340 wrong firing order?

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RunarStock

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So I duck under the hood and replace sone plugs, removing one wire and installing, so that I do not confuse my brain.

But I do by some reason remove two wires, and suddenly I don't know which is which. So I compare to 340 spark order picture. Suddenly, Im more confused.

1-8-4-3-6-5-7-2 it says in all pictures.

Of course, my order isnt anywhere near looking like that.

1-6-5-7-2-3-8-4 is where I end up if I start with cylinder 1.

Also, cylinder 1 isn't oriented at 6'o clock on the dist.cap either.

Problem is I know nothing of the innards of the engine. Only that it's a 340 (late 71 probably, it's painted blue), with 69 exhaust manifolds, qft slayer carb and an old edelbrock tm5 intake.
In 2014 the car did 285whp right after getting off the boat. Should I assume there are other mods done? May that be the reason for the spark order?

I'm becoming hesitant to drive the car...

Snapchat-7465335410273523181.jpg
 
The wires do not look they are placed correctly in the pic. Does the car start/run OK? Can't see how it would with the wires like that. Does not 'really' matter exactly where the #1 terminal is as long as the firing order is correct. It's odd for it to be that far over. If it was wired like that when you got it, the the P.O. messed it up and was trying to make it work by retarding the timing like 80 degrees.

Take the valve cover and distributor cap off. Bring the motor to TDC on the compression stroke and look to see where the distributor rotor is pointing. Then check the mark on the balancer to see where it's at. Pretty easy to verify this stuff.

If the rotor is pointing somewhere other than the #1 cylinder, then you have some deeper checking to do. If it's 180 off, that's an easy fix. If it was timed wrong when it was built, that's another story but if it made *** horsepower at the wheels prior to you getting it, then clearly it's just a matter of finding TDC and putting the wires in the right spot.
 
Well, now I feel dumb. Haha.
I mixed 1 and 3.... with that rectified, the order is the right one it seems....

Well, on another note, with the needle in the dist cap falling out, can I replace with almost any cap? As lo g as it has clips for fastening and not screws? I'm out swimming in deep waters :D
 
The downfall of performance ignition systems is that they use their own cap. I'll bet you will have to get a specific one from them.
 
rmchrgr said:
The wires do not look they are placed correctly in the pic. Does the car start/run OK? Can't see how it would with the wires like that. Does not 'really' matter exactly where the #1 terminal is as long as the firing order is correct. It's odd for it to be that far over. If it was wired like that when you got it, the the P.O. messed it up and was trying to make it work by retarding the timing like 80 degrees.

Take the valve cover and distributor cap off. Bring the motor to TDC on the compression stroke and look to see where the distributor rotor is pointing. Then check the mark on the balancer to see where it's at. Pretty easy to verify this stuff.

If the rotor is pointing somewhere other than the #1 cylinder, then you have some deeper checking to do. If it's 180 off, that's an easy fix. If it was timed wrong when it was built, that's another story but if it made *** horsepower at the wheels prior to you getting it, then clearly it's just a matter of finding TDC and putting the wires in the right spot.
Click to expand...

Runs just fine, a little lumpy, but that may be a result of a sticky choke linkage from choke motor to choke flap, runs fine when I get the temp right (no thermostat at the moment). Thanks for the guide, I need to change valve cover gaskets anyway...
 
upload_2016-5-27_6-57-53.png


If you happen to exchange #s 6 & 8, the motor will run amazingly well, just lack power. no popping.. fwiw
 
Is that a Skip White Ready to Run HEI distributor?
Sure looks like it with what looks like the chrome box on the side.

Also and FYI, it doesn't really matter where the number one wire is as long as the distributor rotor points to that plug terminal on the cap at TDC on cylinder number one.
 
Why is what should be the #4 wire going to the odd side bank?

Distributor doesn't care where the wires are as long as they are in the correct order. Doesn't appear the wires are in the correct order for a clockwise rotation rotor.

You could certainly clean it up by changing the oil pump drive orientation and move the wires in the cap.
 
crackedback said:
Why is what should be the #4 wire going to the odd side bank?
Distributor doesn't care where the wires are as long as they are in the correct order. Doesn't appear the wires are in the correct order for a clockwise rotation rotor.

You could certainly clean it up by changing the oil pump drive orientation and move the wires in the cap.
Click to expand...

I was typing, you were posting, LMAO. I agree^^


You need to learn this stuff so you can deal with it. It's EASY

First learn the cylinder numbering, and make a drawing if you have to

Most GM, and all Mopar v8s are numbered front driver side is 1, and 1357 front to rear, pass side is 2468

Do NOT worry (for now) about "where number one" is supposed to be "according to some diagram." (in the cap) It varies.........depending........

on whether the distributor tang is oriented as original which is NOT THE CASE on all distributors!!!

and on whether the oil pump drive (intermediate shaft) was dropped in as per "factory."

If either or both of the above is not "per factory" then the location of no1 WILL NOT be in the cap as per factory diagrams.

HOW to deal with this? EASY!!!

Remove the no1 plug.

Arrange to jump the starter. This is easy on Mopars. All you need is a screwdriver jumpered across the two large exposed terminals on the start relay.

Put your finger in the no1 hole. "Bump" the starter until you feel compression. You may have to "go round" a couple of times until you get the "feel" of this.

When your finger gets blown out of the hole, stop. LOOK!! At the dampener and watch for the timing marks.

Now either bump or wrench the engine over until the marks ARE NOT at TDC, but rather, "where you want" timing to me, that is, 10-15 degrees BTDC, more if you have a real hot cam

SO.........now.......

You have the no1 ready to fire, on compression, with the marks stopped at 10-15 BTC.

LOOK at the distributor rotor, and install / uninstall the cap a couple of times if necessary to determine which contact the rotor is APPROACHING as it goes CLOCKWISE. Also make sure the BODY of the dist. is oriented to give you some back and forth room for adjustment, AKA not having the vacuum advance jammed against the firewall or the engine.

THAT IS your functional no1 "hole."

Now, just drop the no1 plug wire in that determined hole, and go right around clockwise. Be careful of 5 and 7, they are easy to reverse.

I typically do one bank at a time ONE (84) THREE (6) FIVE SEVEN (2)

Then go to the pass side and (1) EIGHT FOUR (3) SIX (57) TWO

All done. Set the TIMING
 
Thank you! I must say I love you people.
Since its running Ok, I'll go yank all the wires and re-wire, and hope it fires up, and that #1 actually IS #1. I followed the spaghettis earlier, several times, and came to the conclusion that they were all in the right order, several times, but then again, I'm just starting learning this.
 
Take the cap off and see which way the rotor is turning. It should be clockwise looking from the top.

It looks like it may be wired for reverse rotation, counter clockwise rotor.
 
crackedback said:
Take the cap off and see which way the rotor is turning. It should be clockwise looking from the top.

It looks like it may be wired for reverse rotation, counter clockwise rotor.
Click to expand...


YES lol, small blocks turn clockwise, unless they are a marine reverse rotation. You won't find that in a car
 
TrailBeast said:
Is that a Skip White Ready to Run HEI distributor?
Sure looks like it with what looks like the chrome box on the side.
Click to expand...

What eyes you have! There' a chrome box to the left of the vacuumthingy yes. I'll shoot from the hip and order a replacement cap from them. The cap burnt in center where the coil fires and the needle is missing, the wire points are cratered and ugly.
 
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