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Discussion Starter #1 (Edited)
This exhaust system is as bad if not worse than the stock LS1 F-Body's drivers side crimp job. Check it out...









I'm fixin' to fix that :D





Stay tuned for more pics :)
 

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It will be nice if the headers go up from the bottom! I've done two sets on F bodys, and they had to go in from the top. Never figured that valve covers would have to come off to install headers. The Goat should be cake.
 

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Discussion Starter #7
rock421 said:
It will be nice if the headers go up from the bottom! I've done two sets on F bodys, and they had to go in from the top. Never figured that valve covers would have to come off to install headers. The Goat should be cake.
Drivers side feeds in from the bottom. Ya gotta snake it in with the rack dropped and feed the P/S lines through as shown. Kind of a pain... but necessary with the rack behind the motor instead of in front. The passanger side is cake... drops right in from the top. :)
 

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Cool, thanks. I think that headers and a 100 shot should get the job done when the 05" arrives.
What are we doin about "big brother" and his OBDII chronies????
A chop right behind the aft cats with a new back half system would eliminate all of the factory crimps. The stock manifolds don't look all that bad if that was the only legal option.
I wonder if any of those crimps were put there intentionally to achieve the "GTO sound" they were looking for?
 

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Discussion Starter #9
This ride is getting the Stainless Works full exhaust system. Headers... and full 3" stainless with X, high flow cats, and chambered "mufflers" ... with a single oval style exit in the stock location. We have found with this kit that the front and rear O2 sensors are not long enough for their new locations. I have new style 04 Corvette front O2 sensors on order for the fronts... same sensor and connector just much longer pig tail. I have extensions for the rear O2 sensors... which have the same flat4 style connector as the OLD C5 Corvette front O2 sensors.

This car will still have fully functional front and rear O2 sensors. It remains to be seen if the PCM pops a code or 2 due to the high flow cats. We'll see.

The stock cast iron manifolds have small ball joint style exits. The exits are smaller than a stock C5 cast iron manifold. Yet this engine in either car produces the same rear wheel results. Pretty amazing considering the amount of crimps in the stock GTO exhaust system. BTW, the crimps are there because of the exhaust systems proximity to other parts underneath the car.
 

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Bill Reid said:
This ride is getting the Stainless Works full exhaust system. Headers... and full 3" stainless with X, high flow cats, and chambered "mufflers" ... with a single oval style exit in the stock location. We have found with this kit that the front and rear O2 sensors are not long enough for their new locations. I have new style 04 Corvette front O2 sensors on order for the fronts... same sensor and connector just much longer pig tail. I have extensions for the rear O2 sensors... which have the same flat4 style connector as the OLD C5 Corvette front O2 sensors.

This car will still have fully functional front and rear O2 sensors. It remains to be seen if the PCM pops a code or 2 due to the high flow cats. We'll see.

The stock cast iron manifolds have small ball joint style exits. The exits are smaller than a stock C5 cast iron manifold. Yet this engine in either car produces the same rear wheel results. Pretty amazing considering the amount of crimps in the stock GTO exhaust system. BTW, the crimps are there because of the exhaust systems proximity to other parts underneath the car.

By looking at those pics that almost makes me sick. The exhuast flow of that they are impeding is HORRIBLE. I don't undertand the needs to bend and crimp in that manner. By seeing these pics I now know that a fully stainless mandrel bent exhaust will do wonders for this car. I am pretty sure with straight through cat's you would throw a code on your PCM but with High Flow cats I think you might be able to get away with no codes. In my experiences the high flows seem to work wonders on not throwing codes. I hope to see some pics of the full system when on, and maybe even some dyno numbers so we all can see what kind of gains a full header and exahaust system will provide.
 

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Discussion Starter #11
I will post final pics of the exhaust install. I will also post dyno graphs/results... (before and after exhaust install). The Harrop rear diff cover was installed when the exhaust was out. We just got our Magnuson kit on Friday... so, after the post exhaust dyno that kit will go on. The car will then be tuned and more dyno graphs/results will be posted on a new "Magnuson Install" thread :)
 

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why is there no drool smilie :D
Sounds like your car will be a beast!

Be sure to get track numbers, and if possible monitor your temperatures with the supercharger... i wanna see how it will affect the GTO oil, coolant, and any other temperature.

I wonder if the oil will heat up faster becasue of the increased strain casued by the supercharger :confused
 

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Discussion Starter #13
Well, we finished up the exhaust install this morning and put the car on the dyno. We picked up 14.6rwhp and 14.6rwtq. Below is the graph...



Here is a few final shots of the exhaust and Harrop cover :)









 

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Discussion Starter #16
Sent you a PM :)

We did not experience any codes after installing the exhaust system... which includes the high flow cats. I think its hit or miss as to whether one may experience cat efficiancy codes after installing high flow cats. We have found that generally high flow cats will throw codes... at least they do on C5's. We haven't experienced any codes on the GTO... and we have put several hundred miles on the car after the exhaust install.

Magnuson install in complete... we'll start another thread on that next week :) If interested in details any quicker than my post just shoot me a PM and I'll give you my phone number to call :)
 
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