what is my Octane after sitting 1.5 moths?

[1985GN]

hey guys i have a question when i got into an accident 1 1/2 months ago i had almost a full tank of abnout 96ish octane...the homebrew of 94 and about 2 1/2 gallons of xylene. the car then sat for 1 1/2 months until tongiht when i can take it back out and do some racing. im curious as to waht my octane is now? i heard you lose an octane for every week gas sits?? do i still ahve a good octane rating in there? should i throw another gallon of xylene in just ot be safe? thanks for the help guys i plan on doing some racing tongih and want to be safe.

 

[UNGN]

I don't think you lose much octane. The xylene does a nice job of cleaning the varnish out of your tank so a new fuel filter and FP sock may be needed down the road, but the octane should be real similar to when you parked it.

 

[JayLashua]

what about 17 months??