Swap 94 cobra motor to 89 fox?

[mustang88_cars]

I have the oppurtunity to buy a cobra motor from 1994 cobra. It has 100,000 mile on it. He is asking 1,000 dollars for it. My 1989 5.0 GT has a spun bearing. My two questions are, is it worth the money, and can I easily place in my fox body car. If so what will I need to do. I would greatly appreciate any help, I really want my car back in good shape and I want to start running in autocross. Now one can seem to tell me if I can even do the swap. Thanks

[portponies]

I basically have the same set-up in my '89 Saleen. It's a direct bolt in.

I used my stock block, bored it .030 over, installed an Anderson B2 cam, '94 Cobra heads with the 1.7 rockers, Cobra upper & lower intake, 65mm tb, 70mm MAF, 24lb injectors, and FMS headers. This combo dyno'ed 238 rwhp and is a blast to drive at Road America.

The next and probably last item to change are the gears. It currently has the 3.08's in it and those will give up thier space for a nice set of 3.73's.

[Greg@GLD]

Welcome to MMA...!

$1000 for a 10 year old motor with 100,000 miles is not really the way I'd do things. For that kind of dough you can find a decent motor. Plus consider that while that Cobra motor has decent GT40 iron heads on it, the shortblock itself has weak pistons. The pistons in your '89 are forged. If it were me I'd have the crank re-ground and repair the spun bearing...
With that saidm if you do decide to opt for the Cobra motor, this is an easy swap. You will want to transfer the timing cover and water punp from your old motor to the cobra block as well as the oil pan. You will need to do something about the upper intake as the '94 style has no provission for your fox body style EGR. If you can find a used GT40 intake or fox style Cobra intake that should work well.

The GT40 iron heads are what make that Cobra motor worth anything. Perhaps you could sell the intake set (you could get a pretty good chunk of change for the 94-95 Cobra intakes)

[Greg@GLD]

I basically have the same set-up in my '89 Saleen. It's a direct bolt in.

I used my stock block, bored it .030 over, installed an Anderson B2 cam, '94 Cobra heads with the 1.7 rockers, Cobra upper & lower intake, 65mm tb, 70mm MAF, 24lb injectors, and FMS headers. This combo dyno'ed 238 rwhp and is a blast to drive at Road America.

The next and probably last item to change are the gears. It currently has the 3.08's in it and those will give up thier space for a nice set of 3.73's.


Remember though, you used your Fox style timing cover and water pump and oil pan, these things are all different between SN95 5.0's and foxes. If he tried to bolt that motor in right out of the cobra, he would have some issues with the accessories not lining up, and the intake set would be useless as well...

[portponies]

Remember though, you used your Fox style timing cover and water pump and oil pan, these things are all different between SN95 5.0's and foxes. If he tried to bolt that motor in right out of the cobra, he would have some issues with the accessories not lining up, and the intake set would be useless as well...

True, very true. You might just be better off taking that $1000 and applying it towards a rebuild with upgrades.

I read a lot of articles and talked to a lot of people before I rebuilt mine. That way I had a pretty sure goal in mind for what I expected out of our car.

It also helped that I got some really good deals on some good used parts (i.e. cam & heads).

[Greg@GLD]

It also helped that I got some really good deals on some good used parts (i.e. cam & heads).


:cool: :thumbs_up

[Nick 1]

I sold a 95 Cobra shortblock 2 years ago with 30,000 miles on it for $600.00.
You could still see the crosshatch in the cylinders !!!!! That is too much cash for a 100,000 mile motor.

Nick 1

[quietflow]

Too rich for my blood, I say rebuild!

[Kool Rock Steady]

100k is a lot of $ for that motor. Heads should get a v.j. new springs ect. hyper-crap pistons ect. ect. You would also need to change the water pump too if I remember correctly...

[Greg@GLD]

100k is a lot of $ for that motor. Heads should get a v.j. new springs ect. hyper-crap pistons ect. ect. You would also need to change the water pump too if I remember correctly...


The water pump AND the timing cover. You can't use a 1994-95 timing cover on a fox application, the water pump does not bolt to it. It is recessed for clearance. The pump and cover are application-specific...