Sanity check re engine swap options/planning

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StPaulSwinger

StPaulSwinger

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Hi all,

very recent owner of a 70 Dart Swinger with a stock slant six/auto tranny (has issues but does crank) and looking to take the opportunity to upgrade to a V8 so I'm doing some research and planning. I'll also be looking to upgrade the brakes (disc up front at a minimum) and suspension.

Generally speaking, looking for an end result that is street drive-able on decent pump gas but improved performance over stock, maybe in the 350-400 HP range if possible. I'm not worried about show car looks or numbers matching etc. Leaning towards a more modern engine but not 100% settled with bonus points for more straightforward projects (I'll have help from people more experienced) as opposed to something requiring a lot of additional modifications above what other swaps would need. I'd like to be around 2-3k if possible though that's not an absolute set in stone number.

I've come across a couple different engine options (on this forum and a few other pages) and I know that there is good support for a 5.9 magnum swap. My understanding is that a Magnum swap requires less modifications than a more modern hemi and that the Magnums have a considerably lower starting price. My first question would be if there are any obvious options I'm missing beyond these two or other considerations I need to immediately take into account before thinking about what engine path to take.

Thanks all, really appreciate any and all advice/thoughts/comments/opinions.
 
I don't think that swapping any modern V8 will come anywheres close to your projected budget. For the kind of money you are looking at you should be thinking about finding a good used engine and transmission to drop in. You will still need V8 radiator, battery?, etc. Factory front disc brakes are a relatively inexpensive upgrade. Good to think about these things ahead of time so you end up with a fun car.
 
With that budget in mind maybe get it running as is & upgrade the brakes.

That way you can enjoy it while looking for deals.
 
I see you are in the BigBlock forum, but are talking Magnum

Additionally you will need a matching trans,rearend,and driveshaft,a V8 K-member or conversion mounts, a complete new exhaust, plus a HD suspension including; V8 springs, T-bars, HD shocks,and possibly some front steering repairs.
Plus V8 cooling system,V8 ignition, and some upgrades to the fuel and wiring systems, with possibly a new fuel tank and lines in your future.
Additionally; gauges
With the go-fast engine, stop-fast brakes are kindof mandatory.
And of course wheels and tires

In order for the Magnum to be peppy, $3000 is a good starting point. To bring the LA into the same arena, with new pistons and heads, it will cost about the same. If your Magnum bores are straight and round, you would be money ahead.
The LA's are a drop-in on the matching K and do not need the electric fuelpump,return line, nor a specialty intake. The Magnum may come with a serpentine belt system which has it's own hurdles to overcome.
 
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My 383 motor at machine shop- restoration rebuild includes roller cam and dyno= $11,000. Welcome to California.
 
AJ/FormS said:
I see you are in the BigBlock forum, but are talking Magnum

Additionally you will need a matching trans,rearend,and driveshaft,a V8 K-member or conversion mounts, a complete new exhaust, plus a HD suspension including; V8 springs, T-bars, HD shocks,and possibly some front steering repairs.
Plus V8 cooling system,V8 ignition, and some upgrades to the fuel and wiring systems, with possibly a new fuel tank and lines in your future.
Additionally; gauges
With the go-fast engine, stop-fast brakes are kindof mandatory.
And of course wheels and tires

In order for the Magnum to be peppy, $3000 is a good starting point. To bring the LA into the same arena, with new pistons and heads, it will cost about the same. If your Magnum bores are straight and round, you would be money ahead.
The LA's are a drop-in on the matching K and do not need the electric fuelpump,return line, nor a specialty intake. he Magnum may come with a serpentine belt system which has it's own hurdles to overcome.
Click to expand...

Thanks, all super helpful!
 
Yeah I did that starting in 1997; A 68 Barracuda from slant 904 to HO 360 4-gear FormulaS clone,etc. Plus a bit of bodywork and a repaint. By the time I was done in 99, I was into it for near $20,000Can, and it still needed seat-covers. And I did all the labor save body and paint, which I got a friend to do, and was in addition to the 20Gs. Plus I already owned the parts car and powertrain.
 
Many swaps can be done with a donor vehicle that you can make money off. We did a 5.2 Magnum swap into an '84 Ramcharger and made money on the deal. Big blocks can be expensive or cheap, depending on what you find (my 440 was basically free as it was in a truck that was left on my property - and I've heard it run, but that was a long time ago). It would probably be a little harder to make money doing a late hemi swap, but if you find the right car and can find a buyer for the leftover parts...
 
About 15 years ago, Mopar Muscle Magazine rebuilt a 340 with stock heads (2.02 intakes), a Comp XE268 cam with matching Comp lifters and springs, Eddy Air Gap, Eddy 750 carb and headers. It hit 392 HP. I built my engine to the same recipe except I used a 750 carb, so I figured I was probably at 375 HP. It is an Awesome setup. That would be perfect for you. You could use a 360 LA, but you'd need decent heads.
 
Really appreciate everyone's input, it's giving me a lot of great insight. I'm out of the country for two weeks shortly so any action will have to wait for a bit but that also gives me time to do more brain work. Obviously I don't want to just jump on the first shiny thing that comes into view and regret it later (even though a 1973 440 and matching tranny just popped up on Craigslist, though I know by that point performance had dropped, at least as it came out of the factory). I also want to make sure I'm doing the brakes justice as well of course.
 
Engine swaps are just like hitting a golf ball 300 yards. Easy if you know how to do it, impossible if you don't.

If you don't know what you're getting into then it will be a big pain and the odds are that you'll eventually give up and sell the car at a huge loss. If you know what you are doing and have the tools, parts and space to do the swap then it is an easy and fun process. For the beginner though, an engine swap can be a nightmare of endless frustration. You'll need to round up a bunch of little parts that are hard to find, especially if you don't know what they are. Lots of stuff has to change and some of the different parts are hard to find. Staying with a factory swap is the best course of action for a beginner since then you can buy stuff like radiators, hoses, belts, throttle brackets, shift linkage, etc. off the shelf.
 
AndyF said:
Engine swaps are just like hitting a golf ball 300 yards. Easy if you know how to do it, impossible if you don't.

If you don't know what you're getting into then it will be a big pain and the odds are that you'll eventually give up and sell the car at a huge loss. If you know what you are doing and have the tools, parts and space to do the swap then it is an easy and fun process. For the beginner though, an engine swap can be a nightmare of endless frustration. You'll need to round up a bunch of little parts that are hard to find, especially if you don't know what they are. Lots of stuff has to change and some of the different parts are hard to find. Staying with a factory swap is the best course of action for a beginner since then you can buy stuff like radiators, hoses, belts, throttle brackets, shift linkage, etc. off the shelf.
Click to expand...
These days, replacement in kind is hard enough to find parts for. I thought the deal with my swap was going to be a breeze when I started, found out not so much. It is by no means impossible like you said though, you just got to know what you're doing. I didn't really know what I was getting into at the time, but anybody spends a few weeks sifting through this forum beforehand can likely get it figured out. Lot of knowledge here.
 
AndyF said:
Engine swaps are just like hitting a golf ball 300 yards. Easy if you know how to do it, impossible if you don't.

If you don't know what you're getting into then it will be a big pain and the odds are that you'll eventually give up and sell the car at a huge loss. If you know what you are doing and have the tools, parts and space to do the swap then it is an easy and fun process. For the beginner though, an engine swap can be a nightmare of endless frustration. You'll need to round up a bunch of little parts that are hard to find, especially if you don't know what they are. Lots of stuff has to change and some of the different parts are hard to find. Staying with a factory swap is the best course of action for a beginner since then you can buy stuff like radiators, hoses, belts, throttle brackets, shift linkage, etc. off the shelf.
Click to expand...
Appreciate the knowledge! I'm lucky to have much more experienced help but they are more in the Ford or import worlds so it's definitely something to keep in mind. I'm not dead set on any one path so any/all advice is more than welcome.
 
AndyF said:
Engine swaps are just like hitting a golf ball 300 yards. Easy if you know how to do it, impossible if you don't.

If you don't know what you're getting into then it will be a big pain and the odds are that you'll eventually give up and sell the car at a huge loss. If you know what you are doing and have the tools, parts and space to do the swap then it is an easy and fun process. For the beginner though, an engine swap can be a nightmare of endless frustration. You'll need to round up a bunch of little parts that are hard to find, especially if you don't know what they are. Lots of stuff has to change and some of the different parts are hard to find. Staying with a factory swap is the best course of action for a beginner since then you can buy stuff like radiators, hoses, belts, throttle brackets, shift linkage, etc. off the shelf.
Click to expand...

Good advice, but I did my first big block swap without enough tools and no internet to help me out and nobody around that I knew who had done the swap, either. I did what research that I could, but in the end I just jumped in and did it. Hit a few snags, but now it's old hat...
 
I did my first engine swap when I was 16 years old. Put a Ford 351C engine in a 1956 F-100 pickup truck. Had to work in the driveway and the only tools I had were a hand me down set from my dad that fit in a fishing tackle box. It took me most of a year but I did get it running and driving. It wasn't pretty but it worked well enough to be my daily driver in high school. Looking back I'd say it wasn't a safe ride, but I didn't know any better at the time. So yeah, it can be done, but the results might not be pretty.
 
Just a quick update, and not sure if this makes anyone's advice/thoughts any different, but the extra transmission I got included in the deal appears to be a 727 torquelite from a 66 Fury. I know that's a very highly thought of tranny so I would assume it makes sense to use that along with pretty much any engine that will match up (as always, please feel free to tell me I'm crazy).
 
727 is a heavy-duty transmission, and it takes a little more power to turn it then it does the 904. Therefore, it makes sense in heavier cars or cars with bigger more powerful engines. Short of that, because it is a desirable transmission you would most likely be money ahead to sell it to somebody who could really use it and build you a 904 with money left over to add to other parts on your project. I'm expecting my build to put out around 420 or so, and still went with a 904 simply because of how light the car is.
 
StPaulSwinger said:
Just a quick update, and not sure if this makes anyone's advice/thoughts any different, but the extra transmission I got included in the deal appears to be a 727 torquelite from a 66 Fury. I know that's a very highly thought of tranny so I would assume it makes sense to use that along with pretty much any engine that will match up (as always, please feel free to tell me I'm crazy).
Click to expand...

Do you know if it is a BB or a SB transmission? If it is a BB transmission then you might be able to sell it and use the money towards your SB engine swap. If it is a SB transmission then perhaps you'll want to use it.
 
StPaulSwinger said:
Hi all,

very recent owner of a 70 Dart Swinger with a stock slant six/auto tranny (has issues but does crank) and looking to take the opportunity to upgrade to a V8 so I'm doing some research and planning. I'll also be looking to upgrade the brakes (disc up front at a minimum) and suspension.

Generally speaking, looking for an end result that is street drive-able on decent pump gas but improved performance over stock, maybe in the 350-400 HP range if possible. I'm not worried about show car looks or numbers matching etc. Leaning towards a more modern engine but not 100% settled with bonus points for more straightforward projects (I'll have help from people more experienced) as opposed to something requiring a lot of additional modifications above what other swaps would need. I'd like to be around 2-3k if possible though that's not an absolute set in stone number.

I've come across a couple different engine options (on this forum and a few other pages) and I know that there is good support for a 5.9 magnum swap. My understanding is that a Magnum swap requires less modifications than a more modern hemi and that the Magnums have a considerably lower starting price. My first question would be if there are any obvious options I'm missing beyond these two or other considerations I need to immediately take into account before thinking about what engine path to take.

Thanks all, really appreciate any and all advice/thoughts/comments/opinions.
Click to expand...
 
Everything you are reading is pretty good info but the one thing not mentioned is the steering.
I installed a street semi in my 67 Barracuda S. Those cars had no power assist equipment which meant no power steering. The big blocks are substantially heavier than the "6". So what ever you do, retain the power steering system. My car is really tough to steer unless you are moving. Parking it is awful. I installed the Hemi in the late 90's and so it is now out of the car getting new rings, bearings, a head and valve job, gaskets, and seals etc. I keep looking at the empty engine compartment and the manual steering box wishing there was room to install a power steering system but there isn't. So I recommend you keep the steering system in mind when adding 300 pounds to the front of your car.
 
AndyF said:
Do you know if it is a BB or a SB transmission? If it is a BB transmission then you might be able to sell it and use the money towards your SB engine swap. If it is a SB transmission then perhaps you'll want to use it.
Click to expand...
Good question, I'll have to research this more now that I'm back in the country. I'll take a closer look and see if I can figure that out.
 
hartsnet said:
Everything you are reading is pretty good info but the one thing not mentioned is the steering.
I installed a street semi in my 67 Barracuda S. Those cars had no power assist equipment which meant no power steering. The big blocks are substantially heavier than the "6". So what ever you do, retain the power steering system. My car is really tough to steer unless you are moving. Parking it is awful. I installed the Hemi in the late 90's and so it is now out of the car getting new rings, bearings, a head and valve job, gaskets, and seals etc. I keep looking at the empty engine compartment and the manual steering box wishing there was room to install a power steering system but there isn't. So I recommend you keep the steering system in mind when adding 300 pounds to the front of your car.
Click to expand...
Great advice, much appreciated.
 
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