I've noticed that the GT feels a bit 'sluggish' sometimes (relatively speaking) in that it is not as responsive down low and that it lacks a little at the top end. Then at other times the opposite happens. I never quite knew what to make of this until I paid attention to what fuel I had just filled it with. My practice is that I drive it until the fuel warning light comes on and it is nearly empty before fully filling the tank. I accept that my observations may well be incorrect as I am only going by the bum dyno, but I am of the firm belief that the type of fuel you use affects the power and responsiveness of the motor.
I only use 98 RON fuel and I have noticed that the Mobil premium unleaded seems to give the best performance. I recently filled it with another brand of 98 RON to test my theory. I noticed that the performance of the engine seemed to reduce. I then went back to the Mobil when the tank was nearly empty and the power and responsiveness returned.
I am very interested if any other Boss 290 owners have noticed the same or am I just imagining this?
It seems that the best two fuels to use are Shell Helix and Mobil Premium,i generally use the Shell Helix but i might give the Mobil one a try from now on and see how it compares,Peter from APS also recommends these two Fuels.
Cheers John
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We have mobil premium here at some servos and mobil synergy 8000 at most of the other mobil outlets. My GT runs like a dog on the premium but flies on synergy or optimax...
Well, I dont have a GT (yet) but I can say that I will only use Mobil 8000 in my XR6 given a choice. Otherwise I will use BP. I wont use shell at all if I can avoid it, I've found it is inconsistant to say the least.
We have mobil premium here at some servos and mobil synergy 8000 at most of the other mobil outlets. My GT runs like a dog on the premium but flies on synergy or optimax...
When i was talking about Mobil Premium what i really meant to say was Mobil synergy 8000.
Cheers John
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If you have an XR6, XR8, T-Series or FPV vehicle (GTs) why not join.
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Mate I see you are in Geelong. The Mobil 98 ron synergy fuel is processed in Victoria and is the most consistent premium fuel in Victoria, the shell optimax (produced in a Sydney refinery only) also works well in most modern 4 valve engines (not bike engines from what I'm told).
I would steer well clear of the B* premium (refined in QLD and WA only) in my experience it is no where near as good as the Mobil or Shell 98 RON premium unleaded fuel in high comp 4 valve engines.
Mate I see you are in Geelong. The Mobil 98 ron synergy fuel is processed in Victoria and is the most consistent premium fuel in Victoria, the shell optimax (produced in a Sydney refinery only) also works well in most modern 4 valve engines (not bike engines from what I'm told).
I would steer well clear of the B* premium (refined in QLD and WA only) in my experience it is no where near as good as the Mobil or Shell 98 RON premium unleaded fuel in high comp 4 valve engines.
Peter
APS
Peter if you lived in W.A what would you use?
Ive only ever used the BP Oltimate 98.... in my GT-P and before that i used it in my T3..
Mate I see you are in Geelong. The Mobil 98 ron synergy fuel is processed in Victoria and is the most consistent premium fuel in Victoria, the shell optimax (produced in a Sydney refinery only) also works well in most modern 4 valve engines (not bike engines from what I'm told).
I would steer well clear of the B* premium (refined in QLD and WA only) in my experience it is no where near as good as the Mobil or Shell 98 RON premium unleaded fuel in high comp 4 valve engines.
Peter
APS
I've found this to be correct, opti can be inconsistent, but every tank of synergy was excellent, also, a minor issue, having a fleet card for fuel, negates you from getting 4c/litre disc on shell opti also no fly buys, insignifigant you say, well it equals around $250 bucks a year on $4000 worth
of fuel, so I'll make a point of buying Mobil. No discrimination there.
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Ive only ever used the BP Oltimate 98.... in my GT-P and before that i used it in my T3..
I've been told by tuning friends in the west that the BP ultimate (REFINED IN WA) is best premium unleaded fuel in West Australia. I do believe this to be true, though from my own experience the B* ultimate in Melbourne is not very good compared to the 98 RON Mobill Synergy fuel.
Hi Peter,
I was just wondering wether you guys have done any tests with octane boosters on the BOSS motor or any other modern motor?Was there any improvement in power across the range.I haven't bothered trying this on the track but in future might give it a go.I have a Clevo with a few ponies and use a octane booster only for the octane rating but have found it not to make any difference in power in this instance.Just wondering if the modern type motors would benefit with the extra octane as the computer adjusts itself to the better octane level?
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