What Octane rating is recommended for '77 911 Carrera 3.0???
07-12-2002, 11:49 AM
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What Octane rating is recommended for '77 911 Carrera 3.0???
I'd like to know what octane rated fuel others might be using for their 911's.
I understand that it was recommended that a rating of atleast 91/92 was used this equated to std unleaded fuel. While a lead replacement fuel is approx 95 and premium fuel is approx 97/98.
Obviously the higher you go the more expensive it is, but does it make a marked difference? Does the car need to be tuned differently to take advantage of this fuel?
Will I be wasting money using a higher rated octane than the regular 91/92?
Any help would be appreciated.<a href="http://www.owners-gallery.com/gallery.asp?sort=0&userid=593" target="_blank">The Porsche owners Gallery</a> <img src="graemlins/yltype.gif" border="0" alt="[typing]" />
I understand that it was recommended that a rating of atleast 91/92 was used this equated to std unleaded fuel. While a lead replacement fuel is approx 95 and premium fuel is approx 97/98.
Obviously the higher you go the more expensive it is, but does it make a marked difference? Does the car need to be tuned differently to take advantage of this fuel?
Will I be wasting money using a higher rated octane than the regular 91/92?
Any help would be appreciated.<a href="http://www.owners-gallery.com/gallery.asp?sort=0&userid=593" target="_blank">The Porsche owners Gallery</a> <img src="graemlins/yltype.gif" border="0" alt="[typing]" />
07-12-2002, 12:51 PM
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Hi,
I have a 3.0l Carrera as well and short answer yes you should be filling up with at least Premium Unleaded in those cars but preferably the Optimax/Synergy/BP Ultimate style fuel.
The reason is simple. Porsche specified a minimum 91 rating in US fuels rating which is actually CLC. (RON + MON / 2 - US Cost of Living Council method).
91 CLC is 95 in Australian RON. 95 is equal to Premium unleaded in Australia - however - the 3.0L Carrera engine was designed to run in Australia on Super Leaded Petrol.
Super has a RON rating of 98. The only thing that matches that is Optimax/Synergy/BP Ultimate which also have octane ratings of 98 (Vortex by Caltex is only 96 RON).
You shouldn't have a catalytic converter on your car so there are no issues as far as posioning it is concerned. Also, 98 RON will mean you won't have detonation happening, and all sorts of other issues that you might have have running standard unleaded.
I can sometimes get pinging with the slightest advance on Premium unleaded, under Synergy I never have a problem.
Stick to Synergy/Optimax/BP Ultimate and you won't have a problem.
As far as vavle seat lubrication is concerned, apparently Porsches are fine and don't need an additive when running 98 RON, although Shell do recommend the use of a Valve Seat protectant additive every three tanks....
Remember, the fuel quality in Australia is not the best. We are still not up to par with most of the rest of the world.
I have a 3.0l Carrera as well and short answer yes you should be filling up with at least Premium Unleaded in those cars but preferably the Optimax/Synergy/BP Ultimate style fuel.
The reason is simple. Porsche specified a minimum 91 rating in US fuels rating which is actually CLC. (RON + MON / 2 - US Cost of Living Council method).
91 CLC is 95 in Australian RON. 95 is equal to Premium unleaded in Australia - however - the 3.0L Carrera engine was designed to run in Australia on Super Leaded Petrol.
Super has a RON rating of 98. The only thing that matches that is Optimax/Synergy/BP Ultimate which also have octane ratings of 98 (Vortex by Caltex is only 96 RON).
You shouldn't have a catalytic converter on your car so there are no issues as far as posioning it is concerned. Also, 98 RON will mean you won't have detonation happening, and all sorts of other issues that you might have have running standard unleaded.
I can sometimes get pinging with the slightest advance on Premium unleaded, under Synergy I never have a problem.
Stick to Synergy/Optimax/BP Ultimate and you won't have a problem.
As far as vavle seat lubrication is concerned, apparently Porsches are fine and don't need an additive when running 98 RON, although Shell do recommend the use of a Valve Seat protectant additive every three tanks....
Remember, the fuel quality in Australia is not the best. We are still not up to par with most of the rest of the world.
