P side motor mount. I couldn't even see it to shoot snappics...

[Schrade]

Drone / resonance in the interior - is just about gone, although I STILL would like it quieter if possible.

The pipe wrap took more off, than the extra styrofoam in the headliner, and the cork sheeting underneath the rear cargo carpet COMBINED.