i have a 1997 F-150 with a bad 4.2 cant find a good used engine for under 600! I talked to a man at a salvage yard he said you can swap a 3.8 mustang in its place all you have to do is change the intake timing cover and flywheel and exhaust manifolds. i found one for 500 thats why i ask

 

It is basically the same engine with a shorter stroke (less torque). It must be from a rear wheel drive car like a T-Bird, Cougar or Mustang because the blocks are cast different for FWD cars such as Taurus, Sable and Continental.

 

what about the ECU, is that the same? If you gotta swap ECU, wiring harness, ect. you might end up spending more.

 

No need to change out the ECU or any wiring.

You are going to lose torque and fuel economy in the city though.

Darrin

 

i've heard of the opposite done, people putting the 4.2 in a mustang. You won't be losing that much power, nothin that some basic upgrades and a light tune can't fix... or a t-bird supercoupe s/c setup...

 

he's trying to save $$ with the swap, if you want some power drop a lighting 5.4 in it

I had a 4.2 with a 5 spd regular cab and it was kind of a dog, a 3.8 (I'm guessing auto) would have to be even worse. Plus you'll probably be getting on the gas more to make up for it, and decrease MPG.

 

Of course an intake and sensor swap means gaskets, seals, etc, which affect the total price. Check all the costs first.

 

just finished this exact swap. got a 2004 mustang 3.8 for $350. all I used from the 3.8 was the block, heads, valve covers, timing cover, and oil pan. evrything else was swapped from the 4.2. all in all I have about $450 in the swap, plus the $500 for the 97 F150 with a bown motor (mint body). so less then $1000 for a truck with 65,000 miles (on motor).

 

If you can get the 4.2 for 600 and do a direct swap out, I'd do that vs a $500 swap that's not direct and will end up costing more than the $100 difference.

Mike

 

I did it cause the only 4.2 under $1000 had 214,000 miles. I got a 04 motor with 1/4 the miles for $350. no real cost difference between using either one aside from cost of motor. all the stuff I had to buy would have been usedon either motors. oil, antifreeze, upper and lower intake gaskets, just the usual stuff.