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YOUR RESEARCHx51 powerkit for 99 carrera
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Replace camshaft, exhaust manifold, headers and ecu while leaving
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Suggestion · Original poster
just replacing the camshaft, exhaust manifold, headers and ECU while leaving on the stock heads.
Leading evidence: 'Replace camshaft, exhaust manifold, headers and ecu while leaving' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Replace camshaft, exhaust manifold, headers and ecu while leaving' (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
One with hydraulic and one using solid lifters (same durations/overlap):
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Has anybody retrofitted an x51 kit on their 99 C2? I'm curious to know what the results are vs. just replacing the camshaft, exhaust manifold, headers and ECU while leaving on the stock heads.
I'm thinking about a 40HP gain with X51... I know they claim 25 but porsche is always conservative...
Remember the 3.6 x51 is different than the 3.4 x51 kit, check it out, but I'm pretty sure I'm right. DJ996 looked into this a while back maybe he or jimB will chime in.
The 3.4L X51 was never sold in the US so it was never Certified for the US emissions. The kit may pass the sniffer test, but the parts are not certified, but many smog shops probably won't know if the parts are not certified. As far as what to expect from aftermarket kits of cams, cats, headers, ecu the total power gain is about 35HP at best. Its really not worth the money you will spend on it, but if you were to do the X51 which probably gain an extra 10 HP over aftermarket stuff would cost more.
I think the biggest bang for buck in the kit is the cams.... may do just the cams alone and re-map the computer to work with the cams.... I hear that's good for another 20HP and 20Ft-lb and the remap may give you another 10 or so...
I agree the price of X-51 is high - it's OEM porsche but wondering how much the cams and computer re-map will cost on their own.
Any guesses on labor to re-cam? I looked in an '03 RoW PET, and no X51 cams were listed for the 3.4L. They did list X51 cams for the 3.6L. Intakes only, it appears. Anyone use tuner cams? TechArt made some at one point and also Schrick.
ask Jimb - he has it on his race car.
I'm not sure about the EPA stuff but i thought it was sold in the US but very rare due to it's 10K cost- dunno could be wrong there and it was just sold with the 3.6L
There was a "Carerra Powerkit" available in the Tequipment catalog in 2001 for the 3.4 engines but it wasn't called X51 at that time. I looked into this at the time and the cost from the dealer was $10k for parts alone. The powerkit specs were increase from 221 kw to 235kw. There was a Porsche part number for the kit and the dealer would install. I never asked the labor cost...$10k for 20hp was way to steep to dump into my 99 at the time. Still is.
Interesting reading:
http://www.pca.org/tech/tech_qa_ques...E98AF37E07C%7D
about the "Carrera Power Kit".
Also, Schrick has 2 versions of cams for the 3.4L. One with hydraulic and one using solid lifters (same durations/overlap):
http://www.greenspeed.be/common/Schrick%202005%20E.pdf
Page 14 and 15. Wish I could find stock specs.
I like the idea of dropping in a GT3 motor.... seems the powerkit option is very $$$$... I mean what would be the total cost of buying and installing GT3 motor vs retrofitting X-51...parts?
Doing the rebuild seems quite complex and you would need a master craftsman to do it for you... is there anybody in Canada or North Eastern USA who has done these 2 upgrades before?
This is a source reference. Confirm exact model applicability in the original material.
