Already tried the Autolite thing (3 different heat ranges), the Champion thing, the Bosch thing, the retarded timing thing. Actually spent 55 exhaustive hours on a chassis dyno logging and adjusting total advance with a knock sensor and an exhaust gas analyzer. With this vehicle, Splitfires at a .40 gap have the least amount of ping. Champions had the most amount of ping. Ended up at 6 degrees BTC initial and 19 degrees total advance at an early 1500 rpm. Logged 245 hp at the rear wheels @4200 rpm. Also installed a Pertronix electronic ignition module and a 40,000 volt coil. >From: Christopher Hoffman <imperial67@xxxxxxxxxxxxx> >Reply-To: mailing-list@xxxxxxxxxxxxxxxx >To: <mailing-list@xxxxxxxxxxxxxxxx> >Subject: Re: IML: 100 octane in a 58 Imp ???? >Date: Mon, 25 Feb 2002 20:11:14 -0800 > >Robert Dervin/rjdervin@xxxxxxxxxxx wrote: > > I need to run 94 octane in my '58 along with a bottle of booster just to > > keep the ping out. That is with only 6 degrees BTC initial and only 19 > > degrees total advance. Other added advantages to premium fuels are >better > > detergent, more consistancy and smoother running. > >I can run my '67 on 89 without additives and get no pinging (ever since I >switched to Autolite plugs years ago). The car runs cool and can handle the >hills without feeling challenged. The engine has 125,000 miles on it (as >does the rest of the car) and has never had the heads off. It burns no oil, >starts easily even it sits for six to eight weeks, and returns 14 mpg on >the >highway. > >My '78 NYB with 17,000 miles and its original Lean Burn intact runs great >on >89 as well, but I tend to treat it to 91 out of habit (and because I rarely >drive it). I'll let you know how it survives to 20,000 miles. Ask me in >another 10 years! > >IMHO, anything over normal pump premium (which is 91 octane here in CA now) >is unnecessary. I'm sure it would love the treat of 100 octane, but to me >there is no need to worry with ordinary gasoline of a good brand name and a >reasonable octane rating. I also believe Chevron uses the same amount of >Techron in all its octane ratings, so there does not seem to be a detergent >advantage to premium these days, either. > >Go with the Autolite plugs, set the timing 4 degrees retarded from spec, >and >enjoy! > >Chris in LA >67 Crown >78 NYB Salon > > >