Lead gas additive

[RJRENTON]

If you have easy access to 100ll avgas, use that as above. Otherwise, for simplicity sake when taking the care anywhere, I'd have a valve job done w hardened exhaust seats. Really not that expensive and never have to worry about it afterwards.

If you mean installing hardened exhaust valve inserts, it depends on several factors. How much use the engine is going to receive and in what service....racing or just driving; how are the inserts to be installed; what type of inserts will be installed; what type of exhaust valves will be used with the inserts; are the exhaust valves sodium cooled; are valve rotators used, is the engine due for a refreshing and the heads are coming off anyway.
There are literally thousands of gallons of octane booster sold annually because of "its easier to use" or I can't find av gas or "my buddy swears by it" rule. B4 committing to use a booster, research the product. The quantity of booster needed to raise the octane percentage by a significant amount is much larger than expexted.....one can, typically 12-16 ounces, raises the octane rating by 0.5 point. Basically, one can per 10-15 gallons of 93 octane pump gas, will do almost nothing to increase the overall octane. Plus it introduces the manganese salts which will cause premature spark plug fouling......use it at your own descreshion.....your car, your $$$$. Just my opinion of course.
BOB RENTON

 

[33 IMP]

When I still worked in a refinery and had access to the lab, we tested this stuff (with proper lab equipment and in a Waukesha knock engine). While it wasn't exactly "snake oil", the advertising was rather dubious at best as to the claimed results. Analysis found the product to be premium hydrocarbon containing 2 grams per gallon of lead. So, they were selling you a 32 oz. container of 100LL Av gas at 1000+% mark up. Mixed with gasoline at the recommended ratios did not produce the claimed results, however their advertising did not specify which decimal point or exponent of an "octane point" they are actually referring to.

Exactly. They say it will raise the octane rating "five points". What they MEAN, is point five. The customer thinks he's changing his 91 to 96, he's really changing it to 91.5 .

 

[PlymCrazy]

As I consider my options, the additives seem easy enough to locate and get my hands on if choosing to go that route.

But the 100LL av2? Where do you guys buy yours?

 

[mrhemi]

As I consider my options, the additives seem easy enough to locate and get my hands on if choosing to go that route.

But the 100LL av2? Where do you guys buy yours?

Any small airport. Larger centers might not grant you ramp access. If they won't sell it to you for your car, tell them its for your air boat!

 

[PlymCrazy]

Any small airport. Larger centers might not grant you ramp access. If they won't sell it to you for your car, tell them its for your air boat!

 

[PlymCrazy]

Thank you all for the info. I have a 1/2 tank left to decide what I’m going to do. That’s if the sender is accurate of course lol. Once again this place has proven amazing and just an abundance of practical knowledge!

 

[33 IMP]

Any small airport. Larger centers might not grant you ramp access. If they won't sell it to you for your car, tell them its for your air boat!

Tiny airport is where i get mine.

 

[Don Frelier]

I don't think you need to use any additive.
Just run it with ethanol free. The iron is 67 years old and has been heat cycled.
You can run it 30,000 miles and probably hand lap the valves. Yes they might recede some but I would just run it as is.

 

[dadsbee]

Any small airport. Larger centers might not grant you ramp access. If they won't sell it to you for your car, tell them its for your air boat!

I just call for delivery! Next time the new driver will listen to me when I say "don't back onto the grass"!

 

[diesel_lv]

If you mean installing hardened exhaust valve inserts, it depends on several factors. How much use the engine is going to receive and in what service....racing or just driving; how are the inserts to be installed; what type of inserts will be installed; what type of exhaust valves will be used with the inserts; are the exhaust valves sodium cooled; are valve rotators used, is the engine due for a refreshing and the heads are coming off anyway.
There are literally thousands of gallons of octane booster sold annually because of "its easier to use" or I can't find av gas or "my buddy swears by it" rule. B4 committing to use a booster, research the product. The quantity of booster needed to raise the octane percentage by a significant amount is much larger than expexted.....one can, typically 12-16 ounces, raises the octane rating by 0.5 point. Basically, one can per 10-15 gallons of 93 octane pump gas, will do almost nothing to increase the overall octane. Plus it introduces the manganese salts which will cause premature spark plug fouling......use it at your own descreshion.....your car, your $$$$. Just my opinion of course.
BOB RENTON

I know, I know....... I love the copy paste "IMO" above too.

 

[PlymCrazy]

I don't think you need to use any additive.
Just run it with ethanol free. The iron is 67 years old and has been heat cycled.
You can run it 30,000 miles and probably hand lap the valves. Yes they might recede some but I would just run it as is.

Hand lap?

 

[RJRENTON]

Hand lap?

Most (but not all) valve seat angles sre 1° difference between seat and valve head contact, with the seat having the smallest dimension.....like 45° seat angle and a 46° valve face angle. Sort of hard to see the one degree difference (or impossible) by hand lapping (with the good old Clover valve grinding compound a rubber suction cup and a brace as a turning tool).....its done with a piloted stone with the proper angle and an arbor using the valve guide to maintain concentrictity and a motor driven machine......but....it depends on the circumstances.......and the individual......
BOB RENTON



)

 

[PlymCrazy]

Most (but not all) valve seat angles sre 1° difference between seat and valve head contact, with the seat having the smallest dimension.....like 45° seat angle and a 46° valve face angle. Sort of hard to see the one degree difference (or impossible) by hand lapping (with the good old Clover valve grinding compound a rubber suction cup and a brace as a turning tool).....its done with a piloted stone with the proper angle and an arbor using the valve guide to maintain concentrictity and a motor driven machine......but....it depends on the circumstances.......and the individual......
BOB RENTON



)

First I’ve ever heard of it. Thanks for the education sir.

 

[diesel_lv]

First I’ve ever heard of it. Thanks for the education sir.

Back in the 70's-80's in high school auto shop, we hand lapped valves. As said, lapping compound and a long stick that was thick in the middle w a rubber suction cup end. Would spin the stick like a stick when trying to start a fire.

 

[PlymCrazy]

Back in the 70's-80's in high school auto shop, we hand lapped valves. As said, lapping compound and a long stick that was thick in the middle w a rubber suction cup end. Would spin the stick like a stick when trying to start a fire.

This lapping process conditioned both the valve and seat at the same time?

Dad did auto body when I was a kid. Sounds like you’re “rubbing out” the valve and seat. And the lapping compound is sort of the “rubbing compound” here…lol

 

[Don Frelier]

I did these in 1995 and took them off last year.
It always ran really well.

 

[XS22J8R]

There has been work going on for at least the last 25 years to get lead out of aviation fuel.
Recently a lead free gasoline was approved for all piston aircraft engines. The FAA was under a lot of pressure to get this done and the EPA is ratcheting up the heat.
The First Unleaded Aviation Fuel Has Been Finally Approved by the FAA
It won’t happen overnight, but I’d expect within the next couple years 100LL will be disappearing from airports, so those of you using it will need a plan “B”.

 

[Photon440]

Back in the 70's-80's in high school auto shop, we hand lapped valves. As said, lapping compound and a long stick that was thick in the middle w a rubber suction cup end. Would spin the stick like a stick when trying to start a fire.

I have the can with both coarse and fine lapping compound, just turn it over and open the other lid.

 

[gtxrt]

This is the good stuff for octane boosting with real ltetraethyl lead. But very expensive, ver hazardous and not considered street legal.
View attachment 1365820

I still have some of this but with careful tuning and adjusting of advance curves I’ve pretty much tamed my cars needs for more octane and just run 93 ethanol or 91 non-ethanol with no issues. I don’t really consider lead to be an issue on a car that’s not getting 15,000 miles a
year put on it and not towing a load or lugging the car a lot. And there’s less fouling of plugs and combustion chambers to worry about.

edit: I see some are still seeing issues of exhaust valve recession. I don’t put enough miles a year on my cars to worry about that. But maybe some still do.

used it for years they claim full points. any ways i use 8 oz per 10 gallons of gas. with out it i get a slight ping once in a while. does feel more powerful with it.

 

[PlymCrazy]

Next time the new driver will listen to me when I say "don't back onto the grass"!

With some folks these days, don't count on it lol