Initial Timing w/ today's gas

[miller]

Just going to toss this out, since I've been out for awhile.

Is 10-12* btdc good to go, for the first firing off? 440 w/ 10.1-1 compression, cam lift under .5.
I've been wanting to ask, because of the crummy gas, these days, so...
Seems alot of the guys are putting more in.

 

[moparnation74]

The problem is today's gas.....I wish I had an answer for you. When I add gas to mine I am like the mad scientist putting additives in it.....The crap evaporates so fast it is not even funny....

I have hardened seats so I run a mix of race fuel and pump high octane. Fortunately, here in Texas the race fuel has lead in it and helps to stabilize the fuel and add octane. Aviation fuel is the best but we can no longer purchase it here as a consumer.

My current engine is at the builder now and has been dynoed and has been run several hours every other day for a week. I do recall he put a little more initial timing to it but do not recall that number. I will say if you have a good tuning shop near by it is worth to dyno test and tune your car.....

 

[miller]

Really appreciate that, moparnation74!

Sounds like a real crap shoot. At least for my initial start, and the blasted first 20 minutes. Guess I'll be safe at 12*, with my compression, and go from there.

The crap evaporates so fast it is not even funny....

That's the part, that's bothering...I'll deal with it, when I get there.

 

[Bill Monk]

12 should be a safe place to start, around 18 initial is probably more like it but better to start on the safe side and yeah this gas sucks. I started cutting some 112 race fuel into a tank of 93 pump as well and the difference was immediate. I only cut in about 2 1/2 gallon per tank and it does the trick. I would run more but at 8 bucks a gallon, I just put what I need to in the tank.

 

[Zeppelin264]

I'd say 91 and 12-15 degrees for the first fire off. Dont want to be too retarded with that much comp.

 

[coloradodave]

12* BTDC is a safe initial for fire up and break-in. After that, it depends on how much mechanical advance you have in your distributor. A total of 34-36* works for me with 10:1 and 91 octane. Break-in is a no load situation so I wouldn't sweat it...

 

[Yatzee]

Just going to toss this out, since I've been out for awhile.

Is 10-12* btdc good to go, for the first firing off? 440 w/ 10.1-1 compression, cam lift under .5.
I've been wanting to ask, because of the crummy gas, these days, so...
Seems alot of the guys are putting more in.

My 512 runs Shell V-power gas only, has 16 degrees btdc and 36 all in. The advance at the distributor is locked out at 36. Starts at a touch and runs great.

 

[miller]

From the way things sound, like you, Yatzee, bet I wind up near 16*. But, I'll start out with 12*, until engine is broke in. That's on a Mallory dual point. Getting pretty close.

Sure appreciate all of you...thanks!

 

[Belle66]

The spark plugs will tell you what timing is needed.
http://www.4secondsflat.com/Spark_plug_reading.html

 

[miller]

Yup. Only way.