[schpiel]

I am new to the world of Mustangs and am hopefully about to start a build. I am not new to working on cars, I just have never had a Mustang. I decided to build one finally after years of wishing I had a fox coupe. I am about to purchase an 89 Lx coupe, originally a 4 cylinder automatic. The car is a rolling chassis. A shop owner I met through work has had many of these body style cars. He actually prefers the Mercury Capris. Anyway, he can order me one of the complete GT40P motors for a crazy good deal, and I have already found a t-5 at another good deal. I am aware of all the mechanical type things I will need to switch over and do, but I am unaware of some of the electrical related things. Which ECU will I need to run the motor? Engine Wiring Harness? I would prefer to retain the fuel injection, all though I have been told that carb is much easier. Keep in mind this is not a project that I need to have done in a month or anything and it is also not a daily driver. That being said I do not have an unlimited budget, so I won't be doing anything too crazy!
Thanks in advance!

[sickfox]

Welcome to MM, Find a donor v8 car?

[schpiel]

Originally Posted by black89GT Welcome to MM, Find a donor v8 car?

This I have thought would make it easiest. So the ECU in the v8 Lx or GT will run that motor? I figured some of the fuel maps would be different? I have alot of background on imports, mainly Hondas, so if I am saying something that is completely stupid with respect to Mustangs, please inform me!

[flyin ryan]

a9l is the mass air 5 speed computer found in 89-93 v8 5sp mustangs and are very common and easy to find. Normal price used range from $80 to $120 but mostly $100 on Web Page Re-director classifieds.

Engine harness is easy to install, don't let that scare you into going carbed. Go carbed for the right reasons not because someone told you fishing a harness throw a hole is tough because it's really not. Harnesses do have differences depending on years but mostly the 90 is the worse to use and requires a bunch of modifications to use in other year cars and 91-93 had airbags etc so to keep things simple and plug and play pickup a used harness from a 89 v8 car off the same website I listed above and it's plug and play from that a9l computer and injector harness and your wiring is done for the motor.

Don't worry about fuel maps and such, it's very common to pull a gt40 or gt40p motor out of an explorer or such and swap the cam and run in a fox mustang. The computer relearns the parameters to a certain extent.

[schpiel]

Flyin Ryan thank you for all of your awesome help! This is the reason I enjoy enthusiast forums like these! I am going to get my transmission tomorrow hopefully and then pickup the coupe next week! I'll start a build thread as soon as I get things going. I work at O'Reilly auto so most of these parts we are discussing I can get through them much cheaper on my discount, such as this ECU you just listed! Again man, thanks for your help!
Sean

[flyin ryan]

no problem and good luck

if that t5 is out of a four cylinder then you'll have to change the pilot bearing to one for a 1984 ranger with the diesel 4-spd.... also one other little thing you'll run into and wouldn't think of or find out til you hit it would be the fuel lines. On a 4 cylinder the fuel lines run up the driver side... on the v8's they run up the passenger side and another is the rear flex brake hose off the 4 cyinder's 7.5" rearend mounts on the passengers side, while the 8.8" rearends mounts on the drivers side. This tends to be a fun process lol so be prepared to bend some brake line and make some braket modifications but it's not too bad.

Also 4cyl cars have different front calipers, spindles, brake hoses, brake hose brakets, and master cylinder so your going to probably want to look to upgrade all of these from a donor 5.0 car or something along the way for optimum braking

Oh and im pretty sure the struts/shocks may be different to but not 100% on that one.

[schpiel]

The t5 I am getting is out of an 89 GT so there should be no problems on that. As far as the brake setup, I am hopefully going to go ahead and do the 5lug swap. The same guy that is able to get me the deal on the motor, can get the sn95 cobra brake setups pretty cheap too, so I should be covered on brakes. Again thanks for all of your knowledgeable advice!