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YOUR RESEARCHIs there any proven performance mods for the 3.4?
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best way of increasing performance
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I like my 3.4 as is and would say that weight reduction is probably the best way of increasing performance on these cars.
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I'd love to see some real world data to back the claims of more power from a different exhaust - at best I suspect you're swapping mid range (useable) torque for a few more peak rpm bhp, which is only any real use on a dyno.
Leading evidence: 'best way of increasing performance' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'best way of increasing performance' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Use on a dyno' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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I'd love to see some real world data to back the claims of more power from a different exhaust - at best I suspect you're swapping mid range (useable) torque for a few more peak rpm bhp, which is only any real use on a dyno.
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Use on a dyno
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Suggestion
I'd love to see some real world data to back the claims of more power from a different exhaust - at best I suspect you're swapping mid range (useable) torque for a few more peak rpm bhp, which is only any real use on a dyno.
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911uk: 1 discussions
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Reading about the IPD plenum upgrade and reflecting over possible performance gains from my Cargraphic exhaust made me think about whats been learned thru the years.
Is there any good reasonable performance bolt ons for the 3.4?
From what Ive read the Cargraphic full system with headders is supposed to give 23bhp and the K/N panel filter (in OEM box) is said about 4bhp. Are these claims bogus or something that has been seen repeatedly in dyno sessions?
Im fully aware of that bolt ons will not convert any C2/C4/C4S to GT3 performance, haha. Just curious about what can be achieved
I like my 3.4 as is and would say that weight reduction is probably the best way of increasing performance on these cars.
Simple answer - No.
There's plenty of companies making claims but I've never seen any real world data to back it up.
Only noticeable option is to get a Hartech capacity increase when the time comes for a rebuild.
....and take an advanced driving course as the weakest link is generally the driver.
I doubt any of us really utilise the maximum that these cars have to offer.... on the roads anyway.
I used to move in Subaru circles years ago and owners were all striving to reach max bhp with remaps, decats etc etc but neglected suspension and brake upgrades and wondered why an impreza sport could keep up with turbos on the twisties......decent driver input and knowledge to me is the best mod one can make to any car.
BHP is for the pub in my book... 300bhp is more than enough for me.
Agree 300 is plenty given our congested roads and the only way to get more power is to increase displacement...
My Son just sold his 991 Turbo S which was way too fast for our roads and his licence
You might find this thread regarding weight reduction of use.
Project C4 Lightweight
Sound deadening needs extremes of temperature to remove most easily. Heat gun (beware toxic fumes) or as others have said, covering it in a layer of dry ice where it will then chip off. Not sure if you've seen this lightweight project...
911uk.com
Within it there's also a link to the ultimate way to achieve performance - ELA's epic CSR thread which culminated in him having a 3.4 with the same power to weight ratio as a 996 turbo.
The 3.4 is 88 bhp per litre specific output, which for a 30 year old design (when they started the project), is pretty good going.
Porsche didn't leave much on the table.
In reality, there is not much to be had by trying to increase the volumetric efficiency - it's pretty much fully developed.
The only way you'll get a material gain in power is to burn more fuel, and to do that you need either an increase in capacity, an increase in revs or forced induction.
Unless you're doing a Hartech rebuild due to necessity where a capacity increase becomes a more efficient 'whilst we're in there' opportunity, you're best leaving well alone.
Perhaps a divisive and controversial comment here, but 7k rpm advertised dyno power increase numbers for high performance exhausts can often come at the expense of useable street driven torque. I have experienced this with mine. Swapping back to standard cats and a quieter exhaust with a little more back pressure unquestionably made the car feel more gutsy in the midrange, with no perceptible difference at the top end.
If it ain't broke..... etc, etc.
YMMV.
Guess it depends on what performance improvement you want to achieve. Is it straight line, feel, lap times etc?
To me the stock suspension setup is compliant and 300bhp is more than enough for UK roads. On a recent birthday I scratched the itch of taking it on a track to open the taps.
First couple of outings I enjoyed the straight line speed, then as I wanted to push on, I found it too soft (compared to my Caterham race car).
Each to their own, but, my conclusion was the stock 996 C2 3.4 is well set up for the road, and any ‘improvements’ for track work would make it worse for the job I use it for. So tomorrow I’ll enjoy driving it to my SIM session…
I'd love to see some real world data to back the claims of more power from a different exhaust - at best I suspect you're swapping mid range (useable) torque for a few more peak rpm bhp, which is only any real use on a dyno.
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