Odd engine behavior after first shutdown of the day

[xb-60]

A basic question, I know, but what octane rating fuel are you using?

Cheers,
Glen

[Sledge]

Thank you, lots of good advice and suggestions. EFI will have to wait a little bit as I blew right through my budget with the new engine and a respray. But I will start looking for the suggested harness.

Other than canned racing gas, I haven't found a source yet for ethanol-free frool. I use the highest octane pump gas available, which is usually 91 octane. I haven't flown an airplane in years so I don't have a friendly source at an airport.

Lubing the advance pivot points never occurred to me, so great suggestion I'll try it today.

Cheers +,

[Skip J.]

Hi Sledge - I have a QF 750 CFM carb on the 393 in my Lone Star Cobra Replica and also on the 383 in my wife's '67 Nova. Started having issues with the engine in the Nova doing what I suspected to be vapor locking on a regular basis. Pulled my hair trying to find solutions and after some research, I found that Quick Fuel made what they call their Quick Cool Carburetor Insulator Kit.

The main insulator plate consists of a poly material sandwiched between two thin sheets of aluminum. The cost was a little less than $100 so I ordered one, installed it on her 383 and we've not had a single issue since and that was four years ago.

Since Holley purchased Quick Fuel, I wondered if they still made the insulator kit. Looked up my four year old part number, found that although the part number had changed Summit Racing does carry it. Hopefully the following link works for you but if not, the part number is 300-4013QFT.

https://www.summitracing.com/int/parts/qft-300-4013qft