I have a 1976 Cobra II with 56,000 miles. I want to drop in a 351w from a late 80's early 90's F-250. I want to keep the original manual 4 speed in it. What do I need to know? Also, is the car supposed to have a long center consol or a short one?
351w swap
- Thread starter Slate Slamrock
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First thing. A 351w swap is a PITA. (Pain In The A$$). The windsor is wider and taller, making things fit sucks. It can be done and it you have the tools, knowledge and some fabrication skills by all means have at it.
Things to be aware of:
Oil Pan. the II has a special pan to clear the rack for the 302 (it doesn't fit the 351) you will need a front sump pan and "massage" it to clear the rack or go with a manual rack. If you use the stock II bell housing then you will also have to make room for the starter that is in a lower position (more oil pan mods).
Headers/exhaust. There are 2 different engine swap headers out there.
Hooker (cut holes below the brake booster and cut out battery box and relocate battery. Each side the rear 2 tubes snake around from the outside to meet at the c
collector.
Heddman makes a swap header but it is more of a "race header" must use front engine plate, no power steering, all 4 tube on each side meet into a flat wide collector.
The standard 302 Heddman header will work with a LOT of modifications. Or go completely custom and have a set made.
The stock 4 speed transmission is not famous for being very durable. Many have been broke behind the 302 they were installed with. If you are very gentle it will last a little while. If not, get a shovel and a bucket for the parts... plus with the torque of the 351w the 10" clutch won't last long either.
I'm not saying it can't and shouldn't be done I'm just letting you know what you are up against. I did it. I think I would have been happier with a stroker 302 and there would have been a lot less problems. To each his own, good luck which ever way you decide to go. If you have any other questions ask away.
The cars were optioned many different ways. With a short, long or even no console.
Good luck,
Tim
Things to be aware of:
Oil Pan. the II has a special pan to clear the rack for the 302 (it doesn't fit the 351) you will need a front sump pan and "massage" it to clear the rack or go with a manual rack. If you use the stock II bell housing then you will also have to make room for the starter that is in a lower position (more oil pan mods).
Headers/exhaust. There are 2 different engine swap headers out there.
Hooker (cut holes below the brake booster and cut out battery box and relocate battery. Each side the rear 2 tubes snake around from the outside to meet at the c
collector.
Heddman makes a swap header but it is more of a "race header" must use front engine plate, no power steering, all 4 tube on each side meet into a flat wide collector.
The standard 302 Heddman header will work with a LOT of modifications. Or go completely custom and have a set made.
The stock 4 speed transmission is not famous for being very durable. Many have been broke behind the 302 they were installed with. If you are very gentle it will last a little while. If not, get a shovel and a bucket for the parts... plus with the torque of the 351w the 10" clutch won't last long either.
I'm not saying it can't and shouldn't be done I'm just letting you know what you are up against. I did it. I think I would have been happier with a stroker 302 and there would have been a lot less problems. To each his own, good luck which ever way you decide to go. If you have any other questions ask away.
The cars were optioned many different ways. With a short, long or even no console.
Good luck,
Tim
Thank you for all this information. I will definitly consider all of these things before a make a decision. What about the motor mounts? I read in one of these threads that someone used either 2 passenger side mounts or 2 driver side mounts (I couldn't figure out which side they were talking about) and it made everything fit. Do you happen to know where I can find motor mounts? one of mine is broken and if I decide to keep the 302 then i need a new or used one. I do have the transmission that came with the 351. The only thing is that it is an automatic. Is it difficult, if I get a different manual tranny, to line up the 
er hope? I'm asking a lot of questions because I'm working on a very small budget. I have never driven the car because the engine knocks. i replaced to timing chain on it and it workee for a little bit but started knocking again. The chain was incredibly loose the first time. I haven't checked to see if that is the issue again or not. I have to pull the motor out no matter what because that stupid rubber grommet thing that goes between the steering rack shaft and the collumn shaft rotted away. Going back to the engine, I am very hesitant to modify any part of the car because it it very low mileage. 56,000 original miles.
er hope? I'm asking a lot of questions because I'm working on a very small budget. I have never driven the car because the engine knocks. i replaced to timing chain on it and it workee for a little bit but started knocking again. The chain was incredibly loose the first time. I haven't checked to see if that is the issue again or not. I have to pull the motor out no matter what because that stupid rubber grommet thing that goes between the steering rack shaft and the collumn shaft rotted away. Going back to the engine, I am very hesitant to modify any part of the car because it it very low mileage. 56,000 original miles.The motor mounts are a non-issue. The 302 mount bolts right to the 351 and they fit right in. People may have tried to use different mounts to try and "Center" the engine under the hood better. it's offset to the Pass. side a little over an inch. That is to allow room for the steering assy. You would be so far ahead to rebuild your engine. I would suggest a newer 5.0 engine but the balance is different and you wouldn't be able to use your current 5.0 flywheel. The Mustang II flywheel is a smaller wheel than was used with any other V8. That 351 automatic will NOT fit without serious modifications. That isn't a road you really want to go down.
Engine mounts are no longer made fore thre V8. Don't go to any parts store the mount they say is the correct one is not. you have 2 options find a decent used set or a urethane rebuild kit. http://www.sscenterprises.net/4imag...53&sessionid=159a343c1975231c9234729084b699aa These are used by many mustang II onwers out there with great results, myself included. I removed my decent rubber mounts in favor of these.
The engine dosen't have to come out to fix the "rag joint" in the steering shaft. A long extension and a universal will reach the upper bolt and the lower bolt is easy. You might have to unbolt the rack from the subframe but that is only a couple more bolts.
Tim
Engine mounts are no longer made fore thre V8. Don't go to any parts store the mount they say is the correct one is not. you have 2 options find a decent used set or a urethane rebuild kit. http://www.sscenterprises.net/4imag...53&sessionid=159a343c1975231c9234729084b699aa These are used by many mustang II onwers out there with great results, myself included. I removed my decent rubber mounts in favor of these.
The engine dosen't have to come out to fix the "rag joint" in the steering shaft. A long extension and a universal will reach the upper bolt and the lower bolt is easy. You might have to unbolt the rack from the subframe but that is only a couple more bolts.
Tim
