More BAD Optimax Facts

[BOOSTMEISTER]

I was talking to Richard from www.are.com.au the other day and he told me something that is a bit disturbing....

He has a R33 gtst that he has been working on and finally got it back on the road. Took it to the dyno and made a power run, the result was a bit dissapointing and they were trying to figure it out when the guy asked Richard what fuel he was running. "Optimax was the last fuel put in the car" Richard replied, "When was that?" the dyno opperator asked, "About 2 weeks ago". the dyno opperator then explained that Optimax is only good for about 1 week then its RON rating starts to fall. So he tipped in some octain booster and then ran the car again and made just under 20rwkw EXTRA once the RON got back up. This explains why on a number of occasions after doing a couple of weeks work on my car the dyno runs have been down on power and the car detonates easilly.

Cam

[akira]

Does anyone know if PULP ( all brands ) start 2 go off after a week or so.I've tried all 3 brands and am tossing up between BP ultimate and Optimax. What do you reckon guys?

[BOOSTMEISTER]

PULP [Premium Unleaded Petrol] is different to Optimax and Ultimat as it has a lesser RON that these other fuels.

It seems that the consensus is that BP Ultimate is better than Shell Optimax and even tho it all comes from the same place BP & SHELL have it mixed to their own specs and it seems that BP is better at producing consistant RON readings and lasts longer at a higher RON.

Cam

[gsi]

I've had problems with optimax twice now...I've found it more to do with the actual petrol station than the optimax itself...

The shell on para rd, just past stanmore maccas is the worst!

Do not buy from there...I know plenty of people that have had bad fuel from there...I've had to have my system completely flushed and my injectors ultrasonically cleaned coz of them!

[Guest Miguel]

I just used BP Ultimate for the first time last week, and by my seat-of-hte-pants testing, I feel that Optimax is better. I'm sure I heard some slight pinging with the Ultimate at higher revs.

That said, I know of an Evo & an Sti that required rebuilds due to some sludgy residue left in the fuel filter and Optimax was deemed responsible.

[U WERE MINE]

my car runs really bad on bp.. ?? on optimax tis all sweet

[john]

ive got r33 and have always run ultimate, is it worth putting in an octane booster as well or is that just too much. if i do put in a booster as well is the timing sweet how it is?

[two40]

  Quote

even tho it all comes from the same place BP & SHELL have it mixed to their own specs[/quote:11d9cb0e09]

isn't BP the one who produces all the PULP, and then as you say they all mix in their additives?

[Guest Miguel]

  Quote

ive got r33 and have always run ultimate, is it worth putting in an octane booster as well or is that just too much. if i do put in a booster as well is the timing sweet how it is?[/quote:bc23bd7840]

I find with Octane booster & Optimax, my car revs much more freely, it doesn't feel restricted up high. I spose with a higher octane rating, you could fiddle with the timing if you wanted to, to get even more out of it

[john]

what octane is optimax

[two40]

john, the RON rating for most premium unleaded fuels including optimax is 98. this is the highest legally allowed RON for street use.

Racing fuel

c-10 104

c-12 110

c-14 116

c-14+ 117

c-15 117

c-16 118

c-18 116

[meggala]

where can you get these c grade fuels in unleaded cause I cant see vp haveing unleaded high octane but I could be wrong.

meggala

[two40]

steve, all the vp fuels with a high ron do contain lead which is a shame. i'm sure the cat or your oxygen sensors will not like you using these fuels at all.

don't quote me but i remember hearing that c-10 is ok to use. again, don't quote me.

i posted the vp's as a point of reference for john.

[51jay]

My understanding is PULPS are a minimum 96 Optimax is up to 98 and BP Ultimate is minimum 98

lots of people seem to be confused about PULP and the higher rated fuels

Optimax and Ultimate are not PULP

[two40]

  Quote

Optimax and Ultimate are not PULP[/quote:da32e47ddc]

'course not. BP manufactures the pulp and sells it to everyone as a raw product. they in turn mix their additives which make it 98RON. it's like you putting in an octane booster in with your fuel but way more technical

it just makes cars more resistant to detonation, that's all.

[Neil]

We have been using Optimax since buying the car last September and never had it ping and I Snot it big time!!!!. I really do give it a hard time.

We are standard apart from 5 Zigen cat back. We have used an Octane booster once and could see no difference at all,,, actually we used it on the Canberra run. I have used the Synegy once and it was no better, then again it didn't ping either. After doing some checking,,,Mobil says there's is guaranteed 98 and Shell is around 96....Stuffed if I know,,,,but I'm sticking with Shell at the moment.

We have a station 5 minutes away and racing the guy next door with his Commadore running 350kw's at the treads on full tanks is a ball. You can hear me now,,,Get out of my way you sideways dickhead.....What you can't stop,,whats wrong buddy,,,Oh thats right is a Holden.

Neil.

[two40]

  Quote

We have been using Optimax since buying the car last September and never had it ping and I Snot it big time!!!!. I really do give it a hard time. [/quote:b3222afdc9]

Neil, your car has definately pinged, you just don't realise it.

Unless you have a sensor you can't really tell how much detonation goes on.

[Shell]

I have always used Optimax and never had any problems, but lately I've been using BP (only because it's easier to find at 2am on my way home). Haven't noticed any difference.

Whatever's closest will do me

[Neil]

Nah Onarun,,,,I think,,, at my ripe old age I know if she's pinging or not. I don't think I really need a gauge to tell me that,,,turning the stereo off and listening to her reving to full song under load is enough evidence for me. Remember I'm basically stock,,,which means tons of fuel. I'm with you Shell,,,,the Mobil is also only down the road,,, used a tankfull last week and noticed no difference. My ultimate test will be tomorrow night when I get my neibour with his hot Commadore using Mobil..............

Oh and by the way,,,,,C10 and Cats/02 probe/Cat Heater are like,,,,shit I hate you and I'm gonna stuff you up big time. Don't use it!!!!!.

Neil.

[Guest Boxhead]

whats the best way to change over to bp ultimax....

should i run down the tank of petrol totally? and fill up? or is ther eno hope.. and i shoudl stick with normal unleaded