What fuel to use with high comp 4age

[ChaosAD]

Ive got a rebuilt 16v bluetop 4age with a compression ratio of about 11:1 - 11.5:1 that will be running the standard ecu for the time being.
What sort of petrol and ignition timing should I be running on it.

Would 98 and slightly retarded timing be enough? or 96 with octane boost?
Or will I need to get my hands on some avgas? could be a problem though as I dont have a motorsport license yet.

What do you guys reckon?

[atmosports]

98 should work fine, think of four stroke motorbikes ect alot of them run similar compression on 96/98 pump gas. Else if it was a competition only car you could use the like of c12/c16 or equivalent from Elf etc but it's usually more than the cost of avgas & harder to get, but can be used on the road, well the unleaded stuff, still not paying road tax on it though.

[ChaosAD]

Turns out 98 is anavailable north of Auckland.
I doubt 96 with octane boost will be sufficient, so ratio of av/96 should I run?
or if it will run with 96 and octane boost, how much should I retard the timing?

[atmosports]

Without putting the car on a dyno with a decent knock setup & checking for detonation it's hard to say. We've run some hi compression Hondas on 98 without anythig else & got good results but really it comes down to the individual engine & who/how it's been put together.

[solberg Fan]

Or will I need to get my hands on some avgas? could be a problem though as I dont have a motorsport license yet

Dont need a licence to get it. But it cost about 1.80 a Ltr and is illegal to run on the road (so every one tells me..).

[Dragger_Dan]

I think that the airport will sell avgas to the public. I know some speedway guys get it there. Have you tried Gull with octane boost? Gull petrol is race gas compared to most stuff from the usual petrol stations.

[Crampy]

Why does everyone still say that about Gull fuel. When Gull first came in it was very good, because it's first shipment was a good batch. It changed supplier shortly after and it's pretty much the same as all the other crap we get in NZ...

[Dragger_Dan]

I can give you one excellent example: My dad owns (among other things) a 1965 Morris 1100. If you fill up anywhere but Gull, the car won't run right... ie missing, bit of ping etc. If you put gull in it, it runs fine, even without lead additive. So Gull is better, it's just most people don't notice it cause their jap car is tuned for shit gas anyway. Also Gull gas leaves less residue or garbage in your fuel system. We actually tested this at a chemistry seminar. It is better, and it doesn't cost any more than anywhere else.

[Lloyd]

The lead additive doesn't have anything to do with how well the car will run

[vvega]

its not a lead aditive its basically kero and some airomatics
lead raises the knock point of the fuel......

im done for the night

v