"Does Octane Make Power"? Engine Masters Watch On MotorTrend Network

[Jim L.]

Re: "Does Octane Make Power"? Engine Masters Watch On MotorTrend Network

I watched last evenings episode and wondering about what was not discussed. The FI unit on my 60' runs fine on 110 leaded however, when I had to add some 93 octane with 10% ethanol to get home one day it died at every stoplight and would not idle. Replacing the ethanol blend solved the problem. Is it the leaded fuel that makes the difference with the FI unit?

No, it is the different / lower temperatures at which the components of the 93 octane E10 begin to vaporize which makes the difference.

The reason 110 leaded mitigates the fuel perc issue has nothing to do with the lead content. It has everything to do with the higher vaporization temperatures of the components of the fuel.

With proper modifications, however, your 7320 FI unit can be driven pretty much anywhere on pump gas without having to be concerned about fuel perc issues.

[Tim S.]

Re: "Does Octane Make Power"? Engine Masters Watch On MotorTrend Network

So am I wasting my time getting AV gas when I can get 91 octane without ethanol a buck a gallon cheaper?

It's a good question Joe. As we had talked, I am not convinced we are not getting some ethanol in the fuel where we are. I am seeing far too many gasoline related issues that should not be happening if all is as we are told. The 100LL is held to a high standard due to it's use in aviation.
Tim

[Mark M.]

Re: "Does Octane Make Power"? Engine Masters Watch On MotorTrend Network

I too enjoyed that episode. They used a LS3 engine which is a much more efficient engine than the 327,427 and such engines in our early cars. They used 87 and 91 from local gas station and Sunoco 110 and 116 leaded racing fuel and finished up with E85. The E85 was the only one that had a significant jump in power as it was said to contain more O2. The LS3 only liked 29 degrees of advance in all set ups. They said octane and timing requirements are all based on engine design and build. LS engines breath far better, have much less heat producing friction, use aluminum heads with better cooling passages and fuel systems that are less susceptible to percolation. We can improve any engines mechanical efficiencies but the fuel perc. seems to be a common issue which has frustrated me. I would like to see Engine Masters do the same tests on a 60's vintage performance engine. It is an excellent show.

[Joe M.]

Re: "Does Octane Make Power"? Engine Masters Watch On MotorTrend Network

I too enjoyed that episode. .............
I would like to see Engine Masters do the same tests on a 60's vintage performance engine. It is an excellent show.

As would I There are many thousands of gearheads running old iron who would LOVE to see some testing done on older engines.

[Bob B.]

Re: "Does Octane Make Power"? Engine Masters Watch On MotorTrend Network

Need a good laugh ? Premium pump gas in Calif is now $4.95 , I bought friday, AV GAS at Thermal Airport (local ) is $ 4.50 a gallon-
Just came back from summer in Tennessee premium was $3.25 Thin CA has a bit of a tax issue ?
Leaded race gas VP is a few cents over $10. a gallon, been that way all year.