Firing order on lsx engines

[andytk]

I've heard that the firing order on a chevvy lsx engine is different from that of a traditional V8.

What is the firing order on a traditional V8 (and which modern V8's still use it?)

and

what is the firing order on a Chevvy lsx engine, and are all the different varients the same.

Oh, and while I'm at it which ls engines are used in which cars?
Am I right in thinking;

ls1 = 5.7 litre C5 Corvette/Holden Monaro/Chevvy Impala
ls2 = 5.7 litre C5 ZO6 Corvette
ls6 = 6 litre C6 Corvette/Vauxhaul Monaro VTS
ls7 = 7 litre C6 ZO6 Corvette

Too many varients in too many cars, its enough to make you're head spin.

Andy

[stevieturbo]

LSx is 1-8-7-2-6-5-4-3

Some V8's are different. Cannot comment on all types.

Rover V8 is 1-8-4-3-6-5-7-2

[GreenV8S]

It looks as if the LSx uses the same cylinder numbering convention as the RV8, but worth confirming.

[boosted ls1]

Think the firing order is the same for all types. If in doubt look at the inlet manifold.

Boosted.

[steve_D]

I thought all Chevy types were same firing order.
My Chevy 6.7L and Range Rover 3.5L are both
1-8-4-3-6-5-7-2.
The only change to that is custom grind Chevy camshafts which swap 5 and 7 to smooth intake pulses.

Steve

[GreenV8S]

I think you mean swap 4 & 7.

Can you tell I've spent the last week looking at a wasted spark system!

[Boosted LS1]

Firing order was changed for the Ls1's.

Boosted.

[andytk]

Boosted LS1 said:

Firing order was changed for the Ls1's. Boosted.

Boosted's right on this one.

Chevvy changed the firing order on the Ls series of engines for some reason, something to do with manifold design and breathing of one of the cylinders or something.

I remember reading about it somewhere ages ago but I have a very poor memory.

Andy

[steve_D]

GreenV8S said:

I think you mean swap 4 & 7. Can you tell I've spent the last week looking at a wasted spark system!

Probably right. I think i'm confusing it with the need to keep 5 and 7 spark leads apart as they can cross fire.
could be wrong again. Won't be the first or last time

Steve

[stevieturbo]

I dont dispute your claims.....


But on an LS1 anyway, I cant see how any firing order would affect teh amount of air the engine can consume. I was under the impression the firing order was to improve smooth running.

[rud]

THe real reason for the new firing order is better idle stability and less vibration.