Octane help

[Mr. Chevy]

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

[VintageMusclecar]

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

https://static.summitracing.com/global/images/prod/mediumlarge/mef-100032_ml.jpg

https://www.summitracing.com/parts/mef-100032?seid=srese2&cm_mmc=pla-msn-_-shopping-_-srese2-_-race-gas

[bigjake]

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.

[Mr. Chevy]

Thanks Fellas...

Rich

[L89DRMR]

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

[CanCOPO]

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

[TimG]

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.

[Canuck]

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.

[Lee Stewart]

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."

[novadude]

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

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".

[olredalert]

----For several years now I have filled up the old cars that need premium with 103 octane racing fuel at the beginning of the year. Then, as I use them and bleed off some of the 103 I re-fill with 91 octane marine fuel (no ethanol). I have a regular gas station near me that carries marine fuel. That 1st tank is a bit expensive but I hardly ever run thru a tank in a summer and the cars run great. I would hazard a guess that I'm a bit lucky living in a heavy boating area as well as being able to buy 103 at the pump, but Ill take it!.......Bill S

[Mr70]

$6.49 a gal. 110 leaded here at the Gas N go.
Mix it with 92 and... :burnout:

[markinnaples]

Dang. I pay just over $9/gal for VP 110 here.

[Mr. Chevy]

Thanks again for all the advice...

Rich