I have a 440/6 in my Challenger with Edelbrock aluminum heads. I've been reading some articles on fuel and leaded fuel, I'm far from an expert on fuel or an expert on aluminum heads and valve seats but would using a lead additive such as Gunk help with engine performance and protecting valve seats? Just wanted more information and inputs before I use the product.
Thanks!

Those Eddy heads come with hardened exhaust seats. I wouldn't bother with additives. Frankly I don't see where all this anti-wear stuff comes from. Had a set of 915's that were ran with unleaded gas for 20+ years on its soft iron seats, and wear was what one would expect to find with today's standards. Lead is used in racing fuels because it is a very effective octane booster.

However I, like you, am no expert. More knowledge will chime in I'm sure.

i always thought lead was primarily used as an exhaust valve lubricator and seat protector rather than an octane booster. it may offer some boost, but ?? clarify please, any chemists out there ?

Where'd you get that idea? Apparently you always thought wrongly...

https://en.wikipedia.org/wiki/Tetraethyllead

Evidently you need to do some more research, the chemical, Tetraethyl(SP?P) was added to lubrictate the valves and valve seats to prevent burning the valves and pounding valve seats out, it is not a octane booster The higher you refine gasoline the more octane you will get, but less volume per gallon of crude for the higher octane products

Why is does race gas contain lead? Surely engines built today would have hardened seats. And not require lead.

I have to agree with Cab. Lead was added to supposedly protect the exhaust vales from burning and the valves and seats from excessive wear. With the demise of leaded fuel came the need for hardened seats. However, with that being said, I have run several sets of iron heads for years without significant wear. If I were to build an engine for long term road use, I would use hard seats. To the O.P., don't worry about lead substitutes with your heads, they already have hard seats.

Lead is added for octane and also protects the seats by padding them with deposits. Lead was removed and octane went in the crapper. It is very complicated and expensive to get much more than 100 octane gasoline without lead, that is why ethanol is so great.

No, you are wrong

http://www.environmentalhistory.org/billkovarik/about-bk/research/cabi/ket-tel/

It's other benefits were secondary at the time.

Tetraethyl lead was put into gasoline to increase the octane.
PERIOD>

It was back in time after another energy crisis, like in the 1920s.

You could go back and read about it if you wanted to.

The lubrication of exhaust valve seats was a happy coincidence.

All aluminum heads have hardened valve seat inserts for both exhaust and intake valves.

Really, I don't know where some of you guys get your wrong ideas.

Did any of you guys read this entire paper and links? I didn't read all the links but I did read most of the paper
You guys need to remember or become aware that all early gasoline(pre 1950s) was white gas(Coleman lantern fuel), not the gasoline we know today I started pumping gasoline in a service station in the mid 1950, most American produced gasoilne burning automotive 4 cylinders, 6 cylinders and V8 engines at that time had less than 8.0 to 1 compression ratios The higher octane gasoline fuels(130/145 octane) used and developed in the WW2 era where for low RPM aircarft engines used in combat, most of them where supercharged, turbocharged or both The paper linked above is written either by a engineer or Professor or a perhaps PHD canidate Doctortate thesis as a research paper so it is filled with his opinions and the links to his sources justify his opinions Is his work, his or her opinion, the absolute truth? Maybe, maybe not My degree is not in chemistry Todays engines that run on todays gasoline are designed for today gasoline with no lead additives, do they have Iodine additives in todays fuels as a octane booster? Have any of you used or tried to use Toulene or Toulol or Benzine or MEK or Acetone with Methanol alchlol in race gasoline to go faster? I have
Lots of ways to skin the kitty to get results, not all of them are the only way or the best way
Please do not confuse antiknock chemical results with increased octane ratings

Antiknock IS octane. There are many ways to slow down combustion. Lead was cheap, but has negative side effects to human health and Catalytic Converters and O2 sensors.

Sorry guys I have to disagree. Lead was discovered as an octane booster in the early 1920s by Charles Kettering under the direction of GM as an employee of Delco (which he owned and sold to GM). The sole purpose of his work was to find a cheap and effective octane booster, because those 20 hp engines in the 1910s had 6ish:1 compression. Oil comes out of the ground with an octane of about 60. The lubrication benefits are secondary (they actually had to add another additive to keep the lead from building up/sticking to everything), lead is an incredibly effective octane booster, and also helps keep engines cool as well as lubricate the valve seats.

I did quite a bit of research on the history of this a few years back, it was absolutely put into use as an octane booster. Excerpt below from his Charles Kettering's Wikipedia page and sums it up well.

"Kettering's research in fuel was based on his belief that oil would be in short supply and additives would allow more efficient engines with higher compression. His "high percentage" solution was to mix ethanol with gasoline, while his "low percentage solution" looked for additives that would be added in small quantities to increase what later would be called the octane rating of gasoline.[18] Thomas Midgley, Jr. and Kettering identified tetraethyllead (TEL) in December 1921 as an additive that would eliminate engine knocking at a dilution of one thousand to one.[18] While use of ethanol could not be patented, TEL's use as an additive could. Kettering and Midgley secured its patent and proceeded to promote the use of TEL as an additive instead of other options.[19] Kettering became the first president of the newly founded Ethyl Corporation that started to produce TEL in 1923.[20]"

so, is tetraetheyl a different compound[additive] than tetraethyllead ? or are they one and the same ? was the "original" intent to find an exhaust valve lubricator/seat protector and a "side" benefit turned out to be an octane booster ? was "lead" added to tetraethyl after in search of the original intent ? if one reads everything published on the subject that dates ONLY from the late teens to the late 20's, the matter can be interpreted both ways. wiki is a valuable resource, but sometimes can be edited by someone that may have some facts slightly skewed, not necessarily caught by experts in the topic. just wanting to learn. i was also under the impression GULF "NO-NOX" [i think that was the brand] in the 60's was "clear gas", which was in reality, unleaded. who can clarify this ? if not true, which brand was it ? and where did that info come from ? we are no all "rocket scientists" here, but have a quest for knowledge that puts the "myth busters" to test.

NO! Thats bass ackwards. It was an octane booster that turned out to be a valve seat lubricator/seat protector. Tetraethyl can not exist on its own, it exists in compounds with other elements, lead being one of them. When someone talks about lead in gas, they mean tetraethyl lead. And yes, its just Wikipedia, I did my research elsewhere.

Still not convinced? Try the wiki for TEL...

https://en.wikipedia.org/wiki/Tetraethyllead

Right, I believe everything the nation says. You betcha.

Even that article states it was an octane booster though, I didn't read the entire thing but the history/background is accurate.

Toluene. Can't beat it for 3 bucks/gal.

About time to build me a still and cook up my own octane booster!