Stupid 4cyl to V8 conversion! [Archive]

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BlazinEagle

11-07-2010, 01:08 PM

If I knew what I know now I would have just bought a damn original V8 car to begin with! AHHHH! After months of building this thing ( I am by NO means a mechanic and really know very little) I am almost ready to fire this thing up.
I did finally finish up switching over all the fuel lines, brake lines, brakes, brake booster, sway bar, rearend and I also installed a tubular k member.
I go to turn the key and the fuel pump wont turn on. I check the switch by the taillight and it was flipped. SO I fix it and go to try again and I get nothing. Check the switch under the drivers seat. It is plugged in so now I am wondering wtf?
I figured out that the wiring of the car is from a 90 GT which I did and the dash wiring is from a 93 4 cyl. There are different relays for the different years and the pins are not in the same location. So I either need to find a 90 GT dash harness or try to wire this damn thing my self!

wildstang89

11-07-2010, 02:02 PM

Should've kept that 90 Gt a little longer before scrapping it. lol Seriously, if you need any help, give me a call.:bigthumb

lxenvy

11-07-2010, 03:30 PM

+1 u need to get either 90 dash harness which is 90 specfic, Or swap everything over to 93. 93 fuel pump relays are not under the seat i think there in the harness. U got a mess buddy but it fixable. And the swaps suck i agree. If i can help or any question pm me. Ill send u my number. Good luck buddy

lxenvy

11-07-2010, 03:33 PM

i have some good write ups on this, and other helpful links. If u need them lmk ill post them!

Goldeneagle

11-07-2010, 03:33 PM

See if this sight helps

http://fordfuelinjection.com/

mwaller5672

11-07-2010, 05:34 PM

Is it the same pain in the ass to go from 5.0 to 2.3.
Mike

Kevin1989

11-07-2010, 05:39 PM

Is it the same pain in the ass to go from 5.0 to 2.3.
Mike

dont think anyone has ever wanted too haha.

BlazinEagle

11-07-2010, 05:50 PM

thanks for the info guys. If I need any help I will let you guys know. First I am going to try to find the correct wiring harness and just put that in. If I cannot do that then I will be calling on my mustang brothers!

mwaller5672

11-07-2010, 06:20 PM

dont think anyone has ever wanted too haha.

Aren't we being funny today : ). Problem is I have everything I need to go to a 2.3 and nothing to go to 5.0. Believe me I would rather have a 5.0.
Mike

Kevin1989

11-07-2010, 06:58 PM

I got ya. Make a nasty 2.3 turbo set up!!!

lxenvy

11-07-2010, 06:59 PM

Is it the same pain in the ass to go from 5.0 to 2.3.
Mike

It has been done just google it! All kinds of write ups:bigthumb

thanks for the info guys. If I need any help I will let you guys know. First I am going to try to find the correct wiring harness and just put that in. If I cannot do that then I will be calling on my mustang brothers!

Well if u have a 93 dash harness grab a 93 engine harness and find out whats up with the fuel pump relays between 90 and 93 u should be good to go!

Its not that bad if u know what to do and get before u start a swap. Big headache when u go in blind. Im there now.

BlazinEagle

11-07-2010, 07:39 PM

Well I have a 90 harness for the entire car in the car now except for the dash. So I think it will be easier to switch dash harnesses than change the car and engine harnesss.

lxenvy

11-07-2010, 07:48 PM

Yes sir, U got it

INSANEBA

11-08-2010, 10:40 PM

I did a conversion some years back on an 86 notch back, but I carb'ed it...

BlazinEagle

11-12-2010, 01:26 AM

Hey is the body harness out of a hatch and a coupe the same length? I know it will not have the hookup for the hatch defrost or light but will it run the length of a hatch car????

lxenvy

11-12-2010, 03:18 AM

Yes, Should be the same lenght!

1baddlx

11-12-2010, 06:58 AM

i did the same setup you are doing and i got frustrated then called a guy and he said check your ground wires well guess what i forgot to hook my ground wire up from the engine to the body,as soon as i did that then it fired right up!

RACEME

11-12-2010, 08:21 AM

You just need to use a test light to see if you are getting the power signal from the computer and also from the power source to the relay under the seat. Here is the diagram. I believe the computer also sends a ground to actually fire the relay.

Stangman

11-12-2010, 10:20 AM

Hey is the body harness out of a hatch and a coupe the same length? I know it will not have the hookup for the hatch defrost or light but will it run the length of a hatch car????

All you would then need is a hatch wiring harness. All the connections are there to plug into.

blue5.8

11-12-2010, 10:56 AM

i have a complete 90 car harness i believe minus the mass air plug u can come look at it and take what u need for 50$

lxenvy

11-12-2010, 01:13 PM

Thats a good deal^^^^. Blue if he passes on that lmk i know a few ppl looking for 90 harnesses

red srides

11-12-2010, 08:47 PM

ther is a bigger black wire by the coil ground it If that dont work the fuel pump relay is under the diver seat put power to it

BlazinEagle

11-12-2010, 08:55 PM

red srides

11-12-2010, 09:03 PM

the only thing diffrent is power options 90 93 car harnes its a lot work to change good luck

lxenvy

11-13-2010, 12:32 AM

Well I just bought a 93 car harness from ebay for $35 shipped so if all goes well then I now have a
93 dash harness
93 body harness
90 Computer A9L
and 90 engine harness
Anyone know if this combo will work?
I have an extra 91 convertible body harness and the 90 body harness extra right now. If I dont use it then I will put it up for sale.

Ur all good with the 93 shit NOW u need a 92 or 93 engine harness. The 93 engine harness has the relays for the fuel pump in it. The 90 has the fuel relays under the seat. U might be able to wire around it best way to find out is get a wiring diagram for a 93 and compare to 90! Good luck