Headers do help.
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Headers do help.
This information pertains to the 997TT and comes from a posting by IA.
In previous threads IA posted charts that when overlayed showing gains of 16 Hp and 15 lb-ft. when the headers were bolted on to an engine with a tuned ECU and compared to stock headers.
When we overlay the posted charts the gains appear to start at 4200 rpm and carry on to red line.
From 2800 to 4200 the headers performed better than pure stock engine but not as well as tuned ECU with stock headers.
From 2000 to 2800 quite a bit less power than pure stock or tuned ECU and stock headers.
My conclusion, good gain from 2800 rpm for some loss below 2800, worth it in my estimation.
As the headers were just bolted on and run it is not obvious whether the loss bellow 2800 can be tuned in with the ECU.
I printed both graphs on the same scale and made an overlay to come to the above results, someone at IA may have more accurate information.<!-- / message --><!-- sig -->
In previous threads IA posted charts that when overlayed showing gains of 16 Hp and 15 lb-ft. when the headers were bolted on to an engine with a tuned ECU and compared to stock headers.
When we overlay the posted charts the gains appear to start at 4200 rpm and carry on to red line.
From 2800 to 4200 the headers performed better than pure stock engine but not as well as tuned ECU with stock headers.
From 2000 to 2800 quite a bit less power than pure stock or tuned ECU and stock headers.
My conclusion, good gain from 2800 rpm for some loss below 2800, worth it in my estimation.
As the headers were just bolted on and run it is not obvious whether the loss bellow 2800 can be tuned in with the ECU.
I printed both graphs on the same scale and made an overlay to come to the above results, someone at IA may have more accurate information.<!-- / message --><!-- sig -->
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Joined: Apr 2006
Posts: 5,260
From: Austin
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This information pertains to the 997TT and comes from a posting by IA.
In previous threads IA posted charts that when overlayed showing gains of 16 Hp and 15 lb-ft. when the headers were bolted on to an engine with a tuned ECU and compared to stock headers.
When we overlay the posted charts the gains appear to start at 4200 rpm and carry on to red line.
From 2800 to 4200 the headers performed better than pure stock engine but not as well as tuned ECU with stock headers.
From 2000 to 2800 quite a bit less power than pure stock or tuned ECU and stock headers.
My conclusion, good gain from 2800 rpm for some loss below 2800, worth it in my estimation.
As the headers were just bolted on and run it is not obvious whether the loss bellow 2800 can be tuned in with the ECU.
I printed both graphs on the same scale and made an overlay to come to the above results, someone at IA may have more accurate information.<!-- / message --><!-- sig -->
In previous threads IA posted charts that when overlayed showing gains of 16 Hp and 15 lb-ft. when the headers were bolted on to an engine with a tuned ECU and compared to stock headers.
When we overlay the posted charts the gains appear to start at 4200 rpm and carry on to red line.
From 2800 to 4200 the headers performed better than pure stock engine but not as well as tuned ECU with stock headers.
From 2000 to 2800 quite a bit less power than pure stock or tuned ECU and stock headers.
My conclusion, good gain from 2800 rpm for some loss below 2800, worth it in my estimation.
As the headers were just bolted on and run it is not obvious whether the loss bellow 2800 can be tuned in with the ECU.
I printed both graphs on the same scale and made an overlay to come to the above results, someone at IA may have more accurate information.<!-- / message --><!-- sig -->
"We have build and tested headers for the 997 Turbo but we couldn't measure consistent performance gains on the dyno.
Couldn't feel any gains while driving the car either. ( that was with the sport muffler already fitted )
I'm sure it will be great for big hp engines , we won't offer them though."
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The key to spool up is exhaust gas velocity. If the headers have larger primary tubing diameter, exhaust velocity will actually be slower, which results in more lag. Bigger headers are more suited to larger turbos. The stock VTG's do flow more than a K24, but only when chipped to do so. For a stock car, I would guess the larger headers might even hurt street performance.
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Agreed.
I imagine anyone going to the expense of headers would likely do exhaust and ECU and therefore headers are kind of icing on the cake.
If there was a good place to do AWD dyno runs in Minneapolis I would volunteer to do before and after headers and then after ECU for comparison purposes.
I am not a big believer in final numbers from chassis dynos but they are a good tuning tool.
I imagine anyone going to the expense of headers would likely do exhaust and ECU and therefore headers are kind of icing on the cake.
If there was a good place to do AWD dyno runs in Minneapolis I would volunteer to do before and after headers and then after ECU for comparison purposes.
I am not a big believer in final numbers from chassis dynos but they are a good tuning tool.
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From: Florida
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I get my TT back on Friday. Got the Mod bug. TA coilovers, TA front lip, TA rear Difusser, TA CF Steering Wheel, Cargraphic Exhaust, Headers, GIAC Reflash, K40, Works CF Intake, 20" HRE 890r(325 rears). Hope to see big gains from the Exhaust, headers, and reflash. Will post pics and opinions Friday.
The Wait Is Killing Me!!!
The Wait Is Killing Me!!!
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