ran into a few snags on engine swap

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ramair

Well-known member
Joined
May 28, 2011
Messages
134
Reaction score
4
Location
Colorado
My Car
1973 Mustang Coupe 351W
1973 Cougar Convertible(sold)
1966 Mercury Comet 202
1985 F150 4X4
1989 Mercury Cougar XR7
1962 Ford Fairlane
I ran into a few sangs on a engine swap on my 73 Coupe. I had a 302 out of a 78 Granada in the car and over the years I messed with it too many times trying to get it running right. I finally gave up on it and bought a good running 5.8 out of a 97 F250. The first snag I ran into was when I was removing all the FI stuff I broke the front two intake manifold bolts off in the heads, from my understanding this is a common problem with the 5.8 engines. After many hours of drilling, I got them out and retapped the holes. The next problem I ran into was that the intake manifold was too tall. A Edelbrock RPM air gap intake will not fit under a standard hood with a 351W engine, so I used a regular performer intake. The third problem I ran into is the 302 headers do not fit right on the 351W engine. The passengers side goes on easy, but the drivers side is a whole different story. On top of this, both the collector flanges almost contact the bottom of the floors(they are too short). The third problem I ran into is that the power steering pump mount and AC mounts from the 302 will not work on a 351w engine. The 302 alternator mounts work fine but the others don't. So I searched the internet for a PS mount and from my understanding they are rare. I found one on Ebay but it cost a pretty penny,lol. So if you are going to swap out a 302 for a 351w, keep these things in mind when doing it.

 
I ran into a few sangs on a engine swap on my 73 Coupe. I had a 302 out of a 78 Granada in the car and over the years I messed with it too many times trying to get it running right. I finally gave up on it and bought a good running 5.8 out of a 97 F250. The first snag I ran into was when I was removing all the FI stuff I broke the front two intake manifold bolts off in the heads, from my understanding this is a common problem with the 5.8 engines. After many hours of drilling, I got them out and retapped the holes. The next problem I ran into was that the intake manifold was too tall. A Edelbrock RPM air gap intake will not fit under a standard hood with a 351W engine, so I used a regular performer intake. The third problem I ran into is the 302 headers do not fit right on the 351W engine. The passengers side goes on easy, but the drivers side is a whole different story. On top of this, both the collector flanges almost contact the bottom of the floors(they are too short). The third problem I ran into is that the power steering pump mount and AC mounts from the 302 will not work on a 351w engine. The 302 alternator mounts work fine but the others don't. So I searched the internet for a PS mount and from my understanding they are rare. I found one on Ebay but it cost a pretty penny,lol. So if you are going to swap out a 302 for a 351w, keep these things in mind when doing it.
Yeah, it sounds like fun! Thanks for the heads up! I'm doing I6-250 to 302 and pretty much had to buy everything new!

 
You are learning the hard way the differences between the 302 block and 351W block. The 351W is a taller deck, wider block design and while it bolts up to the transmission and motor mounts, everything else is vastly different. The brackets for accessories are different because the block is wider. Look for trucks and mid sized cars in the 70-90's model years for accessory brackets.

Good Luck!

 
I would have never thought that 1" height and 1" width would make that much difference, but it did. I found a power steering bracket on Ebay and bought it, just waiting for it to come in the mail. I also found a set of specific 351W headers at Summit Racing and they are on there way too. The 302 AC mounts are different and it looks like I will have to find them too. I won't mess with the AC stuff right now, I will run the car without it for the time being.

I am also doing a 289 to a 351W swap in my 66 Comet, I have the engine all machined and have almost all my parts to begin the engine assembly. The thing I am now dreading doing on this swap is putting the headers in this car. If it was a automatic it probably wouldn't be too bad, but my car has a four speed manaul trans. The equalizer bar was a tight fit with the 289 and headers, I can wait to see what the 351w will be like. The engine swap on my 73 Mustang gave a me a idea what is now involved in doing these swaps.

 
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