I've noticed a few posts by members that have said you can look forward to burnt exhaust valve seats running no-lead gas. My nailhead pings as soon as the timing gets beyond factory specs. This is of coarse asking for detonation, melted pistons and burnt valves at high rpm. I think todays gas is a lower octane rating than what gas used to be and alot of people haven't compensated by adjusting timing accordingly. Some have said running retarded timing will over-heat an engine, having timing to advanced will also overheat and put you on the pre-ignition merry go round! Whats your experience running todays gas in our cars? Ian
Ian, Just make sure your total timing is between 30, and 36*. Most guys seem to do well with 34*. That's what I run. If it detonates, back down to 32, or 30. I use about 3 or 4 gallons of race gas every so often, and use Red Line Lead substitute. You won't have any trouble with valve recession if you use some leaded gas once and awhile. Valve recession is more likely under sustained high load, high RPM operation (Like Racing at the track). Use race gas at the track.
OK, is stead of running retarded.... What I've been doing is adding Tetraethyl Lead with every fill up of the 93 octane swamp water that passes as "gasoline". This brings up the rating to 98-100 real octane. Set my Stage One back to stock timing spec's, no ping. Also, the smell is great. Just like race gas, half the price. Got the stuff from a guy in South Bend, IN at a swap meet here in WI. Runs $13-14 buck a pint, use 1/2 a bottle per fill up. I'll get his info and post it. Jim
Jim, Is this the stuff?? http://www.batterystuff.com/productdisplay.html?id=440&c=6&re=439&f=Octane_Supreme_130_Two_Quarts
Larry, That looks like the same stuff product wise. My guy sells it under "MaxLead" trade name. I'll see him next weekend at Jefferson Swap Meet. I'll see if he can join the forum here. My swap meet price is $13 per quart bottle. $60 seems high, but maybe costs have increased (4x seems a bit much). I came accross the bottle yesterday, I'll grab the 800 number and post it. Jim
Price check I followed the link, looks like $60 will get you 6 quarts, $10/quart + shipping sounds like it is back in the right ballpark. Anyone have any more comments on octane boosters / lead additives? Thanks
I run 12.5:1 (cutlass 455) on $20 worth of 93 octane+$10 worth of 89. It'll ping during acceleration if only run on 89. I just started using some lead substitute that I got from wal-mart for $7. Entire bottle will treat 320 gallons of gas.
Semi O.T Sorry if this is a bit O.T, but I was wondering.... is the 93 octane even worth it? Like they're are several places (Sunco) around here that sell 94 octane, but isn't anything over 89 Octane just have Ethanol added to it, to boost the rating? My point is, wouldn't it be better to buy the lowest rating and spend a few bucks on some octane booster (or lead-subs.) 'stead of pay the extra $$ for the high end crap?
It takes alot of "octane booster" to change the cheap gas to good gas. Those $6 bottles of booster, when you read the small print, raise the octane by .#, not full points. Only buy premium if you need it. 10 Gallons of 87 @ $2.20 a gallon = $22.20 + $6 octane booster = 87.9 octane for $28 10 Gallons of 93 @ $2.40 a gallon = $24 for 93 octane The gas I buy at kwik-trip says it has 10% ethanol mixed in with it (all grades) and it runs really well. I went back to straight gas for a tank and I was sputtering, pinged and basically ran el-crap-o.
Actually I do see your point when you put things down in numbers (granted I don't follow gallons and U.S currency very well) but I get your drift. The only problem I've noticed is my buick doesn't run so hot when I use 93 octane from certain gas station, I gather some stations use use more ethanol in there fuel then others. Personally I'm a fan of 89 Octane with 7% or less ethanol mixed in, of course this is only a daily driver.
If you have the stock timing and compression, you really have no need for higher grade gas, the engine can't use it. The higher the octane, the longer the gas takes to burn in the chamber which is good since it prevents the gas from detonating before it's supposed to (pinging) in a high compression engine/an engine with advanced timing.
well,the prices are crap!! i started using 91 octane mid grade,w/10% ethanol in my 75 le sabre, sems to run better, and mileage is better too
QUIK82REGAL , and mechacode mention using gas with 10% ethanol in it...I remember hearing years ago that ethanol would dry out rubber lines, fuel pumps, etc....has opinion changed on that? Is 10% low enough not to cause problems???
I just run the Premium from Chevron in my Buick. 2.19per gallon. I have no choice but to run the premium in my truck. If I run anything less, it pings really bad. I accidentally put mid grade in it once and it pinged and clattered badly.
FWIW I had a mechanic at the local hotrod shop tell me :rant: DO NOT USE 110 octane gas if your engine is not set up for it as it will cause valve recession. These guys are pretty sharp mechanics so I will have to take their word on it till I'm convinced otherwise. On the other hand he did say a Lead additive every few tanks is a good thing. My new 462 seems to run good on 94 octane. Jay
To the question-A '65 Riv with a 401 or 425 nailhead should do fine with 92-3 octane-especially as many of these after 40 years, now have the thicker composition head gasket=lower compression. You might want to check the advance bushing to see if it's gone-if it is, you'll get a few more degrees of vacuum advance (lighter throttle) than you want-maybe needs stiffer advance springs-yes check the curve. A distributor mochine is ideal-yes check timing-maybe 2-4 advanced. I run mid grade (90-1) gas on '65-6 driver nails with no trouble except at nearly full blasts-
