Good day all,

I don't know what I'm looking at. I've been trying to get my '66 Toronado running perfectly and, for the most part, it is. I've just been fighting a difficulty when starting it in the morning on hot days. I suspect the choke isn't dialed correctly. Anyway, I've had it out for some decent highway runs recently and I must say that it feels great. Seems to accelerate hard, cruises nicely, no complaints about drive ability at all.

So, just out of curiosity, I popped a few plugs out to have a look to see how it's running. Now, I'm running 91 octane premium fuel with a VP racing octane booster as I only add enough of the stuff to mathematically work out to 2 extra octane points. I wanted to run 93 but it doesn't exist here. Unfortunately, the octane booster seems to color the plugs a shade of orange so it kinda skews the plug condition.

At the same time, I used my fancy little borescope to have a peek at the tops of the pistons. Again, I have no idea what I'm looking at. Am I seeing signs of detonation? Or is it just carbon being burned off? Bear in mind, this car was running pig rich for many years before I straightened out the multitude of carb issues this car had prior to me getting it.

Anyways, any observations would be much appreciated. I'll attach pictures of the plugs and a few pistons. Engine is original to the car, never been opened up/rebuilt.

 

I hate piston pictures from bore scopes. Really almost impossible to get a good view from that close to the camera. Pistons look about like I would expect for an old car.

Is the hard starting issue after it sits for a few days ? If so just get used to it. Seems to be the thing with Ethanol laced fuel in carburetors

The other thing is you might be overdoing it with the octane boost ? Too much octane can be just as bad as not enough. I would be careful trying but I almost bet that engine would run ok on 89 octane pump gas. I did a 66 425 for a customer a couple of years ago. Ill take a look at my records in the morning and see which pistons I put in it. Ill ask him what fuel he is using. His is in a 88 convertible. Pretty sure we put the high compression pistons in it.

 

According to what I see in these 3 pics, they are Hi Compression pistons. Note the "V" notch on the left side of the pic.

How many miles on the plugs ? I tend to agree with BillK on to much Octane Booster.

 

Ok thanks for the advice Bill, much appreciated. The engine has about 81,000 miles on it so I guess it's to be expected that the pistons look like that. Maybe I should have backed off the brightness of the light a bit, might show the pistons a bit clearer. I'll play around a bit with it.

I've figured out the hard starting problem, it's the choke. Even in very hot weather, if the engine is cold it wants a fully closed choke to start. I figured it out this morning when I got my wife to attempt to start the car while I held the choke butterfly closed with my hand. It fired right up so I guess I need to bend the choke rod a bit more so that it's totally shut when starting. For whatever reason, it needs that full choke. I had it adjusted exactly as the CSM suggests but it's just not enough choke on the cold engine. Why? No idea. It's not an issue of sitting and the gasoline evaporating as it will act up like this, reliably, the day after I've used the car all day.

The octane booster I was using is the VP racing stuff that claims "up to" 8 full octane number increases. I cut the dose way back to only get me about 2 extra points so I don't think I'm using too much of the stuff but maybe I'll try backing it off a bit on my next fill up and see what the plugs look like. Apparently the stuff they use in octane booster these days (MMT) is notorious for the orange plug dust.

 

Plugs have about 100 miles on them, roughly. I didn't mix a whole lot of the stuff on my last fill up but maybe I'll back it off a bit on the next one.

I just checked my notes.....using the VP instructions, the dose for + 8 Octane #'s into 10 gal of fuel equals 1qt (946 ml). The dose for + 4 octane #'s into 20 gal of fuel equals 1qt (946 ml). I only added 10 gal of fuel at the time so I used 230 mL for 10 gallons of fuel which, according to the math, works out to a #2 octane increase. 230 mL isn't a lot of the stuff but maybe I'll cut it in half.

 

Unless you sandblast the plugs clean, you have no way of telling what less Octane Booster did.

 

Yeah, good point. Maybe I'll throw a new set of plugs in it after this tank and hold off on the booster for a bit.