Headers Installation...

[mike100]

^^^ don't worry, it will melt the required clearance after a few drives (or you could trim it)- but yeah- headers touch that.

[Shrek]

Ours is that close and our headers have no heat protection at all. After 5K miles it shows NO signs of melting whatsoever!

[Schrade]

Originally Posted by Shrek

Ours is that close and our headers have no heat protection at all. After 5K miles it shows NO signs of melting whatsoever!

Got it; thanks there Jeff. And thanks for the deal on the hardware too...

Road test light hammer, everyone is happy here. Finish fenderwells, and then start on

[Bearly Flying]

Shrade, with the detail you have put into your car, you will have no problem. You are doing a Great job. Your Car will be awesome.

Keep up the good work with the Photo's

[Schrade]

So we're addressing 'drone' / resonance here - sound that's at or below 20 Hz.

3/16" styro-foam board added to the painted top headliner DID reduce interior drone, over a glass top. I noted this after making a recording of interior sound in the car, and then playing it in a media player on the computer, with a graphic equalizer.

Reduction was marginal.

Sheet cork placed under the rear cargo area carpet reduced drone even more, but still not enough.

So now, it's more header wrap on the pipes.

Everything from the X-section back, dropped, and another roll + 2/3 of wrap.



X-section, + 2 aft X-section pieces done. Harmonics I KNOW will be altered with this wrap, as tightly as it's on here...



And rear-most sections wrapped:

[Schrade]

If I reversed the X section, and the aft 2 sections, how would that effect flow dynamics?

[WARP TEN]

Hi Schrade--I see you have a Power Effects exhaust. That was one of several I tried when I was testing exhaust systems in the mid to late 90s. Wrote a couple of articles on exhausts. I loved the sound and the fit and finish of the Power Effects but it has the most horrible resonance of all the systems I tested and there is no real solution to it short of fabricating Helmholtz resonators for it.

As I noted in another exhaust post today in general discussions, when I had my PE system on I had an acoustical engineer from Outboard Marine take the car for a day and test it. He instrumented it, provided graphs of the frequencies throughout the rev range, including the big spikes at 1800 and 3400 rpms, and calculations for the proper sized Helmholtz resonators for each of the two offending frequencies. (Those are what the stock and Corsa systems use to quell resonance). At the time I was in fairly constant communication with the guy who owned Power Effects. I liked the PE system so much otherwise I wanted to help him solve the resonance problem so I sent him all the info I got on how to incorporate the resonators and eliminate the problem. Unfortunately he was primarily a designer and had then just agreed to sell his company so he did not want to make any changes. To this day they sell the same system I tested back in the late 90s. I no longer seem to have the info on the resonance but I believe Jim Voter and Marc Haibeck may still have copies of the graphs and resonator calculations.

As has been noted before, after all my testing of systems I ended up with Corsa for the better part of 15 years on two cars due to lack of resonance and max power, until I finally went back to stock with cutouts.--Bob

[XfireZ51]

PE system always struck me as something a bit overthought and pretty heavy especially in the rear.

[Schrade]

EXCELLENT INFO MR B. PERFECTLY ANSWERS MY QUESTION ABOUT DRONE. KUDOS TO YOU SIR!

Even tho' there's not really a solution, short of buying more hardware - we'll see if any drone reduction can be had with additional wrap, and additional interior sound-damping material, such as Dyno-Mat, or something comparable here.

So think twice Kevin..................

Originally Posted by WARP TEN

Hi Schrade--I see you have a Power Effects exhaust. That was one of several I tried when I was testing exhaust systems in the mid to late 90s. Wrote a couple of articles on exhausts. I loved the sound and the fit and finish of the Power Effects but it has the most horrible resonance of all the systems I tested and there is no real solution to it short of fabricating Helmholtz resonators for it.

As I noted in another exhaust post today in general discussions, when I had my PE system on I had an acoustical engineer from Outboard Marine take the car for a day and test it. He instrumented it, provided graphs of the frequencies throughout the rev range, including the big spikes at 1800 and 3400 rpms, and calculations for the proper sized Helmholtz resonators for each of the two offending frequencies. (Those are what the stock and Corsa systems use to quell resonance). At the time I was in fairly constant communication with the guy who owned Power Effects. I liked the PE system so much otherwise I wanted to help him solve the resonance problem so I sent him all the info I got on how to incorporate the resonators and eliminate the problem. Unfortunately he was primarily a designer and had then just agreed to sell his company so he did not want to make any changes. To this day they sell the same system I tested back in the late 90s. I no longer seem to have the info on the resonance but I believe Jim Voter and Marc Haibeck may still have copies of the graphs and resonator calculations.

As has been noted before, after all my testing of systems I ended up with Corsa for the better part of 15 years on two cars due to lack of resonance and max power, until I finally went back to stock with cutouts.--Bob

[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.