Replace the lead in petrol ? Page 1 / 2

neville48, Mar 5, 9:05am
There must be an additive of some sort to put either lead or an equivalent of lead back into petrol for use in classic thumpers.Any suggestions !


NZTools, Mar 5, 9:10am
Why do you need to!
I've had many old V8's since lead was removed, and never had any problems with the dreaded valve seat recession etc.

mm12345, Mar 5, 9:16am
I think Valvemaster is still sold!
That product was developed by Associated Octel (as it was called at the time) - the major maker of TEL.Unlike anything else on the market, it was actually tested on new engines run to destruction, alongside the same engines running leaded fuel.Everything else sold was basically snake oil.
It is still not as effective as TEL at reducing valve seat recession.
Otherwise, you could get some avgas.

franc123, Mar 5, 9:19am
And even if you do have issues with VSR, get the head (s) off and get the seats changed and perhaps get the guides K lined and no more problem, a lot of older stuff with their lower comp ratios is more than happy on 91 in my experience, HP engines are different of course.Lead is ghastly crap that should never have been added to petrol in the first place, its not good for engines, exhaust systems OR the environment.

patiki1, Mar 5, 9:21am
Nulon sell a Lead Substitute,but like nztools i dont use any in my v8.
I removed the heads last year and they were fine.

pebbles61, Mar 5, 9:23am
You can get lead substitute from places like Supercheap Auto & Repco. My mechanic stocks some too, as he deals with classic cars only.

neville48, Mar 5, 9:36am
Our petrol is crap right across the range. It is never the same from tankful to tankful and has been stripped when we get it. I have hardened valve seats but even 98 does not do the deed. I have to run 6 degrees advance,in the states it ran 15 degrees advance no problem. you dont see airplanes running unleaded do you ! wonder why.cause they would be falling out of the sky.Our petrol is crap, all I want is to be able to modify it to hold an octane rating steadily.

bigfatmat1, Mar 5, 10:11am
you dont want lead there is a direct link between gm's introduction of lead into petrol and violent crime.

franc123, Mar 5, 10:21am
Still too many unanswered questions, lead isn't going to solve your problem but an octane booster might, unless theres another issue with the engine. What fuel were you using in USA and under what conditions, climate, altitude etc, is it stock or modified, if stock what is the makers fuel grade and timing recommendations for it, if its been mucked with, whats been done to it! Just saying NZ fuel is crap doesn't cut it.

desmodave, Mar 5, 5:55pm

sr2, Mar 5, 7:16pm
I have to agree with franc123; it's been a big learning curve for those of us that race with the phasing out of leaded fuels. After a lot of testing on both engine dyno'sand in endurance racing the consensus of opinion is that BP98 is delivering the goods in a very consistent fashion. The experience I have had with running it in a variety of race engines (Ra-Spec C Subby, 2.4L 4G63, GT3, 383 Chev and a twin turbo 135i) confirms this belief.

lugee, Mar 5, 8:37pm
Brings back memories years ago of those trays of orange syringes at the station counters.

sr2, Mar 5, 9:29pm
LOL, the possibility of valve recession in Holden red motors was taken very seriously in those days!

rsr72, Mar 5, 9:31pm
#12- That evil stuff that promptly melted the all foam anti-surge in the tank of my classic performance car, gumming up the fuel injection pump completely, filters and complete fuel lines with a brown sticky mess like treacle. Was a major job to strip and rebuild everything, and then ran the car from then on perfectly well without ever bothering to use any artificial lead replacement.

steptoe72, Mar 5, 10:05pm
Doesnt Avgas still have lead in it !.

timmo1, Mar 5, 11:02pm
I was a teenager working in a petrol station back then.I have to admit I got a bit excited every time someone needed a 'shot' so I could shoot one of those little syringes haha

shaun16, Mar 5, 11:02pm
theres still some sitting at my local caltex. not sure if its old stock or people still use it

rsr72, Mar 5, 11:46pm
Yes it does.

phillip.weston, Mar 6, 1:06am
Lead in the fuel is not what increases the octane rating or makes the fuel necessarily better.

elect70, Mar 6, 1:23am
^^ I always thought wasto preventpinkingieupping the octanebyputting TEL in the petrol !

the_chooky, Mar 6, 4:48am
Go see your local aeroclub. they'll sell you a couple of 20's of AVgas you can mix with the fuel your running.

neville48, Mar 6, 7:36am
Yes it does, and why do you think that is aye ! you dont see planes falling out of the sky do you, why have they not developed a lead free avgas! speaks for itself methinks, I continue with my quest.

neville48, Mar 6, 7:36am
Oh yes it does !

gsimpson, Mar 6, 12:53pm
Wasn't the USA one of the first countries to introduce unleaded! After a couple of generations with no lead one would expect the violence to taper off then.

pfemstn, Mar 6, 6:32pm
redline make a good sustitute avalable from BNT. ive seen valve recession on early Ford motors specially those that rev, 302 Ford, Holden, and valiant all prone however that was a few years ago and the fuel may have improved a bit! but best to play safe

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