I called this guy today who sells lead add. and states that with my 10:1 motor I should run 100 oct. like they did in the 60's and while running that my car will run cooler and I'll be able to retard the timing a few degree's and that'll give me 6-8 more h.p.
Does that sound right ?

except I thought more octane allows you to advance the timing

100 oct. for 10:1 sounds right. For him to say that backing down your timing a few degree' s will add 6-8 hp without knowing what amount of timing your engine likes or where it is at now is him trying to sell you some lead additive. JMO

I was just thinking that myself....he has no idea what cam your car has in it or the current timing....so he can't tell you that taking out a few degrees of timing will add hp.

Take out the word 'retard' and replace with 'advance' and it all makes sense.

I'll call the guy tommorow or fri. and ask him more questions.

If it's Jack Podell I've been using his Tetraethyl lead for some tims. usually at 1-1.5 oz to the gallon of 93 octane. It does allow for a little advance on the timing among other good things.

Here's some lead info I tucked away:

**** At Performance Years: Protek, Tetraethyl lead, 1 quart part #RPZ161 for $12

****Try this stuff for detonation problems.
http://www.kemcooil.com/products.php?cId=4
"I use it in my 65 goat with stock compression (10.75 to 1) Along with 93 octane fuel. 3 pints to 20 gallons works well for me. I'm no chemist or fuel wizard but, all I know, is that it stopped detonation under all driving conditions. It's a bit pricey, but, it's worth it to me because it does work. 2 cases usually gets me through the summer cruising season. Good luck."

**** http://www.maxlead2000.com/

Thats the same stuff I'm using, but Jack sells it in quarts....for more than that. It smells good burning too!

My problem is that it seems to hard enough to get 93 octane here in town and when you're out on the road you need a fix bad man. With this stuff, you load up a couple or more bottles and when you run low on gas, you load up with this red kool aid lookin stuff and load the tank. I've never mised it as strong as the village smitty and compression should be real close to his. I have used up to 2 oz per gallon of 91 octane.

That's what I use, too (Kemcooil), one quart per tank of 93. That mix allows me to run initial timing of 6 BTDC without detonation. To run the full 9 BTDC I still need a mix of Turbo Blue 110 leaded/93 super unleaded at 50/50 ratio, so the octane boosting claims are not quite accurate. It does have a good amount of lead, though, and tailpipe emissions do smell very sweet! I bought a case two years ago and still have a couple of bottles left.

My engine is a factory spec untouched '69 400 YT, no head or piston work done, so compression is painfully high for pump gas.

Back when Marty worked for a GM dealer he'd bring me home cases of GM Anti Valve Recession Additive, which was very high TEL. My 'Cuda loved the stuff.

Performance wise, how does adding lead to 93 octane compare with 100 octane fuel? Does the lead also add octane?

Yes, lead adds octane as well as anti-recession properties.

IMO, Turbo Blue 110 Leaded (hard to find) + 93 Super Unleaded mixed 50/50 gives better antiknock protection and minimal valve recession protection. I can run the car hard when fully hot at 9-11 BTDC and not get more than a ping or two.

I was kind of thinking I'd take a few jerry cans (and the car) to the airport when I'm taking the ol' Cessna out for circuit or two and blend some of the 112 Octane stuff.

I still would have to take some additive for the road trips tho...

We can get 94 at Chevron here, have yet to see how it works as I haven't yet fired the new engine.

In this part of the globe, we have either 95 or 98 octane fuel to choose from, I'm running 95 with lead additive and factory timing (9 btdc), engine is completely stock with exception for a 068 cam. Never had any problems w knocking, however occasionally I'm experience some diesling when shutting engine down after running on the hotter side for a while. Might try the 98 octane and watch if it makes a difference. Or even some E85...

I wish I could buy gas in your little world! Trouble is, by the time I got home, I'd need more.
There is one place that has CAM-2, bu they really look at you funny if you put the nozzle in your car.
Jim. I really can't give you a comparison between the TEH and real racing gas. It's been years since I got any.

my 400HO is all stock, except for 10:1 pistons.
100 octane?!! There's no way I can get that here- we have 91 at the pump, and no other sources that I'm aware of. However, I've had the 10:1 setup for over 20 years, and have had no problems, even with today's 91. There is no audible pinging, even if I stomp on it. Also, I've never had any problem with my valves, despite having stock valve guides and running unleaded for 20 years.

I had the hardened seats installed with the rebuild...I suppose I would only need higher octane if it was pinging or running on ?

I'll have to do a comparo between the 100 I have been running and 93 with lead. I know that 93 without lead pings like crazy at any temp over 150. I also know that 100+ octane has definitely got a kick. My car will break loose the tires without much effort when I hit third gear with my automatic. I learned a costly lesson about ping. On a nice 428 I had the lands broke out of the pistons with just a little pinging.

Jim, my engine says the same thing yours does. Real 100 or knock or retard the timing. Even with the static timing at 6 BTDC (reducing total timing to 30 degrees) all it takes is a good stomp to start the knocking.

My pistons are probably beat to heck as I can't get the fuel I need locally. When Pontiac built this engine with "10.75:1" compression which is actually around 10.25:1, 72cc chambers and tall flatttops, they were not anticipating low octane unleaded, and my car has not changed with the times.

Z_Firebird, your lower compression 10:1 pistons allow you to run lower octane without detonation. Bjorn's lower compression cylinder heads allow him to run regular unleaded with full timing and get better power than my 'bird can with all the timing taken out. I've ridden with Bjorn, so it's not speculation.

I have a set of heads and a block and crank but not enough parts yet to build a street engine. I want to keep my numbers-match dinosaur untouched.

I heard on Car Talk that you can have damaging detonation even if you don't hear pinging... they said that by the time you hear pinging it's under extreme duress...
do you think that's true? I'd hate to damage my #s match engine without knowing it....

Whether you can hear it or not would depend on your exhaust system. Another reason for manifolds!
For me, it's getting to be a routine. Go to Sunoco and get $20 in 110 racing fuel and then go to BP and get $20 in super unleaded. Both stations are within two miles of me so I can't really complain....until it's empty again!!! What ta heck, it's cheap entertainment.

It's a quarter tank each way to the nearest 110 station.

Yes, you can have damaging detonation without actually hearing it, if you are attuned to your engine you will feel it as well. I feel a slight drop in power at quarter throttle or more at a point in the power curve where it should be increasing. That's why I limp my numbers-match engine with backed-off timing until I can come up with a proper engine budget. Pull a spark plug on #1 at TDC and shine a bright LED light in. Use a fiber optic viewer if you have one, otherwise use a mirror or just look for pits on the top of the piston. I have a couple of OHC pistons that look like someone bounced framing nails around on them for a while. With an OHC it's even harder to hear, as the cam tower is on top of the head on top of the block.

Yes it's jack podell.

Fbody69...
Jim, Would you like to play a game?...I'll send you a quart of the TEH for experimental purposes if you wouldn't mind performing some for us.

Yes, definitely! My car is running very consistently so it should be a good study. Lead vs. octane. I can also do a minimum and maximum octane study too. It'll be tough, but I can do it.

I just knew that you could. If that fresh PM isn't from you, I'll PM you.

I receive dmy case of lead add. today
I'll it out tomorrow
He advertises it as only adding 19.5 cent's per gallon of gas.

I called him today about that retard, adv. question but he's out of town until tues.

Doug,
From my experience, by getting the octane up, it does allow you to advance your timing.
I did send Fbody69 two quarts to play with. I believe we all know he will take the challenge seriously & put it to the test to give us something to go on.

That's true, if that is the only variable.

My engine was designed to run on 100 octane with 36 degrees total timing. It runs GREAT on true 100 octane from the pump (not bottled additives). Running on 93 octane (7% reduction) requires me to retard timing by 7%, to 33 degrees total timing, to avoid heavy detonation. I can accomplish this by setting initial timing to 6 degrees BTDC instead of 9 BTDC, so if I happen to come across good fuel I can quickly adjust for it. Unfortunately, as it is a compromise, I don't have all the power that the engine should be able to provide.

Kemcooil Lead Supreme 130, one quart per tank, gives a slight improvement. Not what the label claims, it does not allow me to put the timing back but does allow me to drive a little harder with the retarded timing with no detonation.

In an ideal world, I'd be able to easily change distributor limit bushings or adjust the slot and take the timing out there.

If you run an aftermarket ignition system like an MSD, you can get a timing retard box. They are generally used for NOS or other performance adders. But if you set the retard for say 3 degrees, and you run the retard box on a switch, you can switch between your 33 and 36 total timing to match the fuel you are running.

Yellowbird, I know you don't want to use an aftermarket ignition, I am just illustrating it for others that may. You can set these boxed to only adjust after a certain RPM (whenever total time is engaged due to distributor curve). Initial timing is only a number to get you to your total time.

I'm not certain if this is possible, but ideally, instead of a box to retard the timing, you would want it to advance the timing so you could always set the intial low and have the box advance to the 36. This would help in engine crank especially at hot temps.

My $0.02. And my intentions for my car after I get around to the time and money for a rebuild.

With only half a Qt. added I still had spark knock so I added the rest of the Qt. and the bird seemed to like it and no spark knock.

If our bird's were rated 10:75:1 but really were 10.25:1 like Vikki say's then how is my motor 10:1 when I had the block decked ?

Wouldn't that raise comp. even higher ?

Compression is dependent on head chamber volume, gasket thickness, piston notch/dome, compression height, and deck height/deck clearance.

Doug, I presume you did not reassemble your engine using factory metal shim gaskets...FelPro and other composite gaskets are thicker. Did you replace your pistons? What was the compression height? What volume were the valve reliefs? What did the chambers cc to?

This is just to illustrate that you can't order "10:1 pistons" and get 10:1 actual compression. There are a lot of variables. With your engine, Doug, I have two sets of heads in my garage that would drop your compression to 9:1 or 7.8:1 without any other changes. But if yours does measure out to 10:1, that .25 drop from my compression might be enough for the additive to be effective. Next fillup I will put a bottle and a half in and see if it helps. If not, I'll dump in the rest of the bottle.

Padded numbers, whether for horsepower, torque, or compression, was a marketing gimmick of the day. No one stretches claims any more, do they?

I'm in the first stages of building a lower compression engine. That will fix my fuel issues.

You folks are First Class. For those who may not receive High Performance Pontiac, there is an article in a couple of recent issues that get deeply into detonation. I haven't ingested it yet,
but it looks like a really good tech article that deals with the actual reason we are so very deep in this discussion.
Is there really anyone on this forum that doesn't receive HPP?

I was filling another vehicle at a local station yesterday and noticed that the pump has a separate hose for 110 octane leaded racing gasoline. The notice on it says not for street use and mentions a Fed law. I wonder if they will come running out if I pull up with my '68?

I have not seen lead here for 20+ years here.

I'm not a subscriber. My limited budget goes into the car and into the house and the website, not into magazine subscriptions, though I am an avid reader. I do read the articles that are available online.

I fill mine with Turbo Blue 110 leaded whenever I pass a pump. 50/50 with super unleaded.

http://www.turboblue.com/typical.asp

Citgo also has a 110 leaded racing fuel.

http://www.cruisintigersgto.com/for_members_fuel_finder.htm

Jim,
It will depend on a couple of things, primarily who is operating the cash drawer. I've been chewed on at least once for filling the car at the Cam-2 pump. I would tell them I wasn't aware and they gave me a warning as I paid them. It has been some time.
By rights it is supposed to be put in a gas container to keep them legal.

I just emailed my Turbo Blue distributor and they emailed back a list of local stations stocking Turbo Blue 110 leaded. You can do the same in your area. http://www.turboblue.com/master.asp

There is also a street legal lead free high octane Turbo Blue. I haven't tried it.

I was just shocked to see lead. I checked the Turbo Blue link and there isn't any within an hour of me. Although, when in a hurry, I will sometimes stop at a Citgo, I try to avoid them for personal reasons but that might be where I will buy it. The pump I saw had the pay at the pump so maybe I can fill and go.

Jim, you have something against Venezelian oil?