Do I need any parts? 2.3L to 5.0L

DarkFireGT

Playing with my wife's really makes me want one.
10 Year Member
May 23, 2004
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East Moline, IL
Found a great donor for my '77 Cobra II with a 2.3L. It's a '76 with a modified 5.0.. Everything's there and it's a great car. Got a hell of a deal on it. The motor alone is worth more than I got the whole car for. So now I'm finally going to get my II the way I want it.

So what, if any, parts do I need? Or is it just a swap of all the parts...? Engine/trans/driveshaft/axles/exhaust...
 
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Found a great donor for my '77 Cobra II with a 2.3L. It's a '76 with a modified 5.0.. Everything's there and it's a great car. Got a hell of a deal on it. The motor alone is worth more than I got the whole car for. So now I'm finally going to get my II the way I want it.

So what, if any, parts do I need? Or is it just a swap of all the parts...? Engine/trans/driveshaft/axles/exhaust...
Its your car, but a 4cylinder Cobra is probably one of the rarest CobraII's.
 
I hear you. And I've fought that for the 4.5 years that I've owned the car. But in the 4.5 years, I've only driven it once. I never bothered to go get the bonded title for it so I can license it. It turns over but won't run anymore. The probably needs a rebuild (at a minimum, the carb does), and I guess I'm just not that excited to spend all that money on it.

On top of that, my wife got rid of her Mustang, so now we only have mine and she's really missing hers.. but she's like me.. she's gotta have the V8.

On the other hand, I found a 76 with a 5.0L that was rebuilt 4 years ago, has a high rise cam, aftermarket carb, full exhaust, 4.11 rear end, and slap shift tranny. It sounds amazing and I stole the entire car from the guy for $600 because he's being deployed.

If anyone were willing to pay me what I've got in it, I'd happily send it off to them and get a different toy. But between the $1500 I spent to buy it, and the few grand it cost to get it back home, nobody wants to make me the right offer for it. I'd love to see it preserved, too. But it's not any fun if it just sits.

AND, it's missing the buck tag, so there's no real way to tell it truly was a Cobra II, and that the college girl who owned it didn't just have her daddy buy the Cobra II stuff 'cuz she wanted her little 4 cylinder to look like the car from Charlie's Angels.
 
Thanks for the heads up. I'll check that out.

*edit* I went ahead and ordered the deluxe report with the email option, so I should have my report in about 4 business days. We'll see what she really was soon enough.
 
Ok. Definitely will do.

Got my donor to my garage today. Man, this engine and trans is strong! Dropped it to 1st at 40 and didn't hesitate. I'm sure my neighbors are going to love it LOL!

Let the build begin!
 
Yes, your donor should have everything you need. The good thing about this swap is that there are no major assemblies like a suspension cradle that need changed. You'll want to change the springs, but that can be done after the car is running.

So what is the donor car...coupe or hatchback? What kind of condition? Much rust?
 
It's pretty rusty, particularly the inner fender wells. But everything I need is in good condition and has only been there about 4 years. It's a coupe. Thanks for affirming my thoughts on the parts needed. I'll start a build thread soon.
 
Did the donor come from the factory with V8? If so and barring broke mounts you should be OK. If the car wasn't a factory V8 it could have been cobbled together in which case there is no telling what you may need.

I think you'll find the I4 harness/loom is different than the 8's harness.

IIRC your Cobra is close to if not factory so you may want to swap the wiring and preserve the I4's loom.
 
I'm pretty sure it was a factory V8. Yes the Cobra is all stock. I will most likely pull the I4 wiring out (save it) and duplicate the V8's wiring. The wiring on the donor is dingy and I want it to look nice. But it looks fairly simple.
 
Neat thing is, damned near every wire between the cockpit and engine bay can be removed by a single connector at the firewall.

You need to remove and inspect this connector anyway. Over the decades the plug tends to corrode and cause problems. A DMM will return voltage but the connection may not pass amperage.

If you could do Me/Us/Yourself a favor, WITH the I4, after dropping the drive shaft and before pulling the engine / trans, measure the center of the trans output from left/right to a structural member (sub frame rails, reproducible spot in the tunnel) and center to bottom of the tunnel, AND the engines inclination in relation to a structural member (front frame rails or center of rocker panels).

If after you swap the engine and trans and then have or develop a vibration these are the first two things to check, all else being equal.

For me to gather this data I would need to reinstall/ stick the V6 back in. It wouldn't take long or be difficult but but it's extra work for something I forgot to do before pulling the engine. :(
 
Thanks for the heads up, Wart. I think I can remember to get those measurements for you.

Here's a few pics of the donor, including the mounts. They look stock, but I've never looked at a known factory 5.0L one to compare it to. And yes, the rust is gonna make this fun I'm sure.

IMG_5196.jpg


IMG_5197.jpg


IMG_5230.jpg


IMG_5222.jpg
 
So I got my Marti report today, finally. I had to email them and then I got it right away, so they must've forgot about me. Anyway. Results are in......



drumroll......



Car was really a 4 Cylinder Cobra II. Crap. Now this is a tougher decision LOL.
 
Not a hard decision. Do what makes you enjoy the car the most.

As unusual as a 2.3L CBII is, if you don't enjoy driving it, eventually you will sell it or give up on it. And don't forget, at this point, ANY MII on the road is unusual.

The good thing about a 302 swap on a MII is that it is completely reversable. Just save as many of the original 2.3L parts as you can.

Use the wiring from the V8 donor. It can be cleaned up. Several companies sell the materials to make it look new again. It will take several days of careful work though.

Get those headers sandblasted and have them ceramic coated, replace that water pump with an aluminum one.

Take lots of pictures and share!
 
One other thing I didn't notice anyone touch on is the rear Diff. The 4 cyl cars usually ( I say "usually" because FORD had at least one exception to every rule) had a 6.75 in integral carrier rear. The v6 usually (that same word again) and V8's had the stronger 8" rear that your donor has. Most likely the 4cyl rear will not live a nice long life behind that 302.

Tim
 
One other thing I didn't notice anyone touch on is the rear Diff. The 4 cyl cars usually ( I say "usually" because FORD had at least one exception to every rule) had a 6.75 in integral carrier rear. The v6 usually (that same word again) and V8's had the stronger 8" rear that your donor has. Most likely the 4cyl rear will not live a nice long life behind that 302.

Tim
The rear in the donor car has been built, so I plan on swapping that as well. The entire driveline and steering rack is going to be swapped, so engine, trans, driveshaft, rear end, rear suspension, exhaust, etc... will all be going into the Cobra II.