Firing order?

[Larry's Yellow Rdstr]

Please don't ask me why I'm asking this, but:
The firing order on my C5 is 1-8-4-3-6-5-7-2.

Has anyone ever heard of a different sequence? A 383 stroker I have built for my El Camino has a miss through out the RPM range. Several mechanics and I cannot figure out the problem, then I think I remembered reading somewhere of a slightly different firing order??

Any positive help will be appreciated>

Keep the wave!

Lar

 

[Edmond]

Larry,

I think that you really have to look at the most simple and fundamental answers for something like that. When you have the knowledge that someone like you and those mechanics have, I think it's easy to overlook the basics.

Are you positively sure the distributor and wires are correct? That would be my best answer and it's probably the most simple one. It's so easy to get them mixed up.

 

[RodsnRides]

Check wires

Hi Larry -

Chevy V-8's have always been 1-8-4-3-6-5-7-2. I also read something somewhere of a change but don't recall what it was and I wouldn't recommend it anyways. Stay with what has been successful in several million applications.

I'm thinking you have an ignition wire or spark plug breakdown. I recommend you use an ohmeter and check your wires for resistance, which should be 1K ohms or less per inch. For example, take the ohmeter leads on each terminal end, if the wire is 24" long, resistance should be less thn 24K ohms. I also like to move and "flex" the wire as I'm checking it, sometimes a wire that reads good will show a defect as its twisted-carbon breakdown. Check your plug gaps as well, .035 for points, .040-.045 for electronic. maybe give it a nice steady run down a straight road for 2-3 miles, shut it off, pull over and pull the plugs, looking for an inconsistent one. Good luck.

Love the Elks as well-I have 4: 2 '70's and 2 '72's. All small block Chevy's. 3 Autos and 1 stick. What year is yours?

Rick

 

[Ken]

From Hot Rod Magazine:

A typical Chevy firing order is 1-8-4-3-6-5-7-2. For the vast majority of applications, this firing order works nicely and there’s probably no need to change it. But in a race application, there are various firing orders that can effectively improve power and reliability in an engine. Typically, there are seven other firing order arrangements which can be used without changing the crankshaft layout on a Chevrolet V8. These firing orders include the following:

• 1-8-4-2-6-5-7-3
• 1-8-7-2-6-5-4-3
• 1-8-7-3-6-5-4-2
• 1-5-4-3-6-8-7-2
• 1-5-7-3-6-8-4-2
• 1-5-7-2-6-8-4-3
• 1-5-4-2-6-8-7-3

Reher-Morrison has tested the various combinations and found some interesting results. When the firing order is revised to 1-8-7-3-6-5-4-2, you’ll find some power and reliability. Now, if you race a Pro Stock car, this is no secret since the revised order has been in vogue for some time. With the revised firing order, fuel distribution dilemmas are resolved. The engine tends to run cooler, and perhaps just as important, the engine is actually smoother. How much extra power is there? Anywhere between 8 to 10 measurable horsepower. There was once a caveat here though: The average enthusiast couldn’t easily get a cam with the revised lobe positions, but not so today. Reher-Morrison sells such a package (called Big Stick Cams) for Chevy big block/Big Chief head combinations.

 

[Larry's Yellow Rdstr]

Thanks guys for the help. My elky is a 74. Thats not the most desirable year I know but this car was the best of the four I looked at.I appreciate the suggestions and the various sequences that have been sucessfully used.
I won't go into the gory details behind this particular engine, but nothing has gone right. I bought the elky for an everyday driver, but because of one problem after another I'm still depending on my C5 for transportation.

Lar

 

[c4c5specialist]

Hi there,
c5 is 1-8-7-2-6-5-4-3
Your standard GM small block in the 74 is 1-8-4-3-6-5-7-2
Allthebest, c4c5

 

[Larry's Yellow Rdstr]

Sometimes I think if I had a one cylinder Zundapp motorcycle I would get the firing order backwards.