So i found out that supposedly my piston ring in my #2 cylinder and my trans is shot so im going all out and swapping out the both of them. I was wondering what modifications are needed to bolt a stock fi 351 to my 91 xr7. thanks
Depending on how long until you have the engine in the car, I might be able to build you an intake that will fit under your stock hood. It's still in the design phase, but things are looking promising. I just need to figure out what I'm going to do about the plenum.
To just bolt in the 351 motor, you need different oil pan and you need a 351 intake manifold. You will also need to modify your exhaust since the 351 is wider. Everything else from the 5.0 should bolt right up to the 351, but its up to you what else you want to change while you are there. I'm in the process of swapping a 393 into my 91 cougar right now, so I'm going through all this stuff myself. I ended up moving the motor back and lowering it a little bit, and buying a set of holley heads for it and one of the typhoon intakes off ebay, and converting the motor to a roller cam, and a whole bunch of other stuff just cause I don't want to get it in there and have to tear it back apart again. Let me know if you have any specific questions while you are doing the swap and I will help you as best I can.
I guess you have a 3" cowl hood----. How much clearance do you have between the hood and the highest point of the elbow. I like the cowl hoods, but like the Mach style just slightly better----just slightly! That is subject to change--daily . I dont think a 1.5" mach would clear and not sure that a 2.5 is even available. Looks to me like they could shorten the elbow a little bit and still clear the fuel rail/injectors. Also wonder if a low rise style would work, similar to what the 4.6's use. Also, is your setup really any lower that a TW upper/lower for a 351? (TW example only). Several questions, hope you dont mind----I like the looks of your setup!
The only way you stand a chance of the intake clearing the stock hood is if you go carb. I know it is possible to make a 351W with a 95 cobra intake clear a 1.5" mach 1 hood, but you need to lower the motor slightly as well as trim out some of the bracing on the hood and then reinforce it. There was a guy in PA who had an 89 cougar who was one of the first, if not the first person, to swap a 351 into an MN12, and that is how he did it. To lower the motor, you can either modify the mounts and then clearance the oil pan so it doesn't hit the K-member, or you could also shim the K-member down. The second option is probably easier, but from a handling point of view that actually raises the cars center of gravity, so if you still want the car to corner nicely, you should take the time to make some custom mounts and beat on your oil pan to make it fit. As for making the custom mounts, the easiest and cheapest way is to just go to the local sporting goods store and buy 4 hockey pucks, then drill holes through the center of them and run a bolt through the lower plate, 2 hockey pucks, and the upper plate and put a nut on top if it. This will be solid enough to not let the motor move any, but the motor will actually be sitting on the rubber pucks so it will help with vibrations unlike a solid mount.
I think I read the guys site that did that one---interesting. Looking at the power elbow, it looks like it could be lowered somewhat closer to the rails on that side. After seeing so much kinda negative feedback on the glass hood issue, I am thinking about getting a cheaper lift-off and cutting the scoop portion out. Then cut and flange (either up or down) the OEM hood to match the scoop and either rivet or epoxy the scoop into the cutout, then glass in the joint. No doubt will stress crack at the joint after a few years, but can be repaired. I have worked with glass a little (on boats) and it really isnt rocket science. That might also help with the latch security problem that some glass hoods have. Anyway, does that sound too crazey to you?
I have a fiberglass cowl hood on my 94 cougar, and I just completely removed the factory latch. I only run the hood pins. Personally, I would never trust any fiberglass hood without hood pins. Even if it came from the factory with a fiberglass hood, I would pin it. For the $20 and couple hours that it takes to install the pins, they are very cheap insurance against a hood lifting. I was trying to look at the guy's site, but he seems to have removed all the info on the cougar. Maybe he sold the car or something. As for installing a scoop on the factory hood, that would be the cheapest method. Like you said, fiberglass is easy to work with and easy to fix when it eventually does crack. I think you can also buy metal scoops and have them welded in. That would cost a little more, but probably less than a fiberglass hood, and that way you wouldn't have to worry about it cracking eventually. Another option is to just cut out some sheetmetal and hack up your hood and make a cowl yourself. That's what I am doing for my 89 cougar. I cut up the hood from a parts car and cut out some side pieces in sheetmetal, and when I get some time to mess around with it, I am going to weld the side pieces in to raise up the center and make a 4" cowl. I figure that should clear just about anything I could ever want to stuff under the hood.
Unfortunately for me, the House Frau has not approved funding for my MIG/TIG. Used to torch weld and have stick welded a little--very little! Kinda want a TIG because of SS and Alum. Also hear that TIG is better for sheet metal----dont know. I may have to dig into the slush fund----but that shoots my dart block in the donkey! Wishful thinking anyway--.
Kinda like the cobra or mach styles or variations of.
A little dreaming here----thats what we do best, isnt it
"hows" come you couldnt cut the elbow at the carb adpt base, clock it a few degrees forward, and angle cut and reweld the elbow so that it is not quite so tall? Appears that there is ~2-3 inches of clearance between the rails (plug wires could go under and front of rail) and the bottom of the elbow. Instead of the TB mount being the highest point, it would be starting back down out at that point. The highest point would be the turn of the elbow. Might hurt flow at higher RPM's, but wont effect mid ranges a whole lot.-----maybe! That might lower the TB and linkage out of the was of the hood a little better. Anyway, .02 more, on the pile
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