Some details on 9A1 engine in GT3R
#1
Three Wheelin'
Thread Starter
Some details on 9A1 engine in GT3R
The latest issue of Christophorus states that the engine in the GT3R is based on the 9A1 in the RS. Allegedly it pumps out 500 hp (same as the RS) but with higher torque (figure is unspecified). The engine has new bearings for the crankshaft, a new tuning for the intake camshaft, and a new control unit designed for racing. A heady 9500 RPM limiter figure is quoted.
I do not know how comprehensive is the description in the article. One can speculate that if these are the extent of the changes that the engine is then quite close to those in the GT3/RS cars. That said, however, one must wonder how much has been left unsaid.
It is interesting to note that the changes mentioned deal with both the crankshaft and camshaft. There has been a lot of discussion about these two being weak points of the GT 9A1 engines. Maybe these changes in fact confirm that those are real weaknesses and not just unfortunate issues.
A good article on the car itself starts on page 88 of the issue.
Daytona is close. I guess we will hear more soon.
I do not know how comprehensive is the description in the article. One can speculate that if these are the extent of the changes that the engine is then quite close to those in the GT3/RS cars. That said, however, one must wonder how much has been left unsaid.
It is interesting to note that the changes mentioned deal with both the crankshaft and camshaft. There has been a lot of discussion about these two being weak points of the GT 9A1 engines. Maybe these changes in fact confirm that those are real weaknesses and not just unfortunate issues.
A good article on the car itself starts on page 88 of the issue.
Daytona is close. I guess we will hear more soon.
#3
Rennlist Member
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.
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.
#4
Three Wheelin'
Interesting info Macca. Much appreciated. Great insight as to the issue. Has there been any recommendation for the 2014,2015 GT3 E series engine owners? And what happens when one needs replacement? Do they use the new design?
Also.... Any thoughts to the 9500 redline stated in that article for the GT3R? One would think more than 500 hp would be generated if an additional revs are added.
Also.... Any thoughts to the 9500 redline stated in that article for the GT3R? One would think more than 500 hp would be generated if an additional revs are added.
#5
So when are they revealing this wingless unicorn?
#6
Race Director
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.
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.
#7
Three Wheelin'
Thread Starter
Tanks Macca, great insight. Any idea why the diamondlike carbon coating is wearing off? I guess the idea of the coating is precisely to prevent that. Is the oiling that bad? Is it possible that as mileage accumulates over time, maybe not just high RPM, that those not tracking will face the same or similar issues?
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#8
Addict
Rennlist Member
Rennlist Member
#9
It might be speculation but it sounds like they have changed something because they would have had the standard (old?) GT3 filters. They did anyway when I changed the oil in the 3.
#10
I recently had the Oil optimisation ECU update done on my late 15 F build car.
Do you think Porsche will allow us to upgrade these components to match that of the G engines: "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. "
Do you think Porsche will allow us to upgrade these components to match that of the G engines: "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. "
#13
#14
Drifting
Great info