302 engine swap - Ford Forums

12-11-2005, 16:01

I have a 1988 Mercury Grand Maarquis with 302 EFI engine thats in very
good condition. The AOD tranny went out in the Merc and I think the old
land barge is past its prime. At the same time I came across a 1985
F250 that has a bad 351W I can get for next to nothing.

My question is how hard would it be to sawp the 302 efi into the 85
truck? Would I be better off carbing the 302 or willl the efi work with
the proper fuel pump setup? What else might i run into during this R
and R if I decided to do it.

Any advice or help would be greatly appreciated. I have swapped many
engines from on form of vehicle to another in my life. I am just trying
to smooth some of the bumps before i get to them.

01-22-2006, 02:01

<dtb1013@hotmail.com> wrote in message
news:1134339966.211507.113340@g44g2000cwa.googlegroups.com...
>I have a 1988 Mercury Grand Maarquis with 302 EFI engine thats in very
> good condition. The AOD tranny went out in the Merc and I think the old
> land barge is past its prime. At the same time I came across a 1985
> F250 that has a bad 351W I can get for next to nothing.
>
> My question is how hard would it be to sawp the 302 efi into the 85
> truck? Would I be better off carbing the 302 or willl the efi work with
> the proper fuel pump setup? What else might i run into during this R
> and R if I decided to do it.
>
> Any advice or help would be greatly appreciated. I have swapped many
> engines from on form of vehicle to another in my life. I am just trying
> to smooth some of the bumps before i get to them.
>
DTB,
The first thing is to make sure all the sensors are basically the same, (ie
Location, # and purpose), the next thing would be to take the ECM out of the
Merc and install it in the F250. The second would be to make sure that your
tranny will bolt up to the big block. Up to the 302 you are talking about
small block, and from the 351 up is big block territory. So you might have
to swap the C6 tranny for a C5. I know the 302 is not an option for the F250
no matter what year. It just doesnt have the power to pull the heavy loads.
The other thing you are going to run into if you carb the 302 is the
electronic fuel pump for the 351, you will have to regulate the pressure
down to about 7-10psi or get rid of the electronic all together and use a
mechanical fuel pump. Fuel pumps for the EFI systems run at, I think,
40-50psi. Then you have the exhaust, with the change of block size, you have
to probably change the exhaust crossover pipe to accomodate the smaller
block size. Good luck on the engine swap..
Pk

01-22-2006, 22:01

In article <7IHAf.43620$0G.33894@dukeread10>, pkurtz2 <pkurtz2@cox.net>
wrote:

> <dtb1013@hotmail.com> wrote in message
> news:1134339966.211507.113340@g44g2000cwa.googlegroups.com...
> >I have a 1988 Mercury Grand Maarquis with 302 EFI engine thats in very
> > good condition. The AOD tranny went out in the Merc and I think the old
> > land barge is past its prime. At the same time I came across a 1985
> > F250 that has a bad 351W I can get for next to nothing.
> >
> > My question is how hard would it be to sawp the 302 efi into the 85
> > truck? Would I be better off carbing the 302 or willl the efi work with
> > the proper fuel pump setup? What else might i run into during this R
> > and R if I decided to do it.
> >
> > Any advice or help would be greatly appreciated. I have swapped many
> > engines from on form of vehicle to another in my life. I am just trying
> > to smooth some of the bumps before i get to them.
> >
> DTB,
> The first thing is to make sure all the sensors are basically the same, (ie
> Location, # and purpose), the next thing would be to take the ECM out of the
> Merc and install it in the F250. The second would be to make sure that your
> tranny will bolt up to the big block. Up to the 302 you are talking about
> small block, and from the 351 up is big block territory. So you might have
> to swap the C6 tranny for a C5. I know the 302 is not an option for the F250
> no matter what year. It just doesnt have the power to pull the heavy loads.
> The other thing you are going to run into if you carb the 302 is the
> electronic fuel pump for the 351, you will have to regulate the pressure
> down to about 7-10psi or get rid of the electronic all together and use a
> mechanical fuel pump. Fuel pumps for the EFI systems run at, I think,
> 40-50psi. Then you have the exhaust, with the change of block size, you have
> to probably change the exhaust crossover pipe to accomodate the smaller
> block size. Good luck on the engine swap..
> Pk
>
>

Wow. A 351 is a big block, ha? Maybe on your planet. The fact is
that the 351W is a tall-deck version of the 302, and has the same
bellhousing pattern.

Damn, the experts around here are on drugs.

01-23-2006, 04:01

On Sun, 22 Jan 2006 03:01:16 -0600, pkurtz2 rearranged some electrons to
form:

> Up to the 302 you are talking about
> small block, and from the 351 up is big block territory.

Uh, PK, the 302 and the 351W are similar blocks with
different deck heights. They are both considered to
be "small blocks", and share the same cylinder heads
and bellhousing bolt patterns, so a transmission will
bolt up to either.

--
David M (dmacchiarolo)
http://home.triad.rr.com/redsled
T/S 53
sled351 Linux 2.4.18-14 has been up 4 days 22:44