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Question on lead additive

vanceboy

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To all,

I own a 1969 Charger RT with a 440 magnum engine.

Should I be using a lead additive in my gas?

If so, how often? Every tank?

Which lead additive do you recommend.

Finally, I know this isn't the right forum but I'm so excited,

I just bought a 1969 Plymouth Satellite! At least it's a B body!

Hope to make it my daily driver!

Vance

satellite1 small.jpg
 
Engine rebuilt with hardened valve seats or no? That's what matters.
Unfortunately, I do not know for certain. It was rebuilt with aluminum ProMax heads before I bought it.

Can I assume that since they are aluminum heads that they would have hardened valve seats?

They would have steel inserts, and no one would put in non-hardened inserts, would they?

Vance
 
I’ve been driving the 383 in this since 2004. It’s been my daily everyday since 2014. All I’ve ever put in the tank is 93 unleaded. The engine’s never been apart, and doesn’t burn much of the Mobile 10w-40 I put in it.
IMG_8983.jpeg
 
To all,

I own a 1969 Charger RT with a 440 magnum engine.

Should I be using a lead additive in my gas?

If so, how often? Every tank?

Which lead additive do you recommend.

Finally, I know this isn't the right forum but I'm so excited,

I just bought a 1969 Plymouth Satellite! At least it's a B body!

Hope to make it my daily

To all,

I own a 1969 Charger RT with a 440 magnum engine.

Should I be using a lead additive in my gas?

If so, how often? Every tank?

Which lead additive do you recommend.

Finally, I know this isn't the right forum but I'm so excited,

I just bought a 1969 Plymouth Satellite! At least it's a B body!

Hope to make it my daily driver!

Vance

View attachment 1952085
Nice convertible.
 
I haven't used a lead additive in anything for many years - and haven't had a problem with any of the cars/trucks.
For higher compression or race engines, I mix in some 100LL or VP110 on one street car, and use VP110 race gas in the racecar.
I think most anything from the mid-70s, or rebuilt since then, has hardened seats.
 
Promaxx started in 2012. You have hardened seats. Nice ride!!
 
Hard seats in any aluminum head. So no, you don't need lead additive.
If it's detonating on the available gasoline, you might need an octane booster.
 
Even those made pre 72 ?
Never had a car with aluminum heads pre 72 so idk.
Yep.
Only factory aluminum heads I know of prior to 72 would be the incredibly rare sbc, big block chevy, and Hemi. All of those were high performance versions, and would have needed good seats.
I'm not sure when aftermarket aluminum sbc heads showed up, but I bet they had good seats from day one, too. (Brownfield?)
 
Be careful of octane boosters. When they say "increases x amount of points", some mean point points.
Say it says five points. It doesn't mean a 91 goes to 96. It means it goes to 91.5
 
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When the machinist did my heads, I asked him to install hardened seats. He said "how much are you gonna drive your car?" I said 1000 miles a year maybe. He said "you'll die before you wear out standard seats" I'm not dead yet, but I have put only a couple thousand miles on my car in 13 years, so I guess he was right. As far as octane booster, don't seem to need it. We have 94 octane Chevron up here in Canada ( sometimes known as Soviet Canuckistan to our southern neighbours.)
 
I’ve been using Bell Performance (aka Bell Labs) products in all my engines from truck to weedeater since the early 80s. Read an old article on Don Garlits who swore by them. With the gas engines in the beginning it was Mix-I-Go and now Ethanol Defense. Cleans everything it touches, lubricates, removes water like a mist, improved my mpg and protects against ethanol.
Sorry if sound like an infomercial but damn this stuff is good.

It’s really fun to see the results in a lawn after the initial heavy cleaning has been accomplished. They rev much smoother and cut a lot more grass on the same tank. Also they start easier after a long winter.

Fuel Additives | Diesel Additives | Oil Additives | Bell Performance
Ethanol Defense (16 oz.) - 16 oz. Bottle

Back in the 80s a friend had an old pickup with camper and was going on a long road trip, so I gave him a bottle and told him to have a couple fuel filters on hand since it may clog it until the cleaning was done.
He got back and was so excited his fuel filter plugged up, but he forgot to get some and got stranded. LOL He changed it and over the trip he kept getting better mpg. He was sold on it.
 
I’ve been driving the 383 in this since 2004. It’s been my daily everyday since 2014. All I’ve ever put in the tank is 93 unleaded. The engine’s never been apart, and doesn’t burn much of the Mobile 10w-40 I put in it.
I’ve used Mobile One every 10k in all my cars forever. I had a 97 Neon that went over 300k. I only changed the timing belt once at 200k and the old one looked new.

I don’t drive a lot these days due to a bad low back injury.
 
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