I have been getting conflicting reports on what type of gasoline to run through my 64-1/2 mustang. I pick it up this weekend and want to do it right. I am a beginner, so need some good, simple advice.
it should run fine on 87, if it has sat for a looooong time you might want to pick up some lead substitute until you get the heads rebuilt (the old engines need to have their valve seats hardened to handle modern gasoline, if its sat a long time, like decades, this might not have been done). But there should be no problem running 87. If its a 289 hipo, then maybe stick 89 or something in.
run normal gasoline. you wont find leaded anywhere. is the motor original? if it was ever rebuilt in the last 20 years, id hope it would have hardened seats. theres not much else you can do. i run premium gas, 93 around here. or use a lead substitute if you think its really neccessary. these cars were designed to run on leaded 100 octane and up. you wont find that much of anywhere. most people just run regular 87 octane. try it out and if you dont detonate, your good
Run the lowest octane you can get away with without pinging. With a stock cam that's probably 89-93 octane, with 87 you'll have to retard the crap out of the timing to run it, which will lose you considerable HP.
Run the lowest octane you can get away with without pinging. With a stock cam that's probably 89-93 octane, with 87 you'll have to retard the crap out of the timing to run it, which will lose you considerable HP.
Good info, but not completely accurate. Close though. I used to run AvGas in my 427 Stang, but I'd cut it half and half with leaded regular. And it never suffered a meltdown. Biggest drawback to is was the Benzene that made the carbs leak.
Good info, but not completely accurate. Close though. I used to run AvGas in my 427 Stang, but I'd cut it half and half with leaded regular. And it never suffered a meltdown. Biggest drawback to is was the Benzene that made the carbs leak.
Have done the same in mine - 50/50 with no problems in sprint races. The Enduros are run with standard Hi-Test because they are not flat out for 3 hours.
He made a good point as to compression ratio and cam profiles. The 67 Stang coupe I bought a few years ago had a warmed up 302 in it, with 289 heads, cast flat top pistons, .015 deck clearance, and an RV type cam. It wouldn't run on 87 at all, pinged like crazy. It would run on 93, never had the chance to try 89. My 68 Merc's 390 did likewise with the stock cam and 10.5 to 1 compression, wouldn't run on 87 (or even 89), but with the Crane Energizer cam it's got now, is happy with 89. And my 331 stroker, just didn't ping with 87 ( this was when I first fired it up, and had a tank full of 87) the noise it made sounded like a rock crusher. Never heard one do that before, scared me enough to drain the 87 out and replace it with 93. Comp ratio with it is 10.4 to 1, cam is a Ford Racing Z303 roller.