View Full Version : Lead additives? Octane?


67L48
Jan 15th, 03, 01:11 PM
Since leaded gasoline is no longer available, do any of you use lead additives? Are there any dangers of using/not using lead additives?

Currently, I use premium (I think 91 octane) and a lead additive.

Thanks.

gheatly
Jan 16th, 03, 06:21 AM
If you are using later model heads, you shouldn't need the lead additive.

67L48
Jan 16th, 03, 06:43 AM
My car was built in November 1966. The engine and other components were built in October 1966. Everything is still original -- #s matching.

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K.A. Young

67 SS 350
PowerGlide AT
AC, Deluxe Interior

Daily Driver (http://storm.prohosting.com/~youngka/pics.htm)

BB69
Jan 16th, 03, 07:38 AM
This question depends on how you use your engine. If you do a lot of driving at high RPM, you should have hardened valve seats installed. If you do mostly cruising, and don't put a lot of miles on the engine, a high quality gas with no additives should be fine. Some people have had problems with the additives leaving deposits on the combustion chamber and valves. I had the hard seats installed for about $180, while the engine was apart. Otherwise, I would not have torn the engine apart just for that reason.

Ken

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69 RS, 427, 4-spd
69 Corvette Coupe, 427, 4-spd

DjD
Jan 16th, 03, 07:48 AM
JMO but if the heads have never been off the engine and there is some mileage on it I bet the seats and valves are so coated from all the years of leaded gas that there would be no problem running unleaded without the additive. Now if the heads have been recently reworked and the seats were not replaced keep using the additive.

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...Dennis
"The '69 (http://chevelles.com/showroom/ww.jpg), the '96 (http://www.camaroslimited.com/graphics/memcars/96ss.jpg) our local club (http://camaroslimited.com/)"
and the "daily driver" (http://chevelles.com/showroom/DjD/dsc00016.jpg)

bowtie-70
Jan 16th, 03, 08:08 AM
I always use a lead substitute in mine. I don't put on many miles and it is a stock engine but I feel that it is cheap insurance.

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1970 mostly original
307,TH350
F41

stingr69
Jan 16th, 03, 08:37 AM
I am with Dennis on this one. A fresh valve job could benefit from a couple of tanks of leaded fuel. It is not that big a deal after that unless you do a lot of sustained high RPM driving. If your valve job is fresh, I would run a 50/50 mix of leaded racing fuel with unleaded premium for the first 2 tankfulls or so. After that I would not worry about it. Get some in a gas can from your local speed shop. They can not put it directly into your car.

-Mark.

67L48
Jan 16th, 03, 11:33 AM
It only has 47,000 original miles on it and I add about 500 a year. Mild cruising, though I like to test the 350 on occasion. Sort of sounds like I don't need lead additives.

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K.A. Young

67 SS 350
PowerGlide AT
AC, Deluxe Interior

Daily Driver (http://storm.prohosting.com/~youngka/pics.htm)

[This message has been edited by 67L48 (edited 01-16-2003).]

z28doug
Jan 16th, 03, 03:39 PM
<BLOCKQUOTE>quote:</font><HR>Originally posted by bowtie-70:
I always use a lead substitute in mine. I don't put on many miles and it is a stock engine but I feel that it is cheap insurance.

<HR></BLOCKQUOTE>

I agree with bowtie-70

DjD
Jan 16th, 03, 04:07 PM
I forget the exact year (1976 maybe?) you couldn't get leaded gas at the pumps any longer but there wasn't a mass exidos to the parts store for lead additive. Even though they phased it out over time there were still a lot of cars on the road that ran fine once the leaded nozzle was removed for good.

Anyway I know what it's like worrying about "our babies" and understand wanting to be careful...

67L48
Jan 17th, 03, 09:02 AM
I used leaded gas in my car, from the pump, up through at least 1992.

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K.A. Young

67 SS 350
PowerGlide AT
AC, Deluxe Interior

Daily Driver (http://storm.prohosting.com/~youngka/pics.htm)

DjD
Jan 17th, 03, 09:44 AM
Mr Young - I did a little digging and found that lead was banned from all gasoline after December 31, 1995 in accordance with the Clean Air Act Amendments of 1990. Unleaded came about with the introduction of the catalytic converter sometime in the 70's which is probably where I got 1976 from... I don't know for sure what year the cat was first used...

sunocospecial
Jan 17th, 03, 06:56 PM
Buy racing fuel in 55 gallon drums (Sunoco, VP, Union 76, etc.) if you need leaded fuel. You can mix it with pump fuel as needed.

JohnZ
Jan 22nd, 03, 01:28 PM
The "octane booster additives" all contain a healthy shot of ethyl alcohol, which does three things - 1) Eats the plating off the inside of the float bowls so corrosion can begin, 2) Eats regular rubber and cork gaskets and seals, and 3) Ethyl alcohol is hygroscopic (attracts water), which you don't need in your fuel system. Waste of money.

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JohnZ
CRG
'69 Z28 Fathom Green

DL
Jan 23rd, 03, 08:38 AM
My '67 has a 305ci from a '76-'79 camaro.... I only drive it occasionally about 500-1000 miles a year, low rpm, no racing, just cruising..... At this time I use fuel with a lead-replacement, but I know that the leaded fuel is going to be banned soon here in the Netherlands (Holland). Can I just use the unleaded fuel when there is no leaded available? According to what I've read it is ok....low rpm, no fresh valve jobs etc. Engine is from 76-79 so it should drive ok on unleaded fuel.....
Can someone back this 'theory' up....thnx

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David
I don't suffer from insanity.....I enjoy every minute of it!
'67 Camaro, blue exterior, parchment deluxe interior

Pics http://hobbystage.net/camaro/camaro_crew (http://hobbystage.net/camaro/camaro_crew/)

JohnZ
Jan 24th, 03, 05:32 PM
Just run it - don't worry about unleaded fuel, and you don't need additives. Valve seat recession due to lack of lead in the fuel is essentially an "old wive's tale" unless you're running all day long at 100mph towing a trailer.

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JohnZ
CRG
'69 Z28 Fathom Green