991 Gt3 engine reliability
Discussion
Whilst at Silverstone yesterday, bunch of mates and i started discussing the viability of spending 100+ k on track day toy like the mighty competent 991 Gt3.
There can be no question re it's pace round silverstone and greatness once wound up to its limits.
But, the main contention was always round the fragility of the engine compared to merger and perhaps the newly enhanced and lower rev limit 991 RS.
posts about owners being on 3rd engines abound on internet, whilst the number can't be many, there certainly seems enough of them to cause concern.
I am concerned about constant track usage (like the RSR 991 Gt3) and the toll it takes on the engine. For those that only road drive, this does not concern you (Sidick- pls stay away and do not troll my thread)
Great car but would I not be better served to wait for the 991.2 Gt3 which might get the RS engine with the lower rev limit and presumably porsche motorsport's more intense durability engineering. Haven't heard of 991 RS engines blowing up.
There can be no question re it's pace round silverstone and greatness once wound up to its limits.
But, the main contention was always round the fragility of the engine compared to merger and perhaps the newly enhanced and lower rev limit 991 RS.
posts about owners being on 3rd engines abound on internet, whilst the number can't be many, there certainly seems enough of them to cause concern.
I am concerned about constant track usage (like the RSR 991 Gt3) and the toll it takes on the engine. For those that only road drive, this does not concern you (Sidick- pls stay away and do not troll my thread)
Great car but would I not be better served to wait for the 991.2 Gt3 which might get the RS engine with the lower rev limit and presumably porsche motorsport's more intense durability engineering. Haven't heard of 991 RS engines blowing up.
I'd wait to see if you can get 991.2 GT3 as it's more likely engine issues ironed out by then - Porsche won't want that happening again... If .2 not all it's cracked up to be then IMO 991.1 prices will be lower then anyway so you've not lost anything.
Agree with above on warranty - could be an expensive car to maintain down the road with RWS, tech, engine etc!
Cheers
Slodge
Agree with above on warranty - could be an expensive car to maintain down the road with RWS, tech, engine etc!
Cheers
Slodge
There were stories of GT3 'ring taxis' destroying engines last year but how accurate these were and actually how many cars were affacted in the backlash of the 2 european cars which caught fire due to fuel line connection problems is anyones guess. AFAIK a small number of the early cars had valvetrain issues and received a 'third' engine under warranty.
As already mentioned, only a fool would run a GT3 without warranty and most will benefit from the 'free' fourth year anyway (on the basis the optional cost third year was paid for) but after that it will be interesting to see the annual premium.
I understand the lower 8800 rev limit on the RS engine is nothing to do with 'preservation' following the 3.8 issues.
Agreed the GT4 is a very capable machine at the money especially for rapid road use but perhaps essentially 'flawed' for enthusiasts on track due to obvious lack of fire breathing GT engine.( although many would argue its 'manuel' box more than compensates).
As already mentioned, only a fool would run a GT3 without warranty and most will benefit from the 'free' fourth year anyway (on the basis the optional cost third year was paid for) but after that it will be interesting to see the annual premium.
I understand the lower 8800 rev limit on the RS engine is nothing to do with 'preservation' following the 3.8 issues.
Agreed the GT4 is a very capable machine at the money especially for rapid road use but perhaps essentially 'flawed' for enthusiasts on track due to obvious lack of fire breathing GT engine.( although many would argue its 'manuel' box more than compensates).
Edited by av185 on Sunday 20th March 11:55
HokumPokum said:
Great car but would I not be better served to wait for the 991.2 Gt3 which might get the RS engine with the lower rev limit and presumably porsche motorsport's more intense durability engineering.
Probably good advice, but the biggest risk you face will be the ability to get a car, given the likely massive demand and limited supply (and presuming you don;t want to pay a premium for the car).Regardless of whether the engine issue for the 991.1 GT3 are resolved or not (or would be covered by Porsche on a goodwill basis even if not covered under warranty), there should be fewer concerns with the later car (and a few other updates such as PCM etc). Providing you can get one, which is the key issue you will face.
IIRC they made quite a lot of changes to the GT3 engine for the GT3RS application even though it shares the DFI unit's basic block and bore size - not only the new crank that AP said was made out of 'Star Trek' steel from the 919 lemans hybrid (itself necessitated by the longer stroke of the new engine and therefore the lower topend rpm compared with the GT3), but also new pistons, camshafts, cam springs and a different oil system...so, far from a cosmetic exercise, and I think Hatz went on record as saying that THIS engine would be the basis for other roadcars in the future.
I'm sure the G series version of the 991.1 GT3 engine has already incorporated a lot of what they obviously learned while developing the RS power unit, and this will surely continue, but in detail they would appear to be far from the same.
I'm sure the G series version of the 991.1 GT3 engine has already incorporated a lot of what they obviously learned while developing the RS power unit, and this will surely continue, but in detail they would appear to be far from the same.
hondansx said:
Would be nice to back some of the conjecture with facts.
What is the weakness with the '2nd' engine?
http://www.irishtimes.com/life-and-style/motors/porsche-gt3-owners-face-more-engine-concerns-1.2284524What is the weakness with the '2nd' engine?
Article says - The original engines were found to have an issue with a loosened screw joint on the piston connecting rod, though Porsche sources have said the latest engine problem is in the valvetrain of the flat-six motor and it was less troublesome to simply remove the engines and replace them with all-new motors.
I know of 1 definite 3 engine car. The 2nd engine was replaced due to a 'valve-train' related issue and my customer then sold the car as he lost faith in the product.
I have other customers who have had no issues whatsoever including one who has done many track days including over 50 laps of the Ring at serious pace - so much so that he was the first person in the UK who has ever ordered a replacement set of 'REAR' pads for the PCCB from Porsche. His OPC said they had supplied a few sets of front PCCB pads (2 sets to him!) but Porsche UK had never sold a set of rears.
I have other customers who have had no issues whatsoever including one who has done many track days including over 50 laps of the Ring at serious pace - so much so that he was the first person in the UK who has ever ordered a replacement set of 'REAR' pads for the PCCB from Porsche. His OPC said they had supplied a few sets of front PCCB pads (2 sets to him!) but Porsche UK had never sold a set of rears.
chrisABP said:
I know of 1 definite 3 engine car. The 2nd engine was replaced due to a 'valve-train' related issue and my customer then sold the car as he lost faith in the product.
I have other customers who have had no issues whatsoever including one who has done many track days including over 50 laps of the Ring at serious pace - so much so that he was the first person in the UK who has ever ordered a replacement set of 'REAR' pads for the PCCB from Porsche. His OPC said they had supplied a few sets of front PCCB pads (2 sets to him!) but Porsche UK had never sold a set of rears.
I have PCCB on my 997.1 GT3 and as a rule I change the pads when they get to around 50% worn. I understand this is good practice as it keeps the heat transfer down and also if you let the pads go any lower than 50% worn there is a chance they can score the disc and then its ££££££ I have other customers who have had no issues whatsoever including one who has done many track days including over 50 laps of the Ring at serious pace - so much so that he was the first person in the UK who has ever ordered a replacement set of 'REAR' pads for the PCCB from Porsche. His OPC said they had supplied a few sets of front PCCB pads (2 sets to him!) but Porsche UK had never sold a set of rears.
This is a great thread for anyone asking some questions etc..Macca on here has been very helpful detailing all issues etc.
http://rennlist.com/forums/991-gt3-gt3rs-and-911r/...
http://rennlist.com/forums/991-gt3-gt3rs-and-911r/...
Quoted here for future reference......
Having a chance recently to examine an E series GT3 engine during strip down for cam shaft and rocker finger renewal I can confirm first hand the issue is not the camshaft nor the crankshaft in these engines (not yet heard of any weaknesses with the crankshaft) but indeed the oiling to the far end of the block (Cylinder 6). The DLC coating on the finger rockers appears to show accelerated wear on the inlet side (more so than exhaust side). The new G series GT3 engine is based on the GT3RS engine with a different oil filter, larger filter neck and updated oil pump and software flash which increases mid range oil pressure. One assumes the damage to the finger rockers is occurring at high rpm (8000+) however that is at the moment only a guess. Once the DLC coating has worn through on the lower foot of the finger lifter the cam lobe starts to score. The ECU identifies the timing issue created by the fine change in tolerances on the affected bank and throws a check engine code.
From the limited access I have to second hand information from the Porsche Motorsports team running the 9A1 program it would seem that they also experiences far bank lubrication challenges in making the engine durable.
The camshafts will change profile for the 9A1 MA race engine to suit where the power is best made. The same applies with displacement changes etc (i.e. 3.8 to 4.0). The camshafts are not t blame. The crankshaft is beefed up to handle the extra power/abuse the 4.0L engine will receive.
Having a chance recently to examine an E series GT3 engine during strip down for cam shaft and rocker finger renewal I can confirm first hand the issue is not the camshaft nor the crankshaft in these engines (not yet heard of any weaknesses with the crankshaft) but indeed the oiling to the far end of the block (Cylinder 6). The DLC coating on the finger rockers appears to show accelerated wear on the inlet side (more so than exhaust side). The new G series GT3 engine is based on the GT3RS engine with a different oil filter, larger filter neck and updated oil pump and software flash which increases mid range oil pressure. One assumes the damage to the finger rockers is occurring at high rpm (8000+) however that is at the moment only a guess. Once the DLC coating has worn through on the lower foot of the finger lifter the cam lobe starts to score. The ECU identifies the timing issue created by the fine change in tolerances on the affected bank and throws a check engine code.
From the limited access I have to second hand information from the Porsche Motorsports team running the 9A1 program it would seem that they also experiences far bank lubrication challenges in making the engine durable.
The camshafts will change profile for the 9A1 MA race engine to suit where the power is best made. The same applies with displacement changes etc (i.e. 3.8 to 4.0). The camshafts are not t blame. The crankshaft is beefed up to handle the extra power/abuse the 4.0L engine will receive.
v8ksn said:
Quoted here for future reference......
Having a chance recently to examine an E series GT3 engine during strip down for cam shaft and rocker finger renewal I can confirm first hand the issue is not the camshaft nor the crankshaft in these engines (not yet heard of any weaknesses with the crankshaft) but indeed the oiling to the far end of the block (Cylinder 6). The DLC coating on the finger rockers appears to show accelerated wear on the inlet side (more so than exhaust side). The new G series GT3 engine is based on the GT3RS engine with a different oil filter, larger filter neck and updated oil pump and software flash which increases mid range oil pressure. One assumes the damage to the finger rockers is occurring at high rpm (8000+) however that is at the moment only a guess. Once the DLC coating has worn through on the lower foot of the finger lifter the cam lobe starts to score. The ECU identifies the timing issue created by the fine change in tolerances on the affected bank and throws a check engine code.
That's really interesting, which raises a few questions:Having a chance recently to examine an E series GT3 engine during strip down for cam shaft and rocker finger renewal I can confirm first hand the issue is not the camshaft nor the crankshaft in these engines (not yet heard of any weaknesses with the crankshaft) but indeed the oiling to the far end of the block (Cylinder 6). The DLC coating on the finger rockers appears to show accelerated wear on the inlet side (more so than exhaust side). The new G series GT3 engine is based on the GT3RS engine with a different oil filter, larger filter neck and updated oil pump and software flash which increases mid range oil pressure. One assumes the damage to the finger rockers is occurring at high rpm (8000+) however that is at the moment only a guess. Once the DLC coating has worn through on the lower foot of the finger lifter the cam lobe starts to score. The ECU identifies the timing issue created by the fine change in tolerances on the affected bank and throws a check engine code.
How 'dangerous' is the issue? Once you get the warning, will a trip to your OPC and new rockers resolve it or is the scoring already present at that time?
Presumably the cost of the parts is relatively low, but the labour charge (if not under warranty) would be very high?
Presumably they can update the software for the non-RS engine too, if considered necessary?
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