I found this information on another website... Is it accurate?

<table><tbody><tr><td>289</td><td>1-5-4-2-6-3-7-8</td></tr> <tr><td>302 (Pre-82)</td><td>1-5-4-2-6-3-7-8</td></tr> <tr><td>5.0</td><td>1-5-4-2-6-3-7-8</td></tr> <tr><td>5.0 HO</td><td>1-3-7-2-6-5-4-8</td></tr> <tr><td>5.0 Truck</td><td>1-5-4-2-6-3-7-8</td></tr> <tr><td>351</td><td>1-3-7-2-6-5-4-8</td></tr></tbody></table>
Assuming so, can anyone please confirm the HO never made it into a truck; at least not from 92 - 96... I pulled a short block from a F-150 of this era to replace the one from a 98 explorer. Need to confirm the firing orders are the same. If not the same, it is going to suck.

 

Is this article regarding the cam accurate?

Ford 302/351 W Roller Cam: Engine Builder

Its got me concerned that something might be different with the short block I grabbed if its a pre-94...

 

Depends on the cam installed in the motor. The 94-97 pickup and van 5.0's use the 13726548 order, as do the Explorer/Mountaineer 5.0's and the 94-97 roller 351's, all these engines used the same roller cam. This cam is slightly different from the HO roller, but uses the same firing order. The short block is the same between the 94-97 and the Explorer, with the only difference being that sometime around 97-98, the Explorer got different pistons. Not sure if this changed the comp ratio, but they are noticably different pistons from the earlier ones.

 

That makes me feel better. Thanks.

The pistons looked the same on both blocks, at least on top.

 

The actual HO motor was never installed in trucks but the '94+ version makes more power than the earlier motors so that's probably where people start thinking it's a HO, but as Baddad457 indicated it still doesn't have the HO cam or the forged pistons found in most HO motors. And all 5.0s from '94 on use the HO firing order so if the motor you pulled was older than that you may have a problem using it in the Explorer.

 

Is there anyway to confirm based on stampings or observing the pistons cycle while turning the crank?

 

No the rotating assembly is the same for both firing orders it never changed, the difference is with the cam alone so if it turns out you have an earlier motor you can fix the problem by simply installing a '94+ cam like the one in the Explorer motor for example.

 

Ok so it sounds like I am good. I assumed the rotational assembly changed w/ the firing order.

 

The difference is in the skirt design.

 

Will the skirt make much if a difference in normal engine operations?

 

No it won't make any difference at all to engine operation, it was probably done to reduce cylinder wear over the life of the engine or to simply save some money.

 

After this discussion I feel much better. As mentioned, for a moment I thought I had gone through all the effort of getting another short block for nothing. I do have more questions but I will make a separate thread for that. Hopefully this answers this question for others in the future.