Firing Order

[SetofAces]

Hey guys,

I've got a non-HO (probably crown vic) 5.0 in my car, and I'm told that the firing order is different than from the HO motors . . . I'm doing a h/c/i swap, but will I have any issues with running the e303 in my motor? It has the same crank as the HO motor, so I'm not sure why the firing order is different.

Also, I'm bidding on a 70mm MAF and was thinking about getting a 70mm throttle body, will there be any trouble bolting the TB right up to my explorer intake?

Thanks

 

[Turd Tops]

non-H.O's use the 302 firing order. 302 H.O's use the 351 firing order. The E-cam will be just fine if you use the 351 order

 

[68stang351]

I've done the exact same thing. The engine currently in my 90 was a non-H.O. motor, after I replaced pistons, rings, bearings, I stuck in an E303 and some ported E7's and it runs great for what it is.

Use the H.O. firing order 1-3-7-2-6-5-4-8

 

[85_SS_302_Coupe]

Aside from differences in the internals such as forged pistons, the cam ultimately determines the firing order. You can stick an HO firing order cam in a non HO engine and bingo, HO 302 (aside from the internals anyways).

 

[Maryland Stang]

You need to check your computer and make sure it's designed for the HO firing order. If someone has swapped the engine they may have swapped the computer to a non HO version. The reason this is important is the injectors fire in a different order with a non HO computer. They may have also rewired the injectors.

You should also measure the opening of the Explorer intake. Mine was 65MM. If your's is 65MM too then you should open it up a little to match the 70MM you plan to buy.

 

[SetofAces]

You need to check your computer and make sure it's designed for the HO firing order. If someone has swapped the engine they may have swapped the computer to a non HO version. The reason this is important is the injectors fire in a different order with a non HO computer. They may have also rewired the injectors.

I've got an A9P in the car . . .

 

[SetofAces]

Aside from differences in the internals such as forged pistons, the cam ultimately determines the firing order. You can stick an HO firing order cam in a non HO engine and bingo, HO 302 (aside from the internals anyways).

That sucks this thing probably doesn't have forged internals . . . no blower in my near future then, oh well . . I just won an E303 on ebay, also I'm about to win some 19lb. injectors for a dollar, my explorer intake is on its way, I just need to order a timing chain and gears, and a MAF and TB and I'm set, I can't wait . . .

 

[vristang]

I've got an A9P in the car . . .

Make sure the 70mm MAF you are getting has a part number that starts with 'F2VF-'...
That is what you need for the A9P and 19Lb setup.

For some background on the injector firing order and how things can get screwed up...
Ford Fuel Injection Injector Firing Order

 

[Maryland Stang]

That sucks this thing probably doesn't have forged internals . . . no blower in my near future then, oh well . .

It's just the pistons. You can still use a blower on regular pistons. You just need to be a little more careful with your tune and timing.

 

[SetofAces]

Good stuff, thanks for the info Vristang and Marylandstang