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Unleaded Gas

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W

wsm

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Does anyone know whether it's really important to add a lead additive to a 1275 cc Midget engine? (I know hardened valve seats have never been added to this engine). As far as I can tell the prior owner never used a lead additive, and I'm getting mixed advice on the subject.

Thanks, /ubbthreads/images/graemlins/england.gif
 
I don't but I don't drive my little Midgets much
 
I never did the "no lead head" and have been running unleaded for I guess 20 years now. Never a problem, in fact, the oil and plugs stay cleaner longer.
and I drive as much as I can and I don't baby any of my Sprites.
 
Oh, when I drive mine - I DRIVE MINE!
 
So, I guess your guys are saying the heck with it and just clean up the head and grind the valves. New guides as necessary.
 
my 2 cents is you will know whether to use lead by the way it runs. All mine need lead( American & LBC's) The difference in performance and idle is significant. If you've never used it or don't have a problem -dieseling or rough running- there probably isn't a need. If it stutters and you've tried everything to even it out - lack of lead may be the secret.
 
I'm racing on 100 octane unleaded (Sunoco GT). No problems in years, and my cylinder head comes off for other work pretty often.
Many of the "lead substitutes" are not real lead and are mostly for detonation prevention...and most raise octane only slightly.
I'm with spritenut on this. Your engine will stay cleaner (especially the plugs) with unleaded.
 
Occassionally toss in a tank of 93-octane Amoco white gas!
 
I run 87 unleaded in all my cars ..except the 14 to 1 racer. It gets 100. With 8.8 to 1 that is all you need.
Even with the stock heads 1275 units seem to live ok with nolead fuel. I think that they come with some pretty good head and valve material from the factory.
I do however install harden seats, stainless and stellite valves in every head I go through.
Run the unleaded I be it will work fine. Don't waste your money on 93. A stock A-series doesn't have the compression to need 93 or more. In fact your milage may drop a bit with 93.
Another myth is 93 has more detergent...it does not. Just buy good fuel from a company owned station. The fuel you buy from stop and robs is junk, old, surplus fuel with little detergents added.
 
So what are you telling me, just grind valves and new guides or new seats, and valves.

Keep in mind this will not even be a daily driver, I don't supose I will ever get 10K miles on it in my life time.
 
Read the part where I say "I do however install hardened seats, stainless and stellite valves in every head I do" I would run an old unbuilt engine without doing the head on unleaded fuel and no additives. I would not build an engine without the new kinda stuff.
 
Thank you Jolly, appreciate.
 
You do not need a lead additive. You have a '74.
All cars sold in the US since 1971 have to be able to run on unleaded.
 
Thanks all for great replies. The information is very helpful. Mike, I'm especially interested to learn that all cars sold in the US since '71 were prepared for unleaded. This forum provides the best information on my Midget that I have found anywhere.
 
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