What is the best fuel for my Z

[Rusty1]

Hi guys, can any Oz zed owners advise me please on the best fuel to run in my stock 260z. I have recently bought it and the previous owner used Optimax, I do not wish to do this as it has been known to destroy carb gaskets. Please help.

[Gav240z]

Dunno about optimax destroying gaskets maybe the cleaning agent inside it might cause it to deteriorate them dunno I've run optimax with my Z on Su carbs no problems so far.

A stock 260z wouldn't require a high octane I think the manual says 88 octane and up.

However if your valve seats are brass(notsure) you might wanna use a lead or lead substitute however if your Z has done high KM's then you will need to rebuild the engine within the next few years anyway and therefore it won't make a difference till then.

Lead substitute is a joke in Australia.

You can run normal unleaded but you'll probably loose some power.

Stick with optimax or premium.

[Rusty1]

Thanks for you help. Firstly, how long have you been running Optimax in your engine?

Secondly, you are not the first person to criticize Australian lead substitute petrol, nobody has been able to tell me what the problem is with it. Can you advise.

[Gav240z]

A few reasons really the first is that the substitute they put in for the lead isn't all that good. Second it's not as powerful as the old leaded fuel was and third because it's overpriced and really no better than normal leaded fuel.

I have been running the car on optimax for more than a year and it definately runs better than premium fuel.:classic:

[That Ozzy Guy]

Hey Rusty, welcome to the friendliest forum on earth. Money back guaranteed.:classic:

Gav, just to throw some fuel on the fire (pardon the pun) Optimax has had some weak results for some time now. Many people advise staying away from it. I can only think of two reasons for this;

1. There was a bad batch in Sydney so it got a bad rep quickly spread on forums.

2. It really has dropped of in quality and Shell is riding it for all it's worth through their strong advertisement program.

It is widely known that one fuel works great in one car while it pings in another so what some people have experienced does not ring true for others. For this reason I don't take much stock in what people recommend. Just try all the fuels and see what works for you.

Whatever the case might be I haven't used it for a long time now. I stick with BP Ultimate and it works for me. I know the PULP they use is pure (at least I hope so) and not riddled with too many additives.

[260Zed]

Ive run standard unleaded and primium occasionally (bout every fourth tank) and havent experienced any problems/pinging. Thats a e88 head with round tops and a mild cam.

I've also heard that lead replacement isnt that great, for the reasons stated above.

Also be wary of independant suppliers and the quality of fuel they provide. They can import fuel from SE asia and (believe it or not) Kazakhstan, which both provide a lower quality fuel than our traditional suppliers.

Maybe a saving a few cents at the pump mite equate to a lot more money in solving engine trouble down the track! :dead:

[tanny]

In the states, often different retailers will get gas from the same refinery, the only difference being the additive package they put in afterwards. A friend of mine owned the Texaco and now the Exon gas stations in my area. Just a footnote. Victor.

[Rusty1]

Thanks for all of your advice guys, it looks like I have some homework to do.

[240Zdragon72]

I'd run midgrade maybe for a couple of weeks the switch to premium and see if their is a significant change.

[Gav240z]

Oh George is correct I've found that BP Ultimate had made my high comp E88 F54 blocked 240z run the best. I had major pinging problem but i put this down to a faulty module on my electronic distributor.

I have a new distributor, and soon a new E88 head with larger camshaft profile wanting to see how this goes . I will also see how smooth the chamber is etc to see if this was causing any knocking although this would be more of a problem in a turbo motor.

Let ya know.

[TomoHawk]

I've been using several different grades of gas, but usually from the same place if I can. In my Escort, the 89 octane seems to work best (mileage & power.) But in the 280Zed, I haven't noticed much difference between the 89 or 92 octanes. BTW, I usually only get about US$5 worth, so I can flush out all the rust from the gas tank:o

I didn't even know you could use leaded fuel in the Zed, there's no warning sticker anywhere in there, or the usual places. Would it be good to try some lead?

[Gav240z]

You have a 280z with steel valve seats the early L24's and L26's mainly had the brass ones.

The l28 came with hardened valve seats .

I know it's illegal to run a unleaded car with lead in Australia dunno about the states.:cheeky: