4.3L swap?

[tkgibbs27]

i have an old GMC van that has been sitting around for the past, i would say six years, it has a 4.3L engine in it. would it be possible to drop this engine into my manche? would it even be worth while? figured since i still have that junker sitting around, rather than spend any more money than i have to, that i might give it a go, that is if it would even be worth it.

[Eagle]

Is it possible to install a 4.3L into an MJ? Yes -- a guy I used to know did it in an '86 XJ some years ago. "Drop in"? Not a chance. Remember, the 4.3L is a shortened small block V8 -- it's very wide compared to the 60-degree 2.8L and 3.4L engines. It also doesn't use the same bell housing pattern as the 2.8L and 3.4L, nor the same as a Jeep 4.0L, so you either have to use a Chevy tranny and transfer case or buy adapters, which are the same as you'd need to use a small block V8.

 

I asked the guy near me if he would do it again and he said "Hell no!" Basically, it's all the work of putting in a small block V8, with a less satisfactory result. If you already have the engine and feel it's worth the effort you can make it work, but IMHO there are better solutions to repowering an MJ.

[tkgibbs27]

i don't have the V8. it's a 6 cylinder. is there any difference between the two?

right now it sounds like there's quite a lot more work that i had thought. guess i'll sell the junker to afford a new engine then.

 

what might you suggest, engine wise? some have suggested the 3.4L.

[DirtyComanche]

Pingpong has an XJ with a 4.3 in it.

 

Hard swap? Wouldn't say so, just a lot of stuff that has to be done. Is it a TBI engine, or vortec, or carbed? I'd not bother with a carbed setup, unless you ran propane, but that's a hole 'nother bridge.

 

You'll need some funky headers, or the stock cast exhaust manifolds. You'll need to adress the fuel system (depending on type). You'll need another tranny - whatever you have now will probably not be up to a 4.3 on way or another. The one in the van may or may not be useable.

 

Then there's cooling. A 4.0 rad would get the job done. And you'll need to change your fan setup - I'd suggest electric.

 

You can buy motor mounts from AA. I'd probably not.

[Eagle]

i don't have the V8. it's a 6 cylinder. is there any difference between the two?

right now it sounds like there's quite a lot more work that i had thought. guess i'll sell the junker to afford a new engine then.

 

what might you suggest, engine wise? some have suggested the 3.4L.

I understand that you have the V6. My point is that the 4.3L GM V6 is a wide, 90-degree engine that is basically a Chevy small block V8 with two cylinders chopped off. There is nothing about it that's compatible with an XJ or MJ.

 

By contrast, the GM 2.8L/3.1L/3.4L V6 is a smaller, narrower 60-degree engine. The 2.8L version was used in the 84 thru 86 XJ and the 86 MJ, and it's the same block as the later 3.1L and 3.4L. Being smaller, lighter, and narrower than a 4.3L, all things being equal the 3.4L is a much better choice for an MJ because you can use MJ motor mounts, transmission, transfer case, exhaust system, etc.

 

Your original question used the expression "drop in." That suggested to me that you're looking for an easy swap. The 4.3L can be done and has been done, but it's far from being a "drop in" swap.

[tkgibbs27]

Pingpong has an XJ with a 4.3 in it.

 

Hard swap? Wouldn't say so, just a lot of stuff that has to be done. Is it a TBI engine, or vortec, or carbed? I'd not bother with a carbed setup, unless you ran propane, but that's a hole 'nother bridge.

 

You'll need some funky headers, or the stock cast exhaust manifolds. You'll need to adress the fuel system (depending on type). You'll need another tranny - whatever you have now will probably not be up to a 4.3 on way or another. The one in the van may or may not be useable.

 

Then there's cooling. A 4.0 rad would get the job done. And you'll need to change your fan setup - I'd suggest electric.

 

You can buy motor mounts from AA. I'd probably not.

 

i know it's not carbed. it's in a 95' gmc safari. i don't know if it's tbi or vortec, i haven't check, i just know it's a 4.3L and that's really about it and it's fuel injected.

[tkgibbs27]

i don't have the V8. it's a 6 cylinder. is there any difference between the two?

right now it sounds like there's quite a lot more work that i had thought. guess i'll sell the junker to afford a new engine then.

 

what might you suggest, engine wise? some have suggested the 3.4L.

I understand that you have the V6. My point is that the 4.3L GM V6 is a wide, 90-degree engine that is basically a Chevy small block V8 with two cylinders chopped off. There is nothing about it that's compatible with an XJ or MJ.

 

By contrast, the GM 2.8L/3.1L/3.4L V6 is a smaller, narrower 60-degree engine. The 2.8L version was used in the 84 thru 86 XJ and the 86 MJ, and it's the same block as the later 3.1L and 3.4L. Being smaller, lighter, and narrower than a 4.3L, all things being equal the 3.4L is a much better choice for an MJ because you can use MJ motor mounts, transmission, transfer case, exhaust system, etc.

 

Your original question used the expression "drop in." That suggested to me that you're looking for an easy swap. The 4.3L can be done and has been done, but it's far from being a "drop in" swap.

 

my bad, i thought you were referring to a v8. i know that i would have to replace quite a bit of parts if i did the 4.3L swap. i should have worded my original question better then. no i am just looking for a much better engine all around, rather than having that gutless piece of $#!& 2.8L. about the only good use for that would be an anchor.

[Eagle]

... i am just looking for a much better engine all around, rather than having that gutless piece of $#!& 2.8L. about the only good use for that would be an anchor.

Ah. Now we're getting somewhere. You hadn't previously said what engine is in your MJ. Since you have a 2.8L, the logical swap for you is a GM 3.4L (must come from a rear-wheel drive vehicle such as a Camaro). The block is the same as the 2.8L, so you don't need motor mount adapters, you can use your existing bell housing and transmissions, etc. YMMV but if I were in your situation I would sell the 4.3L and buy a 3.4L.

[tkgibbs27]

... i am just looking for a much better engine all around, rather than having that gutless piece of $#!& 2.8L. about the only good use for that would be an anchor.

Ah. Now we're getting somewhere. You hadn't previously said what engine is in your MJ. Since you have a 2.8L, the logical swap for you is a GM 3.4L (must come from a rear-wheel drive vehicle such as a Camaro). The block is the same as the 2.8L, so you don't need motor mount adapters, you can use your existing bell housing and transmissions, etc. YMMV but if I were in your situation I would sell the 4.3L and buy a 3.4L.

 

i assumed you already knew, suppose i shouldn't assume. you had given me a bit of information in another topic that was about swapping the 2.8L with the 258 I6, i don't know if you remember that topic.

 

so the 3.4L fit right in? i won't have to worry about what's already equipped on the truck not being powerful enough for the 3.4 then?

[JeepcoMJ]

so the 3.4L fit right in? i won't have to worry about what's already equipped on the truck not being powerful enough for the 3.4 then?

 

the 3.4 will be as direct of a bolt-in as you can get. bolt the 2.8 motor mounts, oil pan, and exhaust manifolds onto it, and it will bolt in.

 

try and find a 3.4 that matches your trans (i.e. auto if you've got an auto trans, or manual if you have manual), otherwise you CAN put your 2.8 flexplate/flywheel on the 3.4 but it will need to be neutrally balanced by a professional shop (not too much $$$...like $60)

 

you will want the entire engine wiring harness and computer from the camaro (computer is under the hood), must be a 90-93/94 camaro or firebird with a 3.4. I'll give you all the diagrams to alter the harness as needed (zero soldering will be needed).

 

you will also need to get a VATS antitheft bypass...it's a little computer box that puts out the ignition signal to the computer (pin 55 in the computer), which grounds the injectors. $30 or so shipped from http://mysite.verizon.net/vze7erz1/id1.html

 

the only other thing you will need is an inline fuel pump (or a 4.0 in-tank fuel pump with pressure regulator) that puts out the proper psi for the 3.4.

 

that's a full list of the mods, and while it may seem like alot...it really isn't. the mechanical bolt-in part makes it real easy. you could do it in 2 or 3 weekends by yourself, 1 or 2 if you have the motor ready to go beforehand, or 1 or 2 with 2 guys.

[pingpong]

Sorry I haven't been on in a while, but work does that.

 

To do the 4.3 swap is pretty basic if you are going to run drivers drop axle.

Advance adapters sells the mount kit for under 200 (really a good deal if you ask me.. saves a lot of frustration) but it moves the ngine over to the passenger side... bad if you plan on running a dual case passenger drop setup (pong)

 

Painless wiring makes a nice wiring kit for it, kinda pricey but if you can pull the whole wiring setup from the donor.. no need

 

If you run a 700r4 there are a few companies that make adpaters (clocking rings) for them.. or you can run a np207 or np208

 

The isue with the t-case is you need a t-case shifter setup.

 

I am still working on finishing this swap.. I have to finsh hooking up the trans, and install driveshafts... maybe I will get to that here soon

[tkgibbs27]

so the 3.4L fit right in? i won't have to worry about what's already equipped on the truck not being powerful enough for the 3.4 then?

 

the 3.4 will be as direct of a bolt-in as you can get. bolt the 2.8 motor mounts, oil pan, and exhaust manifolds onto it, and it will bolt in.

 

try and find a 3.4 that matches your trans (i.e. auto if you've got an auto trans, or manual if you have manual), otherwise you CAN put your 2.8 flexplate/flywheel on the 3.4 but it will need to be neutrally balanced by a professional shop (not too much $$$...like $60)

 

you will want the entire engine wiring harness and computer from the camaro (computer is under the hood), must be a 90-93/94 camaro or firebird with a 3.4. I'll give you all the diagrams to alter the harness as needed (zero soldering will be needed).

 

you will also need to get a VATS antitheft bypass...it's a little computer box that puts out the ignition signal to the computer (pin 55 in the computer), which grounds the injectors. $30 or so shipped from http://mysite.verizon.net/vze7erz1/id1.html

 

the only other thing you will need is an inline fuel pump (or a 4.0 in-tank fuel pump with pressure regulator) that puts out the proper psi for the 3.4.

 

that's a full list of the mods, and while it may seem like alot...it really isn't. the mechanical bolt-in part makes it real easy. you could do it in 2 or 3 weekends by yourself, 1 or 2 if you have the motor ready to go beforehand, or 1 or 2 with 2 guys.

 

http://www.autopartswarehouse.com/detai ... TC453.html

 

would this be considered the engine wiring harness? it says body, but i am not sure.

[JeepcoMJ]

nope.

 

you have 2 options here.

 

1. get a painless wiring harness, and go with an edelbrock 4bbl intake and a holley 390cfm carb, or even make the camaro/firebird computer work with the painless kit (almost impossible).

 

2. get a motor from a donor car. best to get the whole car (rear end accident, w/e), and gut it. you particularly want the engine bay harness and computer, and all related sensors to the engine. by doing it like so, you can simply cut out the things you don't need and use only the essentials for running the motor. this way there is nothing that could go wrong except cutting the wrong wire. in which case, check, double check, and check again before you cut.

 

the second method includes every single part that you would need to make the truck run with the camaro motor in it, at a lesser cost. cost this way should be around $600 for the whole car, but if you get it for less than $1200 you're doing fine. buy a rebuild kit ($400) and go through the motor now, or simply put all new gaskets on it except head gaskets (this way you don't have to do a complete teardown), and you don't have to spend $400 on a wiring harness.

 

and...I can get you the necessary diagrams

[tkgibbs27]

nope.

 

you have 2 options here.

 

1. get a painless wiring harness, and go with an edelbrock 4bbl intake and a holley 390cfm carb, or even make the camaro/firebird computer work with the painless kit (almost impossible).

 

2. get a motor from a donor car. best to get the whole car (rear end accident, w/e), and gut it. you particularly want the engine bay harness and computer, and all related sensors to the engine. by doing it like so, you can simply cut out the things you don't need and use only the essentials for running the motor. this way there is nothing that could go wrong except cutting the wrong wire. in which case, check, double check, and check again before you cut.

 

the second method includes every single part that you would need to make the truck run with the camaro motor in it, at a lesser cost. cost this way should be around $600 for the whole car, but if you get it for less than $1200 you're doing fine. buy a rebuild kit ($400) and go through the motor now, or simply put all new gaskets on it except head gaskets (this way you don't have to do a complete teardown), and you don't have to spend $400 on a wiring harness.

 

and...I can get you the necessary diagrams

 

ahhh. well i basically had it set in mind that i wasn't going with a carb.

i don't have the room for another vehicle, there's already six, plus another and a body in the garage so i planned on just getting the engine out of a firebird, computer and wiring harness themselves. found these guys and they have the engine for sale on their website, would make things a bit easier, but haven't decided on whether i want to go this way or pick one up at the junk yard: http://www.rebuilt-chevy-engines.com/lo ... engine.cfm

 

what are the other related sensors for the engine?

alright, that would be nice. i guess you could get them to me whenever, now or later.

[JeepcoMJ]

I'm not sure what else is related to it sensor-wise. mostly what's on the engine. you neeed the same computer from the same engine...there is a chance that they'd give you the wrong year computer and then it wouldn't run well.

 

so, IMO you'll want a junkyard motor, and if you can con them into chopping the car in half or just yanking the motor nicely and letting you do the wiring harness, that is the way to go.

 

I wouldn't trust them yanking the harness (or the motor for that matter, wires will probably be cut in the process), but if you can't get the whole car to your place, then that's your option.

[feerocknok]

OT: What is it called when you buy just the front half of the car?

[jtdesigns]

OT: What is it called when you buy just the front half of the car?

 

You talking about a front clip?? When they cut the front off a uni-body and then weld it back on a smashed car?

[JeepcoMJ]

there's nothing to say but "front half" or "from dash forward"

 

front clip is the fenders, bumper, hood. not any support or any engine etc.

[feerocknok]

I was thinking there was a name for the front half deal where they saw the unibody off behind the dash. I'll see if my pops remembers.

[StevenH]

I just wanted to chime in and say I am doing a 4.3 swap in mine as soon as advance adapters gets my parts here. I am doing a 4.3/th400/d300, I have a 9" underneath it now and a passengers drop d44 will be here one day this week. Mine will be carb though, that's a big difference from your swap but I have messed with TBI a little bit and might can help some.

 

Browse around at www.v8s10.org

[tkgibbs27]

I'm not sure what else is related to it sensor-wise. mostly what's on the engine. you neeed the same computer from the same engine...there is a chance that they'd give you the wrong year computer and then it wouldn't run well.

 

so, IMO you'll want a junkyard motor, and if you can con them into chopping the car in half or just yanking the motor nicely and letting you do the wiring harness, that is the way to go.

 

I wouldn't trust them yanking the harness (or the motor for that matter, wires will probably be cut in the process), but if you can't get the whole car to your place, then that's your option.

 

well we don't have pull it yourself type of place here in the tri-cities, so they would pull the engine for me. i don't know about the wiring harness though, i know they will let you check out a specific vehicle if you ask, but they won't let you pull anything yourself. i will have to stop in there or call to see what can be done.

 

i think the closest pull it yourself type of place is in spokane, that's about a three hour drive i believe. not to bad.

 

i don't have a trailer to pull the front of the vehicle with if i can get the front half chopped off, can't think of any friends who have a trailer small enough for the manche to pull. do you think it would be fine to just have them put it in the back of the truck?

[JeepcoMJ]

nope, it'll collapse your bedrail.

 

best bet is to find one that's crunched, spend a day dropping the entire front subframe with engine/trans intact, gutting the harness, interior, and anything good off the car, then sawzall it up and haul the chunks to the scrapyard.

 

a given weekend will be enough time to accomplish that.

[tkgibbs27]

ahh i see. would i be able to just put the motor in the bed without problems arisen?

 

mostly likely it would be. well i'll see what comes up. i'll probably take a trip up to spokane to get all the stuff. i can't do that until mid-jan.

[feerocknok]

I think he meant that if you had to set part of it onto your bedrail (the top of the sides), it would collapse them.

I have no idea how much weight a Manche can hold in its bed, but the first problem that would arise from too much is failing brakes. The weight of half of a vehicle probably wouldn't go over the limit, but would come close.

[tkgibbs27]

i am sure it would collapse them, they aren't that thick. i don't have a clue either. that would make sense, well i will think of something