Whats mods are needed to swap out 3.8L in my 1986 Mustang for a 351w?

stang4u2nv · 10-03-2002

I have an 86' LX and i was wondering what sorts of changes i would have to make to my car in order to swap my dinky 3.8 for some big 351 power? I found this engine in a 1978 Thunderbird and it only has 10,000 miles on the rebuilt engine. The dude is just giving it to me because the trans went out on the T-Bird. What types of modifications do i need to make in order to get this beast into my ride?????

85NewfieGT · 10-03-2002

You will need a 351w double sump oil pan from a crown vic mid eighties or the swap oil pan kit from ford. The 351w is 3/4" taller and 1.5" wider so the exhaust will have to be changed, other than that are you going to go with a carb as you will have to switch ignition systems. You can use stock 302 headers if you get a custom h pipe or factory h pipe with swap headers. It is a pretty straightforward swap if you have the patience to get everything together, I just finished the swap in an 85 GT and it went well, had to figure out some bracket fabrication to get my AC to work but have a look and see for yourself, it looks like it came in the car.

http://www.allfordmustangs.com/forum...at=500&thumb=1

If you have any questions feel free to ask, email me at b_m_gillespie@hotmail.com

Good luck, oh and it was worth the effort!!
Brian

Twister · 10-03-2002

um, you dont want to do this swap, Ford used 351M'sin cars in 1978 and these are larger than a windsor and there are NO parts for a swap

stang4u2nv · 10-03-2002

Quote:

Originally posted by Twister
um, you dont want to do this swap, Ford used 351M'sin cars in 1978 and these are larger than a windsor and there are NO parts for a swap

there is a sticker on the side of the valve cover that says the engine is a 351W not 351M so maybe they swapped the windsor for the modified

85NewfieGT · 10-03-2002

You may want to double check the engine to make sure it is a winsor and not a modified, the modified won't be worth the effort to squeeze in.
Brian

Twister · 10-04-2002

easy way to check....valve cover bolts, W=6 per side, C/M=7

Jarrett · 10-04-2002

Windsor's thermostat housing bolts into the intake, the 335 series (mods and clevelands) thermo housing bolts into the block.