Engine swap? Or engine upgrade?

So me and my father own a 1967 Ford Mustang base coupe with the 200ci inline-6. We want to be able to swap out the engine for a nice V8, but all the extra parts we will need to replace will probably start adding up to more than what the actual car itself is worth. We've also considered keeping the 6-cylinder engine and putting on some upgrades, such as a double barrel carb, new exhaust system, turbo/pro-charger/supercharger, etc. However, we're stumped on what we should do. We could either wait a few years and save up for that V8 engine swap, or start putting money into the stock engine. We honestly don't know what we should do and everything is super confusing. This is the first classic car we have owned and just searching things up on google isn't helping. We've tried looking into rebuilding the original 3-speed auto to handle more power, but we don't know if that'll cost more or less than a brand new transmission (assuming we hire an expert since we're not professionals). We've also looked into finding a donor car, but living in Massachusetts doesn't seem to be giving us many options. We also want to know what other engines can fit inside the car instead of just settling with a period-correct 289 or 302. Maybe a newer 3 valve V8 or a foxbody engine. We don't know what to do. We know what we want, just not what to do to get what we want. I hope we can get some help here.
 
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since you are starting with a 67, you have fewer parts to replace. with the 65-66 cars you have to replace the spindles, starting in 67 you dont as they are the same as the V8 spindles. after that you need to replace engine mounts, chassis mounts, trans, and rear end for the big stuff.

as for what other engines fit, since again you are stating with the 67, most anything in the ford line of engines will fit, including the ohc 4.6l and the coyote 5.0. though these will be a tight fit. so run that built 460 that you punched out to 514+ ci with a matching C6 trans or 4r100w if you want overdrive. just remember to stiffen up the body shell accordingly. and of course dont forget the built 9" rear end for that 600+hp motor.

all that said however, the first thing i would do is seriously think about what you want from this car. daily driver? backup driver? toy? weekend cruiser? show car? race car?

lets say daily driver. i would then hop up the six with a few tricks taken from the pages of fordsix.com or from classicinlines tech page(only pages on that website still active, and there for only technical information), and parts available from vintageinlines.com. with the right combination of parts you can ke anough power to keep up with todays traffic, surprise some V8 powered cars, and others, and still turn in 25+mpg.

heck if you dont want the small six, but dont really want to swap a V8 in, then swap in a 300ci inline six from a pick up, and build that. those engines are also very capable for good power output, and do in fact fit the mustang engine compartment. wont get that 25mpg, but 17 should be doable.
 
since you are starting with a 67, you have fewer parts to replace. with the 65-66 cars you have to replace the spindles, starting in 67 you dont as they are the same as the V8 spindles. after that you need to replace engine mounts, chassis mounts, trans, and rear end for the big stuff.

as for what other engines fit, since again you are stating with the 67, most anything in the ford line of engines will fit, including the ohc 4.6l and the coyote 5.0. though these will be a tight fit. so run that built 460 that you punched out to 514+ ci with a matching C6 trans or 4r100w if you want overdrive. just remember to stiffen up the body shell accordingly. and of course dont forget the built 9" rear end for that 600+hp motor.

all that said however, the first thing i would do is seriously think about what you want from this car. daily driver? backup driver? toy? weekend cruiser? show car? race car?

lets say daily driver. i would then hop up the six with a few tricks taken from the pages of fordsix.com or from classicinlines tech page(only pages on that website still active, and there for only technical information), and parts available from vintageinlines.com. with the right combination of parts you can ke anough power to keep up with todays traffic, surprise some V8 powered cars, and others, and still turn in 25+mpg.

heck if you dont want the small six, but dont really want to swap a V8 in, then swap in a 300ci inline six from a pick up, and build that. those engines are also very capable for good power output, and do in fact fit the mustang engine compartment. wont get that 25mpg, but 17 should be doable.
Thanks for you response. As for what we’re using our Mustang for, it’s a daily driver/toy/weekend cruiser. We bought the car because we wanted something to work on and have fun with. Hopping up the six could be fun, but we still would like it if the car would screw. I’ve read that the 200ci inline-6 can handle up to 250 horsepower. Me and my dad have been looking for options ever since we had gotten the car. My dad is cool with attaching some parts to the six, but knowing him he’d probably love to swap in a V8.

For a V8 swap, what would we have to replace? I know we’d need to replace the brakes, rear end, and what you’ve listed. I would like to know everything we’d have to do so I can find prices and see what will work for us.

We both understand that hopping up the six and swapping the V8 will cost a lot of money, but we just want to know how much it’ll cost and how happy it’ll make us. Google hasn’t been giving us straight answers as I’ve stated before, so I’d appreciate it if I could get another reply. Thanks.
 
cost is kind of relative at this point. how much is very hard to say because of so many variables. there was a time when making 500hp from a big block would cost you about 500-1000 dollars. not these days though. too many variables to list, things like labor rates, parts cost, how muc work you can do yourself, how much work needs to be farmed out, what condition is everything in, etc. etc. etc.

as for how much power a small six can make, the limiting factor is the cylinder head, and vintageinlines has the answer in the form of an aluminum aftermarket head that has already taken an early falcon into the high tens(turbocharged 250ci), and has made 323hp on the dyno in street form. the problem is that the whole package runs something on the order of $2500, low production unfortunately. also they are not always available, since he needs to do a run of 100, i think, to get the best price for the low volume, so he waits until he has enough people wanting the heads before making a run.

as to how happy either set up will make you, again that depends on many factors.

the best thing to do is sit down and make a plan. decide exactly what you want from the car in general terms. what would you be happy with for this car. then start making plans for how to make that happen within your budget. and when setting a budget, take what you think it will cost to build this car like you want, and double it.

as to what parts to replace, again that depends on what your plans are for this build.
 
I agree with the above. Figure out what you want from the car.

My first car was a 67 6cyl coupe that my mom gave me. I still have it. The only difference besides color, is that mine is a 3spd and it is power nothing. Yours looks loaded, with AC, AT, PS, and PB. Growing up in the mid 80's, I was always tempted to V8 swap it. As I realized going to car shows, there were not many 6cyl's around. I decided to keep it a 6 cyl. I modified the suspension to make it handle better, added wheels and tires and drove it. While it is not fast as a v8, it is an awesome cruiser. It will cruise down the freeway with no problems. Ultimately, that is what I decided I wanted. I have other V8's cars to fill my V8 need. Good Luck to you guys
 
As pointed out already the question you are asking can only really be answered by you. A few things to consider though. I take it this is a project that you and your dad are wanting to work on together. What is your skill level and comfort level. Can you fabricate? If so to what degree. Are you competent enough to make your own engine mounts and cut out the shock towers for a better front end setup? For me personally the answer to both of those questions is no. The point I'm getting to is to take into account what you THINK you can do vs what you will have to pay someone else to do.

The car you are starting with can be adapted to house any number of engine options. If you want to keep it simple. Id suggest limiting the engine options to simple carbureted stuff. That way you dont have to deal with EFI and the wiring and sensors that come along with it. That rules out most of the modern stuff. That still leaves you with tons of options! 200, 250, 300, 289, 302, 351, 390, 428, 460. All kinds of stroker options. All with carburetors.

Sit down with your dad and really think about what you guys want to spend and where you want to be at the end of the build. Oh and timeline. You can do it fast and expensive or slow and cheap(cheaper). Once you have that lined out come back here and tell us what you are working with. At that point we can stop speculating and really give you some advice to reach you goals. Good Luck!
 
Start with the most basic question:

What is the goal of this build? Don't worry about picking an engine until you decide what you want the car to do. Do you want it to be a reliable cruiser for weekend shows? Do you you want it to be drag-strip terror? Do you want it to tear up the the Auto-X track? Do you want it to be a daily driver? Once you can answer that question, you can decide on the appropriate engine...but certainly don't spend any money until you have a goal and a plan to get there.
 
I would stay with the I6 then. Very reliable engines(I6s are the most reliable internal combustion engine by design). If you want a bit more pep, simply do a few mild upgrades...a T5 swap as an example will make it much more fun to drive....it will also get you close to 30MPG fuel mileage.
 
I would stay with the I6 then. Very reliable engines(I6s are the most reliable internal combustion engine by design). If you want a bit more pep, simply do a few mild upgrades...a T5 swap as an example will make it much more fun to drive....it will also get you close to 30MPG fuel mileage.
Me and my father have settled on trying to keep it automatic if we were to get a new transmission. Maybe something with 4 gears and overdrive.
 
Me and my father have settled on trying to keep it automatic if we were to get a new transmission. Maybe something with 4 gears and overdrive.

if you stick with the six, you will have to adapt a four speed auto as there isnt one that bolts to the six cylinder block. there have been people that have adaptefd the C3 bell from an inline six to a four speed auto from a ranger or explorer, or a four cylinder fox body mustang.