1995 supra Sunsport engine swap

[miller]

Hey guys I'm new here. I have searched and haven't found anything yet. I have a cracked block on my pro boss. I just bought a ford 351 Windsor to replace the old motor. It is a rebuilt motor a little over a year ago coming out of 65 mustang. Can anyone make suggestions I need to do to it to make it a marine engine. I will be using most of all my old parts from the original motor. Thanks

[chris young]

I'm not a motor guy, but I do know the cam for that motor will not be the right one. I'm sure it'll work, but I know the marine version is not the same. As I understand it the marine version is set up for a lot more bottom end torque, so I'm guessing your hole shot will be a bit weak. There are some really good motor guys on the forum so they can chime in on anything else to watch for. Since you're moving everything over from the old motor, I don't see a problem otherwise. For safety you must use the starter, alternator, distributor and carb off the old motor for sure. And fuel lines should not be rubber.

[Moor]

i'm not a ford guy, but i know some of the older chevy cylinder heads do not have the mounting locations for the marine accessory brackets. Double check your heads to make sure you can bolt all of your brackets onto the old mustang motor/cylinder heads. Also verify that the exhaust manifolds have the same bolt pattern and are compatible. Chris is correct, the camshaft will not be optimized for marine use, but should work. Depending on what intake manifold you have, it may be the same case as the camshaft.

I'd verify the donor motor is good with a compression test and leak down test before i even considered it. Just because it was rebuilt a year ago, doesn't mean its a healthy engine. A lot can happen in a year, and "rebuilt" can mean a lot of different things to different people. Why is the mustang owner getting rid of an engine he just rebuilt last year?

[miller]

alright thank you both. I had my mechanic check out the motor before I purchased it. Everything seemed to check out. He was selling it because It was too big for the engine bay and power steering would not fit. It originally came out of a crown Victoria. I will check out the brackets and exhaust manifold bolt pattern.

Again thank you. I will post some pictures and updates for anyone interested in following the progress.

[Cusefan78]

So your Proboss and the 351 are both fords and are the same block. The difference is the marine engines were set up more like the trucks versions. You're going to use the gt40 heads off the Proboss engine. You'll add a bunch of horsepower. Also all the freeze plugs will have to be switched to the brass ones. Last thing to check is to make sure the Proboss wasn't a reverse rotation motor. If it is, You're going to make to switch the prop. Keep us posted. I love these threads.

[SquamInboards]

So your Proboss and the 351 are both fords and are the same block. The difference is the marine engines were set up more like the trucks versions. You're going to use the gt40 heads off the Proboss engine. You'll add a bunch of horsepower. Also all the freeze plugs will have to be switched to the brass ones. Last thing to check is to make sure the Proboss wasn't a reverse rotation motor. If it is, You're going to make to switch the prop. Keep us posted. I love these threads.

Good point on the rotation. This boat would have a 1.23:1 transmission, right? I believe you would have to also switch something on the transmission if you had to switch the direction it's being spun. My memory is a bit hazy and I'm at work so I can't spend a lot of time googling it, but that was my recollection. (Front main seal??) If they're the same rotation, there's no problem obviously. But you may still want to check WOT RPM and consider a new prop regardless. Any change in power might make a prop swap a good idea.

[lively]

Look for some different valve covers , cause I don't think the aluminum ones you have will work with the manifolds


Sent from my iPhone using Tapatalk

[miller]

Alright guys, I got the old engine pulled yesterday. Lucked out by a granite shop my brother worked for letting me used their shop crane. Made it simple. Had 6 bolts loosened. Took all of 1 hr to back the boat in. Hoisting the engine. And dropping it into the truck bed. Now time to start swapping parts in the garage and removing those stubborn bolts in the manifolds how y'all suggested. image.jpg
image.jpg

[lively]

Soak the bolts in some rust penetrant , tap the head with a dead blow hammer and a punch , tighten first then loosen , then tight then try to back it out . Heat it up if all else fails


Sent from my iPhone using Tapatalk

[miller]

Here's another update. Still a no go on the manifold bolts. I have tried all of your suggestions. Thank you. I did manage to extract one. I think I will end up drills mg them out.

As for rotation. The old motor has a 1:1 percent tranny. Research tells me it's a clockwise rotation engine along with the new engine. Should all pair up.. Hopefully.

I ended up having to swap more than I thought including the water pump, the timing chain cover, the oil pan, distributor, valve covers. Pulleys, oil pump screen, and all the gaskets that go
Along with that. So that's where I am today. I received the wr My gasket for the timing chain can get unless that would all be back and installed. While the parts were off. I cleaned everything in engine degreaser and Clr. Added some paint and poof. Blue and yellow theme.

image.jpg

image.jpg