Avgas

Anyone ever run AVGAS 100 or 100LL in their Dauntless? Seems to me like the properties of the AVGAS would be similar to what was available at the pump during the time the Dauntless was first produced.

 

no, but i have ran nitro methanol in a camed up 1967 chevy 327,ohhh it like, turned the inside of the tailpipes grey,and you could really here the cam, reg gas sounded stock

 

i used to run avgas in my rally car years ago.
i makes power with one downfall. it's designed to run at high altitude so it has added chemicals to protect it at altitude, one of the legacies of these chemical's is that it slows the burn front down,, that's why a lot of people comment that there engine runs cooler on avgas. the other disadvantage is the $100000 fine for using avgas in a motor vehicle in Australia.
I'm not sure what pump over there but in my experience is that the high octane 98 fuel's we have in Australia make as much power with similar timing figures as Avgas.
if i was over there i would be looking at a raced type fuel from Sunoco or VP.
but that's just my opinion

 

Avgas has a lower btu rating than gas for cars. The avgas 100 is actually avgas 100/130 witch has the different ratings based on the use, normal aspiration lean(100) versus supercharged rich(130). You have to remember in 1966-1971 the 9:1 compression of the Dauntless motor would have been low compression and designed to run on 91 octane fuel, now days the rating is done by averaging between research and mechanical, they didn't used to do that years ago.
By todays standard the Dauntless would have been designed to run on 87-89 octane fuel.
As Howard said unless you just need the lead or have a Dauntless with 12:1 compression it would be a huge waste of money.

 

this is very interesting info. thanks.