Passenger side knocking on 425 Nailhead

[Skoki]

Hey guys. I am experiencing some knocking coming from the Passenger side of my 425. It seems to only happen under acceleration and only after driving for 10+ minutes. Any ideas? Also I've been using regular unleaded gas. Is this the right one for a 66 electra with a 425 Nailhead? Thanks for the help in advance.

[bob k. mando]

static compression ratios on a 66 Nail blueprint at 10.25:1, so regular unleaded is probably a bit low.

you either need to run premium or fill up some 10gal cans with 100 Low Lead Aviation Gas ( 100 LL AvGas ) from a local airport. if you get real adventurous, you could pull up with an empty 55gal drum in the back of a pickup and fill that.


if you go 100LL, AirNav.com is a great resource for checking fuel prices at FBOs in your area. and you should definitely check around. prices can vary more than a dollar a gallon at strips in a hundred mile radius.

http://airnav.com/fuel/local.html

[Skoki]

Thanks for the heads up. Your the first person that has been able to answer that for me. Do I need to run the tank dry before I switch to Premium or can I just add it to what's already in there and transition from here on in?