Lead additive

[Silver R/T]

should I start using lead additive in my 68 with original 906 heads, I do not think theyve got hardened valve seats.

[MoparYoungGun]

Unless you do have hardened valve seats I would. I know in our Buick we were told to do this as more of a precaution than anything. The only problem is it is getting harder to find at local stores, at least in my area it is.

[Nacho-RT74]

here in Venezuela is coming also to the unleaded gas only on gas stations... Goverment says because enviromental protection, but As far I know, uneaded gas needs the catalistic converter to REALLY protecs the enviromantal... Could somebody give me a light about that ?

[Silver R/T]

well Ive had some free time today and Ive researched on net and found this...
http://www.356registry.org/Tech/leadadd.html

supposedly Chrysler heads are bit different so they DO NOT require Lead additive
"Chrysler is an exception - in at least some of their engines they used insert seats of a different material in the cast iron heads."

[Ghoste]

But does that apply to 68 heads or is just ones cast after 71?

[cudaken]

 I have never ran lead in my 68 Runner, 69 Charger or 70 Cuda. All are big block's car as well. Have 80,000 miles on the Cuda's 383 I will add.

                       Cuda Ken

[Chryco Psycho]

I still think having hard seats or using an additive is cheap compared to rebuilding the heads
using unleaded gas helps the evironment by not putting lead into the atmosphere , the cat is another step

[Nacho-RT74]

what's for the catalistic converter then ?

why is used on unleaded gas cars and not on leaded gas ?

[Ghoste]

The lead coats the platinum surfaces inside the converter first rendering them useless and eventually plugging the converter off.

[Nacho-RT74]

Ok, so what's the catalistic converter on unleaded gas cars for ?

[Ghoste]

The converter can only be used with the unleaded cars because the leaded fuel clogs them.  It will work for a short time with leaded fuel but then go for the crapper.  If I remember, the converter is used to reduce nox emissions.

[Afflyer]

  You guys have confused me a little with the talk of valves, heads, etc. with using lead additives.  My '68 440BB has NEVER been rebuilt.  With that said, would it be a good thing for me to add some lead additive to my engine, or just use plain old 93 octane?  If I could find an airport that sold AVGAS (5 gallons at a fill up), I would use that as I used to in Arkanas, but I've yet to find one.

Bradley
Milton, Florida 

[Ghoste]

It's not going to hurt, but it also depends a lot on how you're using the car.  A lot of those old muscle motors will go for a long time on unleaded if they are not being driven hard.  Me personally, I'd try and run some in there once in a while or else pull the heads and get hardened seats.

[Plumcrazy]

I've been running without additive since I last had the heads off 20 years ago.
This winter I'm swapping them for a set a Eddy aluminum heads.  I'm curious what they're going to look like.

[Nacho-RT74]

I think would be cheaper and also better if you already have open chamber heads, get a late 70s truck BB heads and install them. Just to keep safety on valves. also I have known about those heads the intake and exhaust ducts are wider, buit not sure about that... those heads are DIRTY CHEAP.

[Afflyer]

Okay, so you're saying XNAY on the lead additive and just run plain 93 octane?  I'd run 5 gallons of AVGAS if I could find an airport that would sell it to me here.

Bradley 
Milton, Florida

[Ghoste]

There must be a place somewhere.  Your best bet is a smaller type of place with a single paved strip and a whole bunch of little Cessna's.