maf Q's

superdan

superdan

Member
"If this is in the wrong place sorry "

Ok so I have a 94 orig 5.0 auto 4wd maf f150 And it blew up the other day "twice"
So now I found a complete 351 and I want to know if I swap to a h.o. cam " so the firing order is correct for the computer " will the stock ecm run the 351 ?
 
superdan said:
"If this is in the wrong place sorry "

Ok so I have a 94 orig 5.0 auto 4wd maf f150 And it blew up the other day "twice"
So now I found a complete 351 and I want to know if I swap to a h.o. cam " so the firing order is correct for the computer " will the stock ecm run the 351 ?
Click to expand...
If you are already MAF, I wouldn't mess with a 5.0 cam. I'd roller, and a torque cam, since you are a 4x4.
 
So what was your original firing with the 302? Was it an HO firing order? What year 351? You can only use a f4 (94-97)block to be able to use the B303 cam. If you have a roller block and can use the B303, and had an original HO firing order (ecm specific)then yes it would run. I think some fueling table may be off because of the larger ci, possibly timing too. It can all be fixed by getting it tuned with a chip.

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BTW, I've heard you loose a lot of low end tq adding a B303 to a 351.
 
Imo the B cam is not the best choice. I have a B in my 85 mustang but it is a carb car the B works well in it since it is carb.
 
Its a 96 351 and my ecm has the h.o. firing order I already have the cam that's why I was going to use it but I also have a stock explorer and roller truck cam as well .would the dizzy from the 5.0 work with the 5.8? Or would the 5.8's work with the roller cam? I have a set of gt40 heads I was thinking about putting on it to would they effect it enough to bother with them?
 
The 5.0 and 5.8 have different deck heights, so no the distributors will not interchange. I don't know the specs on the explorer cam. I think I would just use the 5.8 cam that it came with. What ever combo you go with make sure you have the right gear on the distributor, they use different material depending on flat or roller tappet. You would p/u a few hp with the heads. So with your ecm being a HO fire order you can use a 351/5.8 (they are all HO fire order). You will need a 351 distributor.
 
Agree with the above ^^^

Firing order is not an issue for you since 5.0L EFI truck motors use the same firing order as 5.0 HO and 351.

B303 cam is an issue -- it's designed for a 3,000-6,000 rpm power band, which is not well-suited to a 351 truck motor in a 4x4. Just go with the stock 351 cam, for now at least.

5.0L distributor will not work in the 351 -- you'll need the 351 distributor with either the cast iron gear for flat tappet or the steel gear for roller, depending on which way you go.

Which type GT40 heads do you have? If they're the GT40p heads off the 5.0L Exploder, they aren't a simple bolt-on for a 351 -- just do a search in the Gen1 forum for "GT40p" and read up before you try it.

Your 94 MAF ECM is also an issue -- it will work, the truck will run, but not very well. You'll have to get a tune to get anything out of that 351, or swap in a 5.8L MAF ECM out of a pre-96 Bronco if you have an E4OD transmission. If you don't have an E4OD, your only option is to get your stock ECM re-tuned.
 
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The heads are 3 bar heads id have to have them drilled out for a 351 but my biggest concern is making it run right would it be better to just keep a 302 in it ? It seems like quite a bit of hassle just to have a 351
 
"Firing order is not an issue for you since 5.0L EFI truck motors use the same firing order as 5.0 HO and 351."

Not all 5.0 trucks had 137 firing order. Flat lifter cam 5.0 trucks were 154 firing order.
 
Ah I didn't know that about the firing orders or the ecm so 95 ? Bronco ecm would work ? Do I need the harness to or is it the same
 
I think I might just stick with the 302 it seems like it'd be a pita to find all the 351 stuff I'll probably just slap the gt40s on whatever I find and go with that .
 
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