Too cold to start car

The MSD likes it's voltage, so you gotta start with a fully charged battery, and a warm one works best.

Starting my 360 without a choke takes a bit of a technique.
I keep a small sealed bottle of stabilized 87E10-winter gas on hand which seems to be a little more volatile than other gas. And I add 2-cycle oil to it at about 5%.
To start;
I splash about a half ounce down each primary of my AirGap 2plane intake. And I pour an ounce or so into the front bowl thru the vent with a tiny funnel; this just to ensure the bowl has at least some fuel in it. If you have an electric pump, you can use that if your gas is fresh. You should be having reasonably fresh,non-oxygenated, stabilized,winter fuel in the tank.Then I look down the primaries and stroke the throttle until I see the accelerator pump is primed and working.With liquid fuel now in the intake, I let it sit for a couple of minutes to evaporate some of the VOCs (Volatile Organic Compounds) and fill the intake with something that will actually burn.
Then I crack the throttle just a hair and hit the key. The idea is to let some air into the intake, that will draw the VOCs into the cylinders with it, to begin the burning. During the first 3 to 5 seconds she will pull those in and start random firing. That is your cue to start pumping the gas pedal. If you have a double pumper, try not to get the secondaries involved. It's really hard to flood my no-choke Holley 360 cuber with the small pump,so I just give her pumps; about 1 per second for up to 10 pumps. If at any time she stops firing, you have managed it (to flood her) tho, so stop pumping. The idea is to only open the throttle far enough to activate the accelerator pump (about 1/4 throttle to keep the transfer system alive) and you control the AFR with the amount of minimum but not closed, throttle opening.
When she catches be prepared to immediately open the throttle further, but not so far as to open the secondaries.Only far enough to keep the transfers alive, and maybe the mains dribbling; I've never actually watched.. While you do this, the engine will begin to draw in that puddled fuel from the intake, in addition to what is coming from the normal circuits. So it will immediately rev up (I target 2000by ear, but don't worry about the actual number.) And in about 3 seconds it will go lean, having burned all that fuel up. Be ready for it, and when the Rs begin to fall, start pumping again, but try not to let the butterflies close all the way between pumps, you are still trying to prevent a stall, which may require you to start all over, from the beginning. After about 30 seconds of this crap, she will start running easier and you can gradually reduce the rpm and the pumping.
Now here are a few tips;
>getting this system right for your combo may take some practice; embrace it,lol.
>that cold engine really likes a ton of timing. I give mine about 10extra degrees during cold start, and it ain't too much. This totals 24 with my 14Initial.
>The 2-cycle oil that I mixed in helps to replace that which will be washed off during the very rich starting procedure.
> I run 10W30 full time. Because I have a hi-volume pump, I fear with thicker oil, that pump will empty the pan at 25F, cuz it it won't get back from the top fast enough. I had this problem before with 15W40. So I installed a 7 qt pan, and installed some drainback channels in my Eddies. I lost a couple of 340s when the pumps started sucking air. Yes a couple. I was a slow learner.
>If it doesn't begin firing in the first 3 to 5 seconds, it likely ain't gonna run;the VOCS from the fuel in the intake are all gone, and the rings may be dry. Start over. If it does it two or three times in a row; I recommend to pull the plugs and squirt some oil into every hole, reinstall the plugs;. then crank it a few revolutions to move the oil around, then let it sit for an hour, while the oil wicks itself all around the cylinders. Then you get to start over.
>If it fires right away, runs, and then stops; it has burned up all the VOCS, so either the in-tank fuel is dead or it never made it to the carb yet, start over. If it does the same thing again, and your accelerator pump is primed, then you can bet the fuel is dead, and you better quit before you fill the oilpan with gas.
>IMO, this winter starting without a choke is really really hard on the engine, and I never do it anymore. But I might go out once a month and crank it over a half a revolution, to put a different pair of pistons near TDC and so a different set of springs under pressure. I used to do it by hand but I'm gettin' too old for that crap,lol.
>As to your current situation, your oil is probably all washed off the cylinder walls by now, and your cylinder pressure is very low;so you will need to pull the plugs and oil the rings up as previously mentioned.
> With the advent of EFI and sealed fuel systems, the gas companies have reformulated the fuels for that, leaving us carburator and vented tank guys with fuel that gets harder and harder to initiate a burn. With the vented tanks, the VOCs escape within a week, and even in summer, the engine gets cranky after a week of sitting. Two week old fuel is already bad. Up here Shell is fighting it with adding stabilizers before dispensing, and that is helping. My engine is set up to burn 87E10, and the alcohol in the fuel helps starting in summer,but as the temps fall, no more help. Towards the end of the season I add additional stabilizer.
>25F is about-4C I think, and my 360 starts pretty easy at that temp, with the above described method...... but at 68*F she has about 185psi cranking cylinder pressure, so this may have something to do with it,lol.
So, I just gottasay;your results may vary.
and
best of luck to you.