Lead Substitute

there are many different fuel additives, each does its' own thing... you mention lead and cleaner... what are you trying to do ?

 

jeez, i would call it "overhaul" the carbs?

You are honestly trying to avoid carb overhaul with: "mechanic in a can?"

AGAIN,
LEAD is an ANTI detonant. PERIOD
it is NOT a solvent,
it is NOT a source of BTUs(energy for the burn),
it is solely designed as a fuel additive to deter the inherent "pinging: which is a common design flaw in this era of Ferraris(note all of the shrouded plug zones, the high thirties degrees of ignition advance, the lack of effective oil control internally in the valve guides....early 911s were even worse...)

If you have seat/needle valve problems-pay to fix it, or buy the parts...if you have a 40 yr old car which has suffered from "maintenance" like this...you are here by advised to open the gas cap and go all the way to the intake valves...the probable cause is sludge deposits breaking off somewhere upstream and clogging these valvesand their seats.

I you think the paper fuel filters are going to eliminate this you are deceived...the deposits will form AFTER a filter insitu as a car sits...and the original GASOLINE decays and drys out...
the alchohol used today as a fuel is not really a "strong enough" solvent to render these deposits back into sol, however, they will be a trasport mecchanism...

Lastly, lead concentrations, as will be chimed in by others, used as a lubricant...
had ceased years prior to the manufacture of this engine(209)...another urban myth dispelled...

 

Ditto.

 

additives are preventative measures and NOT designed to clear fouling beyond initial traces, as has been already mentioned, have the carbs physically cleaned/rebuilt, then depending on your useage consider using some appropriate additives to assist in maintaining the quality of your fuel to prevent your situation from recurring

 

I add this at each fill-up and get the feel and impression that with it the valves seal better--like when you come off the throttle there is more back pressure.

Any thoughts?

john
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I think you just need to bring the car to Francois Sicard to have it properly sorted out.

 

Yes, I've been using Redline in my Daytona since engine rebuild 5 years ago. I run half the quantity they recommend, as I found I was getting too much phosphorous buildup on the back of the valves (using a boroscope to check).

Zero wear on valve seats, so it's doing its job.

I also rebuilt my carbs with viton tipped needle & seats, plus of course renewed all fuel hoses from tank to carbs, the latter as much a safety issue as anything else.

I find that modern fuel (we have 98 octane here) leaves a gummy residue when it evaporates, which means frequent cleaning of idle jets is required but otherwise no issues.

 

Thanks Ian, maybe I should reduce the dosage too. What does phosphorous buildup look like? Thanks.

john

 

a red tinged deposit on the back of the inlet valves. You put a boroscope with a 90 degree mirror down the spark plug hole and look at the open valves. It's a subjective thing, you need some there to do the job of preventing valve seat wear, but too much buildup can interrupt the sealing when the valve is closed, plus it can't be good for the gas flow.

I was surprised by the layer of red crud on my valves, next time I looked after a year or so on half dose it was much reduced.

 

Thanks Ian, I do not have a scope, but I do take out my plugs about twice a year for cleaning and sometime I notice a reddish (rust colored) film on the porcelain. Maybe it's time to back off on the use of the Lead Substitute then.

john