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DayCoupe
23-08-05, 06:16 AM
Hi to all,

Can anyone tell me how best to determine the firing order of my 1984 351W which is on Carbs? I don't have the original inlet manifold now, so unfortunately I cannot use this to find out the information (I have read that the firing order is cast into the top of the inlet manifold in Tom Monroes book 'How to rebuild your small block Ford').

Some sources say that the firing order is 1-3-7-2-6-5-4-8, however I notice that there is a note in the Real Steel catalogue which states that their Comp Cams and Edelbrock Cams for the 351W are for engines using a 1-5-4-2-6-3-7-8 (which I believe is the same firing order as 221 - 302 engines!).

I want to use an Edelbrock Performer Plus cam in my engine, to match me inlet manifold, but I don't want to buy a camshaft with the wrong firing order set-up!

If anyone can help it would be much appreciated.

Another question I have is what the HO means with regard to firing orders? This is more of a curiosity that anything else. Do you get 351W HO engines?

I look forward to any replies.

Thanks

shiney
23-08-05, 07:18 AM
hi Kev,
i have a 351w and this has been rebuilt with all edelbrock go faster gear and the firing order is: 13726548 so i don't know where the real steel firing order comes from?

obviously the best thing is for you to check yourself, take out all the plugs put a socket on the main crank and turn, keep an eye on the plug that is the 1st on the left from the from the front of the engine when the piston is at the top you know that one is about to fire! then follow that for the rest and that will give you your firing order.
looking from the front of the engine the pistons are numbered 1-4 up the left side and 5-8 up the right.

this will also give you your plug lead position on the dizzy cap, put your rotor arm on and when the piston is at the top the rotor arm will point to the plug lead positon!

hope this clears it up for you!
regards
colin
www.southsideconcepts.co.uk

MetaJacko
23-08-05, 12:16 PM
Don't know too much about a Winsor, but it you can have
what looks like a different firing order but it is only due to
a different numbering sequence.

I've attached a doc that hopefully explaines what I mean.

Paul

MetaJacko
23-08-05, 12:27 PM
hi Kev,
i have a 351w and this has been rebuilt with all edelbrock go faster gear and the firing order is: 13726548 so i don't know where the real steel firing order comes from?


Hi,

An updated doc with your firing order :)

Paul

TINKA
23-08-05, 04:27 PM
As far as I am aware the cam shaft is what will determine your firing order, as the 302 has a different firing order to the 351W. I believe the camshafts are interchangeable at least some are. This will have no effect at all on the heads, inlet manifold, or even the Distributor. Just check with the fitting instructions that will come with the crank and make sure you connect up the HT leads in the correct order. :thumb: :thumb: Sorry I missed you on Saturday :-( catch up soon. :D

DayCoupe
23-08-05, 05:33 PM
Thanks for all the replies everyone :thumb:

I must confess to still being slightly uncertain as to what the firing order is though. The engine is currently totally stripped out with the block on the engine stand, so I think I will place the crank back in the block and determine the firing order that way. That should confirm it. I will post what I find later :confused:

Does anyone know what the HO firing order means, Do HO engines sound different??

TINKA - Yeah, shame I missed you on Saturday. Hope you had a good day at Brands Hatch :D. I think the firing order is dictated by the crank though and not the camshaft! Although both must be matched to the same firing order.

Cheers guys :thumb:

TINKA
23-08-05, 06:01 PM
Same crank in both engines it is the cam shaft that determines the firing order. Hope fully later Wilf will see this post and confirm what I have said. :thumb:

Purple AK
23-08-05, 06:05 PM
Same crank in both engines it is the cam shaft that determines the firing order. Hope fully later Wilf will see this post and confirm what I have said. :thumb:
Seconded (Apart from the 351 journals being bigger) ;) hopefully Wilf will explain why :angel:

wilf
23-08-05, 06:47 PM
There are different firing orders, and it has nothing to do with the crank, it is all to do with the cam.

It makes no difference anyway - all you do is to place the HT leads in the correct positions around the distributor cap.

So, your firing order wil be determined by your cam. End of. And will probably be 13726548, as most cams are ground that way these days. Of course, there will be some out there that want 15426378. It really does not matter.

As for a "HO" firing order - no such thing. There were "HO" versions of almost every engine produced by Ford, few varied by more than the marketing weenies putting the letters "HO" in the pamphlet.

There were some notable exceptions - special versions of the 289, the 351C Boss engine, the 427SO etc. However I cannot recall any of these having different firing orders from the base engines they were developed from.

DayCoupe
23-08-05, 10:22 PM
Well, firstly I would like to apologise to TINKA for questioning your post :angel:, as it appears that your are correct and I was wrong. I wasn't aware that the same crank was used with just different camshafts!

I put my crank back in the engine this evening, along with the old camshaft, and it appears that my old CAM uses the 1-3-7-2-6-5-4-8 firing order.

Thanks for all the replies though, and thanks for your wise words Wilf.

So, after all that, I can use an Edelbrock Performer cam in my engine :D

Cheers to all :thumb: