[Roush380R]

Hey guys,
I'm looking at buying a 2003 Mustang GT with the SOHC 4.6L. The motor's blown - I'm not sure what happened. However, I have a 4.6 from a parts car I used on a previous project which has a good motor with 40k miles on it. I need to know if I can do a direct swap, and what problems I'm going to run into. Also, I'm in CA so this could complicate things. I know that technically for smog, you can only swap a newer motor into an older car, but if these two motors are the same, I'm hoping the smog technicians will never have to know. My question is, can I do this swap? If so, can I use the ecm from the 2003 so that it shows up fine on the smog checks? Any advice? I only have a little bit of time to decide on doing this project and can really use everyone's help asap. Thanks guys!

 

[Boostang]

need a little more info??
what year is the motor ur trying to put in?
if its 99-00 then its a windsor and a 8 bolt crank.. if its 01-04 (like ur car) then its romeo and its a 6 bolt crank

 

[Boostang]

besides those differences everything is the same..
should go right in and plug up..
if its a windsor tho ur gonna have to buy a 8 bolt fly wheel

 

[Roush380R]

Thanks for the quick replies. I have a motor out of a 99. Its also got an auto transmission but I'm hoping to use the 5-speed on the car I'm looking at buying. Can I use the ECU from the 2003 to control the 1999 motor without issues?

 

[Boostang]

yes itll be fine.. but make sure u have an 8 bolt fly wheel to fit the 99 motor.

 

[Roush380R]

Ok great. It's really that simple? haha. I tried this once before on another car and nothing seemed to work out! So there weren't any real changes in engine specs over 99-04 besides the flywheel deal. I won't have to worry about different compressions, piston sizes, and all that?

Now, I'm not sure how smog technicians do things, but if I am running that ECU from the 2003, it should test and show up on their screens as an 03, right?

thanks

 

[Boostang]

lol yea believe it or not that the only thing majorly changed that will affect the swap.. i mean there are minor things like the cam caps/cam gears/timing cover bolts are different.. but that wont affect the swap by any means.. but yes when the techs hook the computer up it will read 2003

 

[Roush380R]

That sounds great...I'll probably buy the car if it'll be that simple. Thanks boostang for the help.

Anybody else done this before? Any hints, tips, suggestions, warnings before I undertake this project. Thanks all!

 

[Boostang]

no problem yo!

 

[takiller]

That sounds great...I'll probably buy the car if it'll be that simple. Thanks boostang for the help.

Anybody else done this before? Any hints, tips, suggestions, warnings before I undertake this project. Thanks all!

a true friend reps :yes

 

[BakerFX4]

boostang seemed to hit it on the head.

 

[Boostang]

i do waht i can.. ive done plent off engine swaps in many different cars all the way from a cobra motor in my stang too a ls2 in a 3rd gen rx7.. now that was a bitch

 

[Roush380R]

haha i can imagine. Only thing I've done is put an LS6 from a wrecked corvette into a trans am. Other than that, basically only bodywork

 

[Boostang]

View attachment 24503
just a picture of it in my garage!

 

[casper gt]

water pump is also diffrent, not a big problem, but you must use both the water pump & pulley from 1 motor or the other. also switch the intake's as the 99 will have a plastic coolant crossover (if not updated) & the '03 will have an aluminum crossover.

 

[Roush380R]

ok, that shouldnt be any problem, I'll have all those parts on the blown motor that I can change over. So it looks like the only thing I'll have to buy is a flywheel from a 99-00 GT....any other hidden expenses anyone can think of? thanks guys

 

[casper gt]

a flywheel along with the normal b/s for an engine swap (ie. oil, antifreeze, etc.) & you should be set. might wanna throw a clutch in it while your in there though.

 

[Boostang]

no there shouldnt be any other problems that i can think of.. if u do just pm one of us and we'll be glad to hlp u

 

[Roush380R]

awesome...thanks a ton guys. Yeah I was thinking about putting a clutch in...the car only has 30k miles, but to have a blown motor means he probably wasn't driving it too soft. Any suggestions on an after market clutch? I'd like something with a stiff pedal feel but nothing too overboard as the car is mostly stock. Reliability is going to be the key factor here for me. thanks

 

[Boostang]

i use the king cobra in all my cars