old gas

Cuddles · PETERBOROUGH, ONT

old gas

Ground Pounder · Senior Member

Cuddles wrote:
My brother-in-law tells me that because my engine is from 1966 when gas was leaded, I may now have to put in an additive every time I gas up. Please tell me, is he right?

He is correct.

dualquadpete · BLACKSTOCK, ONT

I've been doing this for yrs. but I only put the lead additive in about every 3rd. tank [ unless doing a long haul on hwy] but Octane booster goes in every tank, due to compression ratio. Lead additive helps the valves from not "hammering themselves into the seats" on long runs at speed, may not need it if just driving in town??? I also use ZINC additive in the engine oil [LUCAS] as modern day oils don't have it anymore!!!!!

Cuddles · PETERBOROUGH, ONT

Thank you ground pounder & dualquadpete. I guess I'll look in my local Canadian Tire for those additives?

Cuddles · PETERBOROUGH, ONT

Thank you again. I took your advice and bought the additives.

Livetodrive · MARKHAM, ONT

All,

I've never had too much luck with any additives you buy off the shelf in Canada. If the additive actually has the stuff you need like lead, they can't sell it to the public. Most of the "octane boosters" are just cleaners for the upper cylinder to eliminate carbon hot spots. The only exception I've seen is Racegas, the really expensive mix. This guy does a reasonable job of explaining the science:

www.pumptalk.ca/2011/08/octane-boosters-and-high-octane-gasoline.html

DJD · SCARBOROUGH, ONT

you could buy all the "lead' additive you want but the real fix is to take the heads to the machine shop for a new set of hardened valve seats and a new valve job

upgrade the seats or waste the money buying the additive -- same money but only one way gets a return on the investment

eventually you're going to end up paying the same amount buying additive .. and then you'll go past that amount buying additive ..

I would also window shop the aftermarket heads - look for something simular to what you really need and then you have some revelliant cost info on the brain when you go to the machine shop for a price too

in many cases these days it actually makes more sence to buy new complete heads vs fixing the primitive old junk

(I use "junk" in the kindest sence )

Ground Pounder · Senior Member

DJD wrote:
you could buy all the "lead' additive you want but the real fix is to take the heads to the machine shop for a new set of hardened valve seats and a new valve job

upgrade the seats or waste the money buying the additive -- same money but only one way gets a return on the investment

eventually you're going to end up paying the same amount buying additive .. and then you'll go past that amount buying additive ..

I would also window shop the aftermarket heads - look for something simular to what you really need and then you have some revelliant cost info on the brain when you go to the machine shop for a price too

in many cases these days it actually makes more sence to buy new complete heads vs fixing the primitive old junk

(I use "junk" in the kindest sence )

Yeah...However just drive the dam thing chances are by the time it states to act up or tick you will have built another mill or saved enough for upgrades.

DjD check your p/m

Livetodrive · MARKHAM, ONT

Ouch! This is exactly what the wife said about me.......

in many cases these days it actually makes more sense to buy new vs fixing the primitive old junk

fraso · FORT ERIE, ONT

I gave up using lead substitute additive in my gas tank about 20,000 miles ago. My compression is as good now as it was then and, for the amount it will cost for non-guaranteed protection, you can save that money and put it towards hardened valve seats in the future.

I believe this is the product that was recommended earlier:
http://www.canadiantire.ca/en/pdp/certified-lead-substitute-0388006p.html

It costs $8.49 and treats 80 litres. If your car gets 20 mpg and you drive 2800 miles per year, you will consume 640 litres of gasoline and 8 bottles of lead substitute. The lead substitute will cost you $67.92/year so I also think you're better off putting the cost of the lead substitute towards a better valve job or a better set of heads.

I think it's pointless to treat every 3 tanks of gas. The lead substitute deposit on the valve seat wears away so it needs to be continuously replenished.

As for zinc being absent of modern engine oils, this is completely false. Modern Starburst oils are required to have 600-800 ppm of phosphorus (the antiwear component of ZDDP) and this is adequate for OEM-style flat-tappet valve trains (see Engine Oil Myths - GM TechLink). 1200 ppm of phosphorus provides more anti-wear protection and this is found in Heavy Duty Engine Oils at a reasonable cost.

See Engine Wear.

Cuddles · PETERBOROUGH, ONT

Geez, thank you one and all ! So much information. This is certainly a source for friendly and knowledgeable responses. And I apologize for not checking my responses sooner. I have been a little to devoted to working on my ride for the past three months, almost every day for at least 5 hours a day. I'll try to check my mail more often and work a little less on my ride.

Pete Moss · GTA

I personally wouldn't spend the money on additives or getting hardened seats installed (assuming you're not towing heavy loads over long distances or road-racing/drag racing your car or driving it daily to the tune of 30,000 miles per year). I'm guessing the reality of the situation is that this car won't really see a lot of miles yearly AND valve seats don't sink overnight (assuming the seats are in good shape at the present time).

I am not Ford-familiar but there may be/is probably a factory Ford head from an unleaded gas era 302 (I believe I read you have a 289) that will bolt on, giving you factory hardened seats (if the time comes).

If this was a Boss 429 or SOHC 427, I'd do things differently but for a "regular" 289 (no offense intended) I would not worry about it.

On the other hand, if it doesn't see too many miles each year, the added expense of some sort of additive shouldn't really add up to too much so, if it's going to make you feel better, buy it and pour it in :)