I recently found your page on mustangs and was wondering if you guys could help me out with my little project. I have a 97 Mustang GT Convertible, and my engine gave out on me with piston compressions all over the place. I have found and decided that I want to install a 96 Cobra motor into my car. I know that it will fit, with the factory engine computer and wiring in place, but have not found any information about it being compatible with my automatic transmission. I assume so, since it will be running off of my factory engine computer, will modify my chip and get a tune of course, but I just wanted to make sure that it will actually line up and such. Everything is coming together, and the install seems fairly simple, any input or suggestions would be greatly appreciated. Thanks in advance.

 

well ur going have to move stuff around on the harness { extend wires of sensors} , your going to need a 8 bolt felx plate from ford racing. you are going to need a tune, cobra motors come with bigger injectors, u need a imrc delete. but as far as its going to be on a auto , as long as u use ur stock ecu and harness there is no issues.

 

^^^^ knows his modular stuff....I'm a modular idiot

 

He can use the flex plate from an automatic Mach1 or Marauder.

The stock GT computer will run everything just fine. It will need the shift points adjusted because the 4v will be a little less torqy down low then the 2v was. But should work just fine. When I did my 2v to 4v swap I used the GT computer first because I wanted to see how it was and if there was any difference from the Cobra computer. Ran just fine with the GT computer even untuned. I then swapped to the Cobra computer and noticed a little bit cleaner low to mid range pull. 2500 - 3500 r pms. I used both,.. the GT MAF and the Cobra MAF. I assumed with the 24lb injectors with cobra MAF was calibrated for them,.. but seems even with a GT computer and MAF,.. it doesnt matter if the engine has 19lb or 24lb injectors,.. the MAF voltage signals are the same in the SN95 cars. Using the Cobra computer with the Cobra MAF made it a little cleaner than using the GT MAF with the Cobra computer.

And ditto for the IMRC's. The only way to get the IMRC's functional will be to do a complete wiring harness swap. The GT fuse block does have a provision for IMRC's,. and I did originally install the Cobra engine with the Cobra engine harness mated to the GT computer/dash wiring harness. But the pin outs from the Cobra to the GT are completely backwards and dont match up. You would think that a 96 GT to 96 Cobra that the wiring would be similar. I found out the hard way,. they are not. The Cobra harness has an extra coupling for the O2's to preheat that the GT harness does not have among other problems. The best way to deal with the IMRC's is to pull the intake off and do an IMRC delete to the stock plates. Just pull the rods out, remove the plates, use an epoxy like JB weld to seal the holes where the rods went through. You guys can laugh,. but it works. The other options would be to buy ready made IMRC delete plates ($175 - $200) or clip the cables and lock them to the wide open position (red neck).

Having done a couple 2v to 4v swaps I went into the first one expecting one thing and learned enough to know how to make the second swap much much easier. Just use the GT wiring harnesses and it will make things so much less complicated.

Hurst

 

lol jim i took the spring off the imrc and took bailing wire and warped it so they where open all the time. and you know how u found out the cobra harness did work , i found out 96/97 has 4 different harnesses for GT's 5 speed cars { the hard way}

 

That would drive me nuts. I didnt know they are different even among the GT's. Thats one of the things with Fords that I never liked. They tend to complicate things when it comes to mixing and matching parts. At least with a GM small block is a small block,.. and even among big blocks, LT1's and LS motors,.. GM still kept as much that could interchange possible. Ford likes to change things up from year to year and as we have found out,.. even within the same year.

I mean 2v heads. Windsor and Romeo.. they are the same identical head design. Just one uses 13 bolt for the valve over and the other 11. Who's bright idea was that? Then for the T45 transmissions. The Cobra spec has the mount location at the end of the tail shaft and the GT is closer to the case. Again,.. why? For what purpose does the extra tooling costs justify the differences?

You have to almost be autistic to remember what goes with what sometimes.

Hurst