fuel and additive question

bnchief

bnchief

Senior Member
I have a new motor in my model A it has a police head b cam zenith carb power balanced fsi ignition insert rods and bearings hardened seats(exhaust) and valves and adjustable lifters.

That said i can get get mid-grade gasoline 89 octane no ethanol.I know alot of people add marvel mystery oil to their gas how much per gallon? Also gunk makes a lead substitute does this help protect say the intake valves even though the exaust seats are hardened.

What about octane booster not needed or does it help?

I know this question is opinions but i have recieved a lot of help here.
 
The lowest octane today is OK for a Model A.

The fuel additive answers might resemble the 1-5 Star ratings on Amazon.com; just take your pick.
 
What did your rebuilder suggest? Obviously having good gas available will work to your advantage. I personally use one can of Seafoam per tank of gas. Wayne
 
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Since you have non eth 89 available to you use it. Octane boost is not needed and using MMO is your choice. Throw it in every tank or every few tanks or not at all again it's your choice. many like it to help lube the guides, carbon control etc. Your already at an advantage using better fuel
 
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Hi bn,

You hit the nail on the head.

One can always ""witness" less cylinder wear at bottoms of cylinders where ample oil is available ..... far more cylinder wear at tops of cylinders where less top cylinder lubricant is available ....... thus causing a cylinder wear ridge at tops of cylinders.

Plus, engine lubricant not only reduces friction ....... it also helps as being an additional coolant close to the combustion chamber.

In my opinion, vintage 4 cycle engines with a lack of top cylinder lubricant indicates a debatable lower and rear heavy lead problem .... but not in the vintage engine .....
 
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Hello, I'm new to the site, I have an 1950 f1 and a roadster 1923. I have a front crank leak on the f1 that is driving me nuts I had the engine rebuilt 6 months ago the 276, 4 in stoker she run great just that little front seal is a pain. IF you got some ideals let me know Thank you. Jim
 
Jim Kerby said:
Hello, I'm new to the site, I have an 1950 f1 and a roadster 1923. I have a front crank leak on the f1 that is driving me nuts I had the engine rebuilt 6 months ago the 276, 4 in stoker she run great just that little front seal is a pain. IF you got some ideals let me know Thank you. Jim
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Jim,
Go to the top of this page and click on "The Forums". Then click on "Early Flatheads". You will probably get the most help there.

Good luck with your F1!
 
MMO in the fuel is OK.......But I would also like to suggest a ZDDP additive in the oil before any gas additive.....
 
I wonder how Model A's lasted before ZDDP was added to oil in the 50's? Probably needed a rebuild every 5,000 miles or so.
 
captndan said:
Use Rotella T and don't worry about your oil.
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Agree it has plenty of zinc in it,,,,to add they are changing their formulation to T4... i have not seen the zinc levels on this yet.. i heard they are releasing that info after the new year... does anyone know???
 
I am using Mobil delvac same specs as shell rotella for the same reasons. By the way Mitch i got that steering gear back together and everything back in the car hope to finish it and fire it up next weekend.
 
ditto to Dino et al. Evidently zinc removed from oil because of havoc with catalytic convertors. Zinc additives study done by Porche Club sometime ago with recommendations for zinc products re; wear on flat -opposed 4 cyl's. STP had zinc in the red bottles but no longer sold in Cal. (EPA reg's), so any product with Zn may be beneficial.
 
Jim Kerby said:
Hello, I'm new to the site, I have an 1950 f1 and a roadster 1923. I have a front crank leak on the f1 that is driving me nuts I had the engine rebuilt 6 months ago the 276, 4 in stoker she run great just that little front seal is a pain. IF you got some ideals let me know Thank you. Jim
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I have a great idea, have the rebuilder fix his problem. The problem is his not yours. Wayne.
 
bnchief said:
I am using Mobil delvac same specs as shell rotella for the same reasons. By the way Mitch i got that steering gear back together and everything back in the car hope to finish it and fire it up next weekend.
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Nice keep the updates coming
 
The zinc has been gone a long time now; has anyone reported definitive harm done to Model A engines that do not use additives? Seems like I heard many experts say some time ago that only modern, higher performance engines were vulnerable. It would seem that by now problems would be surfacing.....none of my Model A friends have reported any issues due to it.
 
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