55.2-59 What’s the most practical way to swap engines?

[MiraclePieCo]

Originally Posted by washington blue

A carburetor engine needs to run above 2000 rpm to work well.

Huh?

[washington blue]

A carburetor engine needs vacuum and mechanical advance to run it's best. Full Mechanical is at about 23-2600 rpm and full vacuum is at about 2000 rpm. Running the engine down the road slower than say 2300 rpm is not good for gas mileage and not good for the engine either. The reason to put an overdrive transmission in something is to get better mileage and less engine wear. Very hard to do with an overdrive trans hooked to a carburetor engine. The OP said he likes carburetors and he wants to keep the original suspension and he plans to drive around town and occasionally a few miles out of town. With this info a 700r4 would not be the best trans for him. Buy something like a 1975 Nova 4 door in nice shape and take the 350 engine and Quadrajet carb, th350transmission, driveshaft, and rear-end out of it and put them in the 56. Very straight forward simple swap. This way you have exhaust you might use and E brake cables and
lots of other little stuff too.

[mick53]

I've seen head to head tests (Engine Masters / Motor Trend) and the carb did just as well as injection. Injection is much easier to tune. A crank fired ignition will benefit any engine for tuning advance curve. I'll be running 3 Roch 2 bbl's progressive linkage, crank fired ignition and a 4-71 blower on my 292. Gaerte Racing Engines tells me it will do just fine. They also said it was going to be a pain in the a#* to tune to start with. I think the carb's look a lot cooler.

[dsraven]

all the previous stuff aside.
first, decide what your budget will be.
second, decide what you want to end up with
third, be truthfull with yourself (and your partner if there is one). do a complete and thorough check over of what you have and what it needs. do some legitimate pricing on the parts you will need and any labour you can't do yourself.
fourth, decide if this is something you want to invest in or can afford to invest in. is it gonna cause trouble in the household when time and money are spent on "that old wreck".
start with the underpinnings, get a good base to put everything else on top of. if the body is in good shape then thats great. you can drive it around with a couple of bad cab corners but driving with worn out suspension and brakes could be disaster. start with the base and build off of that.the problem here is that you really should take the body off the truck so you can ensure the frame is really in as good a shape as what you think. do some checks to ensure it is square, straight and doesn't sag. check the crossmembers for loose rivets, cracks, rust between the mounts and frame etc. it's not a bad idea to dissassemble the entire thing and have it blasted so you know exactly what you have before you start. the area around the front shock mounts, for example, can rust badly over time and be almost through the frame thickness if you remove the bracket and blast the area till you see good clean steel. the same goes for the rear suspension mounts. anyway, all I am saying is do a thorough checkover of the most important part of any vehicle-the part that supports the suspension, body, and driveline-the frame.
check the entire truck and make a list as you go. be truthfull and don't skip over anything. price out the parts to fix it the old way and then price out the parts to fix it like you want to end up. sometimes the cost to repair the old will go a long way towards replacing the old with the new design that you want in the end. when you say it will be short trips around town, that, to me, says ifs and p/s, p/b. highway driving isn't so bad with a straight axle, not really any short turns to worry about and not really any quick stops in stop and go traffic.to me, ifs would be more of a "must have" for city driving. for long trips a solid axle would be ok (but I would still WANT ifs,lol).
if you find the front end and suspension are ok to drive as is, then the other option is to drive it that way while you fab a whole complete new frame with the suspension you want. then,when complete, swap your body and driveline over.
if it is simple you want for a driveline choice, and city driving is all you will be doing mostly, then a good running carbed 350 with a turbo 350 behind and a good rear axle ratio will be all you need. if you find things change and road trips are more your style you can always swap in a 700r4 later. if you want to upgrade to fuel injection then install a good running LS engine and get the computer remapped for your design, gear ratio, exhaust etc. the LS, in my opinion, is the new small block chevy. sorta like the old days when everybody was swapping in the small block where the old inline 6 used to live.
thats just me though. if you love the small block then do what you want, it's your hotrod. electronic engines will also need some sort of speedo revamp because there is no speedo cable adapter in the trans. more money to account for
in the end do a check of what you really have and what needs you have, then do a study to back up your plan. then look at it like someone from the outside would and decide, logically and budget wise, what your plan will be.
most importantly---take pics and post them as you go.

[washington blue]

dsraven, well said.

[Phungki]

Originally Posted by dsraven

all the previous stuff aside.
first, decide what your budget will be.
second, decide what you want to end up with
third, be truthfull with yourself (and your partner if there is one). do a complete and thorough check over of what you have and what it needs. do some legitimate pricing on the parts you will need and any labour you can't do yourself.
fourth, decide if this is something you want to invest in or can afford to invest in. is it gonna cause trouble in the household when time and money are spent on "that old wreck".
start with the underpinnings, get a good base to put everything else on top of. if the body is in good shape then thats great. you can drive it around with a couple of bad cab corners but driving with worn out suspension and brakes could be disaster. start with the base and build off of that.the problem here is that you really should take the body off the truck so you can ensure the frame is really in as good a shape as what you think. do some checks to ensure it is square, straight and doesn't sag. check the crossmembers for loose rivets, cracks, rust between the mounts and frame etc. it's not a bad idea to dissassemble the entire thing and have it blasted so you know exactly what you have before you start. the area around the front shock mounts, for example, can rust badly over time and be almost through the frame thickness if you remove the bracket and blast the area till you see good clean steel. the same goes for the rear suspension mounts. anyway, all I am saying is do a thorough checkover of the most important part of any vehicle-the part that supports the suspension, body, and driveline-the frame.
check the entire truck and make a list as you go. be truthfull and don't skip over anything. price out the parts to fix it the old way and then price out the parts to fix it like you want to end up. sometimes the cost to repair the old will go a long way towards replacing the old with the new design that you want in the end. when you say it will be short trips around town, that, to me, says ifs and p/s, p/b. highway driving isn't so bad with a straight axle, not really any short turns to worry about and not really any quick stops in stop and go traffic.to me, ifs would be more of a "must have" for city driving. for long trips a solid axle would be ok (but I would still WANT ifs,lol).
if you find the front end and suspension are ok to drive as is, then the other option is to drive it that way while you fab a whole complete new frame with the suspension you want. then,when complete, swap your body and driveline over.
if it is simple you want for a driveline choice, and city driving is all you will be doing mostly, then a good running carbed 350 with a turbo 350 behind and a good rear axle ratio will be all you need. if you find things change and road trips are more your style you can always swap in a 700r4 later. if you want to upgrade to fuel injection then install a good running LS engine and get the computer remapped for your design, gear ratio, exhaust etc. the LS, in my opinion, is the new small block chevy. sorta like the old days when everybody was swapping in the small block where the old inline 6 used to live.
thats just me though. if you love the small block then do what you want, it's your hotrod. electronic engines will also need some sort of speedo revamp because there is no speedo cable adapter in the trans. more money to account for
in the end do a check of what you really have and what needs you have, then do a study to back up your plan. then look at it like someone from the outside would and decide, logically and budget wise, what your plan will be.
most importantly---take pics and post them as you go.

Solid advice, thanks. Most of which I had done before ever buying the truck. I would hope most ppl would have a good grasp on the financials before stepping into a project like this. Sure there are always hidden costs. Fortunately for me I am in no hurry. So if it takes 5 yrs then it takes 5 yrs. My wife is onboard with everything as long as I don’t hock her jewelry to do it 😳. I know I want to keep it as close to stock as possible. Im looking for that simplicity. I know I won’t be taking long road trips. I have new vehicles that would be more comfortable for that. I’m not interested in ifs or LS engines. So this post was just looking for advice on what would be the simplest and practical drivetrain swap for a mostly stock truck of this age. Less wiring issues. Less compatibility issues. And how to go about getting it.
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[Phungki]

Originally Posted by washington blue

A carburetor engine needs vacuum and mechanical advance to run it's best. Full Mechanical is at about 23-2600 rpm and full vacuum is at about 2000 rpm. Running the engine down the road slower than say 2300 rpm is not good for gas mileage and not good for the engine either. The reason to put an overdrive transmission in something is to get better mileage and less engine wear. Very hard to do with an overdrive trans hooked to a carburetor engine. The OP said he likes carburetors and he wants to keep the original suspension and he plans to drive around town and occasionally a few miles out of town. With this info a 700r4 would not be the best trans for him. Buy something like a 1975 Nova 4 door in nice shape and take the 350 engine and Quadrajet carb, th350transmission, driveshaft, and rear-end out of it and put them in the 56. Very straight forward simple swap. This way you have exhaust you might use and E brake cables and
lots of other little stuff too.

Thank you. I’ll keep an eye on cl for this.
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[washington blue]

If your wife is on board with this project then you have 90% of your problems solved already,lol.

[dsraven]

if it is just a power plant and trans you're looking to swap in, make sure to do a complete check of the engine and trans before shelling out the cash for it. oil pressure cold and hot. compression dry and wet. spark plug condition (sooty, oily etc). pull a valve cover and look for sludge etc. a complete running vehicle can also be pressure tested for cooling system leaks (like head gaskets etc). if you plan to "reseal" the engine then you might as well do a timing chain and gear set, valve seals, rear main etc. you can see how the prices can build on you quickly and come closer to being equal to a rebuilt. pull the trans pan and check for excessive black (usually clutch pack material indicating the clutch pack wear) or brass and/or aluminum pieces indicating bigger problems.try to pick up a complete running vehicle, possibly an insurance write off from body damage. a sport model with a stock 4 bbl carb may indicate a 4 bolt main block and big valve heads. most of the stuff you need will be in the donor vehicle you're scrapping. brackets etc. with that said, however, you are still gonna find that those parts may not fit. the accel pedal from a car,for instance, may have the totally wrong angle for a truck but is still not a deal killer. it makes some sense to make a list of all the parts you will need and price them individually from a "new parts" source and go from there. things like engine mounts may not be worth installing from the used engine due to age cracking or oil contamination. price out a rebuilt or crate engine compared to the used. same for the trans. if using a turbo 350 you may be able to source a rebuilt for not much more than the used.
just some ideas. if just cruising town with the old fashioned suspension then the engine/trans combo can be pretty basic as well. you could even use the stock trans cross member if you went with a std trans. there are bellhousings out there from the stock v8 that will wok and then you could use stock v8 engine mounts that attach to the front of the block. these trucks did come with the v8 option but would have had the old granny 4 spd tranny or 3 spd versions or, if you could still find one, a cast iron automatic trans that weighs as much as the truck.

[Chico 56]

Just about everyone on this board has more experience than me but I think my approach to the old truck was/is similar to yours. We have a 56 GMC in our family that sat for decades and I simply wanted a running, driving project. Maybe I could drive it to work once in a while on a Friday, to the dump or Home Depot if needed and always have something to tinker with when I had the time and inclination. It has a 283 and a four speed manual with a granny gear. I spent a bunch of time cleaning it up, trying to stabilize the deterioration of sheet metal where needed and getting the motor to run and the brakes to work. That was a big accomplishment. It needs a million things but I can drive it around now, it isn't rotting under a tree anymore and I can choose projects to take on as I feel like instead of getting bogged down in a major rebuild that might take years.

In your case, I might look for any old running GM motor that's available at a reasonable price that you can conveniently pick up. Looking through Craigslist near me, there are quite a few options--especially small and big block GM motors. From free to a few grand. Next, find a trans that will work. Again, quite a few near me that would work at a reasonable price. Then you can work on how to mount them and if major/minor work is needed, you'll know what questions to ask. You'll need some books and if you have any friends or family that know their way around old cars, enlist them occasionally, and then the endless knowledge, experience and expertise of the people here.
The great thing about these projects, especially the drive trains, is that they are so common and simple, lots of people have experience that you can learn from (parents, uncles, neighbors, forum contributors) and you can figure a lot out on your own.

Anyway, just thought I'd chime in since it seems like I was in a similar place a year ago. Once I decided that the priority was to have a drive-able truck and that lots of things could wait (paint, weather stripping, the perfect seat cover, windshield wipers, new shocks and springs), it got a lot simpler and I was able to make good progress knowing I'd have to retrace some of my steps when it was time to make improvements.

[Phungki]

Originally Posted by Chico 56

Just about everyone on this board has more experience than me but I think my approach to the old truck was/is similar to yours. We have a 56 GMC in our family that sat for decades and I simply wanted a running, driving project. Maybe I could drive it to work once in a while on a Friday, to the dump or Home Depot if needed and always have something to tinker with when I had the time and inclination. It has a 283 and a four speed manual with a granny gear. I spent a bunch of time cleaning it up, trying to stabilize the deterioration of sheet metal where needed and getting the motor to run and the brakes to work. That was a big accomplishment. It needs a million things but I can drive it around now, it isn't rotting under a tree anymore and I can choose projects to take on as I feel like instead of getting bogged down in a major rebuild that might take years.

In your case, I might look for any old running GM motor that's available at a reasonable price that you can conveniently pick up. Looking through Craigslist near me, there are quite a few options--especially small and big block GM motors. From free to a few grand. Next, find a trans that will work. Again, quite a few near me that would work at a reasonable price. Then you can work on how to mount them and if major/minor work is needed, you'll know what questions to ask. You'll need some books and if you have any friends or family that know their way around old cars, enlist them occasionally, and then the endless knowledge, experience and expertise of the people here.
The great thing about these projects, especially the drive trains, is that they are so common and simple, lots of people have experience that you can learn from (parents, uncles, neighbors, forum contributors) and you can figure a lot out on your own.

Anyway, just thought I'd chime in since it seems like I was in a similar place a year ago. Once I decided that the priority was to have a drive-able truck and that lots of things could wait (paint, weather stripping, the perfect seat cover, windshield wipers, new shocks and springs), it got a lot simpler and I was able to make good progress knowing I'd have to retrace some of my steps when it was time to make improvements.

Thx for the response. I’ve decided to do a frame off restoration. Since the fuel system is so old and needs replaced and the electrical and brake system is equally as bad it just makes sense to me to go that route. This truck sat for over 20 yrs and I feel if I just don’t go thru the whole thing I will be constantly chasing gremlins. I have picked up a couple books, one of which is a factory assembly manual. My stepdad is quite knowledgeable in regards to car restoration having done a few over the years and along with his vast array of tools I think we will tackle it. I’m sure it will take a couple years, maybe more but that’s ok with me. It’s just a hobby I’m looking to enjoy.
From what I have read, mostly on this awesome site, it seems that an 80s Camaro or Trans am might be the sweet spot if I can find the right one. Net me the 350, auto transmission and a posi rearend. I recently found out my brother in law has a good friend who owns a local salvage yard so might get lucky there.
I’ve lined up a local media blaster to do the frame and cab for me in The spring. In the mean time I will hunt down the patch panels I know I need now(likely to need more after it’s blasted). Find a few missing parts and cram as much information into my brain until spring gets here when I can start disassembly. Unfortunately my garage is small and I can barely get my TJ in it during the winter so I can’t do much until better weather arrives. Oh well, gives me plenty of time to formulate a plan and get everything found and/or lined up.
Thanks a bunch

[Chico 56]

Sounds like a good plan-- Keep us posted!