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YOUR RESEARCH997 gt3 3.9 engine build - Page 1 - Porsche General - PistonHeads UK
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Set another three seasons
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Suggestion
and I know of GT4 Clubsports that have been raced over three seasons and when stripped were simply re-built with new bearings etc, all set for another three seasons ???
997 gt3 3.9 engine build - Page 1 - Porsche General - PistonHeads UK
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Leading evidence: 'Set another three seasons' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Set another three seasons' (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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Suggestion
I’m aware of 3.6 -> 3.8 and 4.0 conversions using Porsche parts, but not 3.9.
997 gt3 3.9 engine build - Page 1 - Porsche General - PistonHeads UK
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Set another three seasons
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Suggestion
and I know of GT4 Clubsports that have been raced over three seasons and when stripped were simply re-built with new bearings etc, all set for another three seasons ???
997 gt3 3.9 engine build - Page 1 - Porsche General - PistonHeads UK
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Would love to hear more detail about your build! Also what made you go for this conversion with them? Is it a repair or just want more power for instance? I’m aware of 3.6 -> 3.8 and 4.0 conversions using Porsche parts, but not 3.9. What internals / parts are you using?
Capricorn I’d imagine, in a Gen 1 3.6 motor.
It’s a cost effective upgrade that without any other mods should liberate 440hp and maybe a bit more. With cams & exhaust mods, closer to 470-480.
Their early 3.9 conversions were “problematic”, Manthey amongst others used them, but they seem to have sorted the various issues out.
There are other options, notably Mahle, but the last I heard, availability was an issue, and the costs eye watering, but if you want to keep things more OE and go 4.0, it would be Mahle 3.8 pistons with an OE 4.0 crank.
Thanks guys will keep you updated,the reason for conversion was that the engine was completely worn and rebuilding was more cost effective than a new motor
Slippydiff said:
Capricorn I’d imagine, in a Gen 1 3.6 motor.
It’s a cost effective upgrade that without any other mods should liberate 440hp and maybe a bit more. With cams & exhaust mods, closer to 470-480.
Their early 3.9 conversions were “problematic”, Manthey amongst others used them, but they seem to have sorted the various issues out.
There are other options, notably Mahle, but the last I heard, availability was an issue, and the costs eye watering, but if you want to keep things more OE and go 4.0, it would be Mahle 3.8 pistons with an OE 4.0 crank.
How far would you go chasing max power over temperament and longevity ?
The GT3 Cup engines are lifed ... the GT4 Clubsport engines are not ... and I know of GT4 Clubsports that have been raced over three seasons and when stripped were simply re-built with new bearings etc, all set for another three seasons ???
Great project! Sharkwerks have built loads of 3.9 997 GT3s in the USA, along with some 4.1 Gen2 cars
https://www.sharkwerks.com/projects-mf_gt3-rs-r_g_...
They are meant to be a lot of fun!
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