I have been hearing different stories about whether I have to add lead substitute to my gas. I have been running 89 octane lead free and adding lead substitute. I have had people tell me I can just run non-oxygenated lead free gas and not to add the lead. Is this true or will I wreck my stock 330. Another story was to just add marvel mystery oil or just like 10-30 to the gas and everything will be good. So the question is do I need to add the lead or not?

 

You will hear plenty of stories here to.

The actual experience of most people here, though, is that there is no need for a lead substitute unless you are engaged in very high-load applications, like towing uphill or drag racing. Most of these engines, if opened up at 100,000 miles have NO valve recession, even if run on unleaded (and remember, Amoco was unleaded throughout the sixties and seventies - it was their gimmick).

The 89 octane part is another story, though.

You'll destroy your engine for sure, unless you have the timing so retarded that you kill both the performance and the gas mileage.

You need to use adequate octane for the heat and flow characteristics of the iron heads and the combustion chamber shape, cam design, and compression ratio.

I would strongly advise against anything less than 93 AKI octane, and if you've got some carbon deposits, you may need to go higher than that.

- Eric

 

Welcome to the site, we do like pictures. In my old 330 I ran the 89 throughout the cooler months and switched to 93 in the heat of summer. There is only 1 additive that uses real lead on the market and Octane plus. As Eric mentioned most of us have been running with no additives for years and years with no adverse issues. There are some who swear by one or another.

MMR is a good additive on a quarterly or semi annual basis for fuel and/or oil. It will clean things up.

 

X2 on it will be fine without the lead AND 89 octane is too low, use 93.

 

I have found that if you put low mileage thru the year should be no problem,
But if you do lots of miles per year and extensive driving then you will see wear.
So in short 5000 or so a year no big deal but 100,000 a year then yes, eventual problems.

Gene

 

I can't help much more than the above salient points, but you reminded me that my first real car was a 12 yr old '64 Cutlass.... not sure what the final drive ratio was, but it said "Cutlass" in one place and "F85" in another. Had a power bucket seat. ULTRA high compression 330 4-bbl. Jetaway that shifted to 2nd at 60 mph. WHAT A BLAST TO DRIVE. Hideaway ashtray. Ign could be left in just "OFF" [not LOCKED].... I should never have gotten rid of it.

Thanks for that memory.