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Has anyone had any luck with an octane booster? I don't want to throw away money on crap that does does not work. This is in lieu of actually running 110 race fuel which I know will cure the pinging issue in the motor.

I'm having issues with running Sunoco or Marathon 93 pump gas in my 67 Impala 327 motor. The motor is a bone stock 275 horse. The compression is 10:01. I have done everything I could to get it to stop pinging with running pump gas: retarded timing back, carbon cleaning, new ignition parts and the exhaust is flowing good motor is breathing.

Any help would be appreciated....

Thanks...

Rich

I haven't used this myself (yet!), but it has very good reviews, is readily available and it's affordable:

https://static.summitracing.com/glob...-100032_ml.jpg

https://www.summitracing.com/parts/m...se2-_-race-gas

Make Your Own Octane Boost

How to make your own octane booster (this is the basic formula of one of the popular octane booster products). To make eight 16 oz. bottles (128 oz = 1 gal):

100 oz of toulene for octane boost

25 oz mineral spirits (cleaning agent)

3 oz of transmission fluid (lubricating agent)

This product is advertised as "octane booster with cleaning agent and lubricating agent!" Diesel fuel or kerosene can be substituted for mineral spirits and light turbine oil can be substituted for transmission fluid. Color can be added with petroleum dyes.

Thanks Fellas...

Rich

Hi,

I had a 1969 Z-28 which pinged no matter what I did until I replaced the distributor advance weight springs with ones that offered more resistance.

One of those little things that can sometimes be overlooked.

Dave

I buy tetraethyl lead from Wild Bills Corvette. It's called Octane Supreme. I have had good results

I've had good results with the Podel and Wild Bill lead additive, but only in 11 to 1 small blocks. High performance big blocks (L78, L71, and L72) only respond to race gas or aviation fuel. All my old cars now run on 100% aviation fuel since we can't get non-ethanol fuel in Central Texas. I keep all of my tanks full of aviation fuel and no pinging and no hard starting any more.

Get Aviation fuel, its not hard to get, all small airports and flying clubs have it. I just bought 10 gallons and it was only 10% more than the best pump gas around here.

Quote:

Originally Posted by Canuck (Post 1361797)

Get Aviation fuel, its not hard to get, all small airports and flying clubs have it. I just bought 10 gallons and it was only 10% more than the best pump gas around here.

"AvGas LL100 stands for "Low Lead 100 Octane". TEL (Tetra-ethyl-lead) is added to raise the octane. When used in a motor vehicle this fuel will leave a lot of lead deposits in the motor. 100LL has a high lead content (0.5 grams per litre), even higher than leaded race fuels. The deposits left when TEL (lead) is burned are corrosive and damaging to valves, valve guides, valve seats and cylinder heads."

Quote:

Originally Posted by Mr. Chevy (Post 1361690)

Unless the decks have been cut, etc. a factory 275 hp 327 actually calculates to something less than the advertised 10:1. Probably more like 9.2:1 to 9.6:1

You say you've tried retarded timing - are you talking initial, or have you actually considered the whole curve? A vacuum advance with no limiter will pull in a LOT of timing. Same goes for centrifugal. It would also be a good idea to check out a/f ratio with a wideband sensor. It's pretty easy to make a Q-jet deliver the required mixture, if you know where you need to go with it.

My opinion (based on experience with 9.3:1-9.8:1 CR 327 & 350ci Chevy engines with mild cam timing) is that a well tuned 275 hp 327 should run OK on 93 octane if everything else is "right".