Fuel/Gas/Petrol for 383 69RR

[Brendanchambers]

I know this has been probably thrashed out many times.....so this question is mainly for my Australian friends.....as we don't get the same gas you do in the USA

What fuel/gas/petrol (depending where ya from) should i run in my 69 RR with the 383HP....

i'd like to think i can just run a 98RON (93 octane for USA)....or do i need an additive...

My brother has a 65 mustang with a very original engine, he uses an additive however its only becuase the old 289 runs pretty rough and he's worried that if he doesnt run an additive it may be even worse..


any advice would be handy, i dont want to wreck something by using the wrong fuel.

 

[4mulas]

You’re fine with the 98 RON. Premium pump gas in Canada is 91 octane, and a few dealers have no ethanol in their blend which is what I look for. Mine runs just fine on that and the compression ratio is slightly higher than that of a stock 383 HP. There is also a 94 octane available here that I haven’t used before as it has a bit of ethanol in it.

If your valve seats aren’t hardened you may want an additive for extra lubrication in the fuel that lead used to provide. But if your like most of us over here that don’t use the cars very much it really isn’t an issue anyway due to minimal use.

Spent some time over your way and now I’m craving a Newcastle brown.!

 

[Ranger16]

i'd like to think i can just run a 98RON (93 octane for USA)....or do i need an additive...

That's what I run in mine with NO additives.

 

[1967coronet]

93 should be good , all depends on compression , engine.
If your not pinging under load you should be fine ,
Read the plugs.
If you have a little detonation back off the timing a little bit until the ping is gone.
Or mix fuel.

 

[Brendanchambers]

Ok, thanks.

will just run 93 octane (98RON) and see how it goes, if it pings i will try additive...