Awsme72coupe
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Need some information when swapping my inline 6 for a 302 on my 72 coupe I need to know what I'm in for and what I need to make it happen any help or advice will be appreciated thank you
Engine swap
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If I were in your shoes I would rather swap in a 351C or even a 460!
A 302 is a good motor but hey bigger is better IMO.
Paul
If I were in your shoes I would rather swap in a 351C or even a 460!
A 302 is a good motor but hey bigger is better IMO.
Paul
Awsme72coupe
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I was looking into a 351cleavland I just need to know what changes as far as transmission and engine mounts rear ends stuff like that I have a 302 I just need to know what has to change
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I do not have much exeperience with 6 cyl's, but these Mustangs have mounts on the frame that differ between small block and big block. I am guessing that the six might share frame stands with the small block? You would then only need a pair of engine mounts for a small block (302, 351 etc. use the same engine mount).
Transmissions I think have the same bellhuosing pattern from six to small block, but a trans built for a six will not live behind a V8.
As far as rear ends, anything that left the factory with a 351 cu. in. Or larger engine got a nine inch rear. I would not worry about the rear end until you are making enough power to break the eight inch...
There are many other supporting components that are different as well.
If you six car is nice enough that you want to keep it and not sell it and buy a V8 car, consider buying a parts car that has the V8 driveline that you want in it. It will save you having to search out all the parts individually.
Good luck!
Transmissions I think have the same bellhuosing pattern from six to small block, but a trans built for a six will not live behind a V8.
As far as rear ends, anything that left the factory with a 351 cu. in. Or larger engine got a nine inch rear. I would not worry about the rear end until you are making enough power to break the eight inch...
There are many other supporting components that are different as well.
If you six car is nice enough that you want to keep it and not sell it and buy a V8 car, consider buying a parts car that has the V8 driveline that you want in it. It will save you having to search out all the parts individually.
Good luck!
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Should be a fairly easy swap. What tranny are you running? The 6 cylinder should be same bolt pattern and small block. You will need to buy motor mounts, but the frame mounts should be the same. You should even be able to use some of the front accessories with the right brackets..... power steering pump, alternator. You will need an exhaust of course. But overall should be a pretty straight forward swap.
And if you have a c4 trans behind that 6 cylinder.....don't be scared! I have a c4 that's been abused for years and im pushing 600hp.
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What you will need to do depends a lot on what you want to do with the car after the transplant and what kind of horsepower you want. You may need to replace the radiator, transmission, and rear end. The driveshaft will most likely be the wrong length. You'll need a new exhaust. You'll probably want to upgrade the brakes. As Kevin said, you'll be able to use your existing engine accessories.
Finding a donor car would make the whole process easier.
Finding a donor car would make the whole process easier.
Awsme72coupe
Member
Thank you guys very much in going with a 302 for now I'm going to stick with a 70s street machine look everything on this car will scream 1976 lol I appreciate all your help I'll be sure to keep you guys posted
Awsme72coupe
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I plan on using the same transmission would I still be able to use the same driveshaft
If you use the same tranny, nothing from there back will change. You can use your original driveshaft. That car will have an 8" rear end instead of a 9" It will be just fine behind a 302. If you are not pulling the trans, you wont have to touch anything from there back, leave the driveshaft in the car. What year is the 302?? Make sure you have the correct flexplate. older 302's used 28 oz and newer ones used 50oz if I remember correctly. Also make sure you count the teeth on your old flex plate. They come in either 157 or 164 tooth. You want to make sure the 302 flexplate matches your old 6cylinder one. Your old starter will work if you get the proper flexplate. Let us know if you have any more questions.
Awsme72coupe
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So here is a update I have decided to go with a 302 5.0 H.O. it's comming out of a Lincoln mark 8 I'm getting the whole car so I plan on keeping it fuel injected I'll have the ECU and transmission so I get the overdrive for highway driving what are some of the things I will have to modify in order for this engine to work
Awsme72coupe
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The mark 8 the engine coming out of it is a 1987 model if that helps any
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Engine will bolt in. Transmission crossmember may need to be modified. The OD trans may require floorpan surgery as I think it is larger in the body than a C6.
That's the easy stuff. You will need to integrate the EFI wiring harness into your Mustang's, or I think you can get an aftermarket EECIV wiring harness from Painless. EFI fuel
System operates at a higher pressure, so you will need to change to an EFI fuel pump and lines.
I am sure that I'm leaving something out.
It might actually be easier to go with an aftermarket EFI kit that comes with everything (after swapping on a carburetor style intake manifold) and switch to a Duraspark ignition system.
Going with a more modern EFI engine in a pre-EFI car is a lot more work than doing a carbureted V8 swap...
That's the easy stuff. You will need to integrate the EFI wiring harness into your Mustang's, or I think you can get an aftermarket EECIV wiring harness from Painless. EFI fuel
System operates at a higher pressure, so you will need to change to an EFI fuel pump and lines.
I am sure that I'm leaving something out.
It might actually be easier to go with an aftermarket EFI kit that comes with everything (after swapping on a carburetor style intake manifold) and switch to a Duraspark ignition system.
Going with a more modern EFI engine in a pre-EFI car is a lot more work than doing a carbureted V8 swap...
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save the motor mounts you cant find them for a six very hard to find !!! maybe we can work out a deal if they are good
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I transplanted a fuel injected 302 into my son's Bronco II back in the '90s. It shouldn't be a problem with all of the room under one of our hoods.
Some wiring diagrams will help a lot.
Get all of the harnesses you can, even if you think you won't need them. Hopefully you'll be able to locate the ECU close enough so the harness from the Lincoln will work without having to lengthen it.
You'll need to supply high pressure fuel, look at some of the posts on our forum about retrofitting fuel injection onto our motors, there've been some good discussions about FiTech and Holley Snipers.
The driveshaft length likely won't be correct, so plan on getting a custom driveshaft.
Because the transmission will have overdrive you may want to change your rear end gearing to something lower (numerically higher), which will give you pleasing performance and economy.
All-in-all, it should be mostly straight forward, and you will likely be happy with the results.
Some wiring diagrams will help a lot.
Get all of the harnesses you can, even if you think you won't need them. Hopefully you'll be able to locate the ECU close enough so the harness from the Lincoln will work without having to lengthen it.
You'll need to supply high pressure fuel, look at some of the posts on our forum about retrofitting fuel injection onto our motors, there've been some good discussions about FiTech and Holley Snipers.
The driveshaft length likely won't be correct, so plan on getting a custom driveshaft.
Because the transmission will have overdrive you may want to change your rear end gearing to something lower (numerically higher), which will give you pleasing performance and economy.
All-in-all, it should be mostly straight forward, and you will likely be happy with the results.
Awsme72coupe
Member
Should be a direct bolt in.
Awsme72coupe
Member
Update I just got a 302 engine with a c4 transmission and some of the accessorie brackets it also has motor mounts will I have to change anything on my car can I use the same radiator and my same mounts the engine came out of a 70 mustang if that helps at all
