1980 318 firing tdc - 1983 Dodge Pickup

Engine timing is done electronically. It is based on Cylinder 1 being a few degrees before TDC (Top Dead Centre of firing stroke).

Valve Timing is set using marks when you change the timing belt or chain. That is set with Piston 1 at TDC on FIRING stroke.

Here is the firing order. It is nice and easy, 1, 2, 3, 4, left to right.

https://www.google.com/search?q=2007+suzuki+forenza+firing+order

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As it is a 4-stroke engine No. 1 cylinder TDC could be at the end of the exhaust stroke or the end of the compression stroke.

Assuming it is TDC compression stroke it will take two crankshaft revolutions for it to be in the same position again, meanwhile in those two revolutions the other five cylinders will reach TDC compression in the firing order of the engine. An inline engine has the firing intervals 120 crankshaft degrees apart but the vee engine, designed to be shorter (more compact) and have better balance characteristics and the shorter, lighter and stiffer crankshaft produces less torsional vibration, though the firing intervals of a vee engine can be uneven depending on design. Some vee 6 engines were shortened vee 8's.

Late firing or retardant ignition is the condition caused by incorrect ignition timing. Ignition timing is a setpoint established by the engineers as the optimum setting for ignition efficiency. This setting is a few degrees before TDC or top dead center. TDC is the point on 360 degree scale at 0 . This indicates the #1 cylinder has its piston travel at the top
Limit of the stroke. If your condition has firing occurring after the few degrees Before TDC then this can be called late firing. You have a timing issue.

Turn engine until valve tappets are on the back of the cam lobes. (TDC firing) Adjust as per any engine inlet .010" hot and exhaust .012" hot. Turn over until next piston in firing order comes to tdc (90 Degrees) and repeat process of adjustment.

The valves for any given cylinder will be closed when that particular cylinder is at TDC and on the "firing" cycle. Since 4 cycle engines have four "cycles" the piston can be at TDC twice. Once for firing and once when the exhaust cycle is completed and the intake cycle is starting.

Cycle 1: Intake valve is open and piston is travelling DOWN. (Intake)
Cycle 2: Both valves are closed and the piston is travelling UP (compression)
Cycle 3: Fuel has been ignited and the piston is travelling DOWN ( power)
Cycle 4: Exhaust valve is open and the piston is travelling UP (exhaust)

TDC is Top Dead Center, or the point that the piston is at the top of it's travel.

Sounds like a timing problem. Back firing through the carb usually indicates that the timing is after TDC instead of before TDC. Not running would be an indication of the same. The normal timing is just a few degree before TDC (BTDC).

It doesn't matter where the other pistons are as long as #1 is all the way up or Top Dead Center. What matters is what the valves are doing when #1 is at TDC. Watch the valves carefully as you turn the engine over and make sure that the intake opens first. At TDC both valves should be closed and as you go past TDC the exhaust valve will start to open. Remember that this only happens in this order every other time #1 hits TDC.
When you have this order correct the #1 piston should fire. Hope this helps.

TDC is when number one cyclinder is at top dead center to fire. Soooo, the firing order is 2,3,1,4.front to back of engine.

are you on the right stroke? If it is not tdc on compression stroke it will not ever start. You have tdc 3 different times, once on intake, exhaust, and compression. I bet that is your problem, must be on tdc on compression!

hi from uk hope this will explain TDC valve positions ? when the crankshaft is at tdc this means that numbers 1 and 4 pistons are both at tdc but only one of the cylinders are on firing mode so if let us say in relation to 4cyl engine the fire order is 1 3 4 2 the c/shaft is at tdc ? but for which cyl ? 1 or 4 ? to check look if the camshaft mark is at its mark or check rotor arm ?if at 1 or 4 ? if it isat no1 cyl then both of the valves for that cyl are fully closed whilst no4 cyl valves are at the point of exhaust valve just closed and inlet just about to open this is correct for tdc number 1 cyl firing stroke ?ok so far ? now then if c/shaftmark is atTDC it may be number 4 cyl ready to fire? that is because the camshaft rotates at half speed to the crankshaft soyou need to rotate crank 360 deg to bring cyls 1 + 4 to tdc again then it will be cyl 1 at tdc on firing stroke along with rotor arm at No 1 plug lead and both valves for No 1 cyl will be closed (the cam lobes will be facing up whereas No 4 cyl valves will be pointing down ) hope this is clear for you to understand? if you look at any 4 cyl engine the sequense is the same for No 1 TDC but firing orders may change ie fords 1 2 4 3 is fire order they use as apposed to 1 3 4 2 ? OK? CURIOUSE why you asked? but best wishes and merry xmas from uk