Here is some good info for the 2.4 swap into your neon. I'll use some info from neonsdotorg and from my swap. Need more help ask.
2.4 swap FAQ
How hard is a 2.4 swap into a Neon?
Okay let's get serious here. If you are not prepared to possibly be out of a car for a couple days, weeks, months then this is not for you. A 2.4 swap isn't incredibly hard. If you do not have the tools to accomplish this do not even attempt to try it. Some people have done it in 6 hours. They had all their cards straight and ready to go. It took me a couple of months because of work and parts. The 2.4 swap is not for the faint of hard and be prepared to spend money if necessary.
What 2.4 do I use? Where do I get it?
You can use a 2.4 motor from any of the following; 1995 to 2000 Stratus/Breeze/Cirrus, 1996-2000 Caravan/Voyager, 2001 up PT Cruiser/Stratus/Sebring. Realize that all the common install kits available utilize the right side engine motor bracket from a 95 to 2000 Stratus/Breeze/Cirrus. All 2001 up 2.4 motors have a lightly different head port and manifold mounting configuration so you have to modify your intake and exhaust manifolds to use that motor. That does include the PT Cruiser. 2001 up also have a different oiling system and different oil filter locations. In Late 1996 the timing belt tensioner was changed so the later tensioner is preferred. Get your motor from a local wrecking yard.
What tranny do I use? 3.94 manual or 3.55 manual? Can I use an automatic? What about the 4 speed auto from a stratus?
You can use either manual tranny you want. Just realize the 2.4 puts out a lot more torque especially on the low end so be prepared to spin the tires. A 3.55 tranny will gain you better gas mileage most likely along with easier launches. There is no definitive as to which is better so I say use what you got available to you and you will be pleased either way. As for the automatics, you can use the 3 speed automatic that came standard in lots of Neons. It is a tight fit but works fine. The tranny loves the torque. You must use a Neon DOHC automatic computer when using the automatic transmission. The 4 speed auto from a Stratus/Breeze/Caravan will not work in the Neon. Number one there is not enough room and number two it is computer controlled and there isn't a computer that can control it and work well with the Neon.
What ECU do I use? Would a MPP ECU for the DOHC be beneficial or is it better to use a stock DOHC ECU?
Use a computer for a Neon! You can use any DOHC computer you want as long has it is for the same year as your car. You can use a Mopar Performance, Howell AF/X street or strip, or you can use a stock DOHC computer. You won't need the higher rev limiters of the aftermarket computers because the 2.4 doesn't generally make much power part 6500 anyway without serious mods. If you are using the automatic transmission then get a DOHC Neon computer from an automatic car. Easy as pie.
Will the 2.0 and 2.4 heads interchange?
Yes the 2.0 and 2.4 heads are the exact same head. They are the same casting number. The difference is the cam gears and the cams. You can use a 2.0 exhaust cam on your 2.4 motor and gain some HP. You must use 2.4 cam gears.
What's the deal with the PT Cruiser 2.4L head?
The PT Cruiser head has a slightly different (and better) port design, and the manifold patterns are different. The head will bolt right onto any 2.0L or 2.4L engine. PT head with a dohc intake manifold will require drilling new mounting holes. Easiest solution is to buy a 2002 Caravan intake manifold gasket and use that as a template.
What will I pay to purchase a 2.4 motor?
For a running motor expect to pay anywhere from $500 to $1500 dollars depending on mileage, age, and/or condition of the engine you are purchasing. I got my complete PT engine for free because the guy blew the head gasket. The price (or lack of) was the only reason I did the swap. Depends on where you are in the country also.
Why are you using 24lb injectors? Do I have to change the fuel system?
You can use the stock injectors anytime as long as you use an adjustable fuel pressure regulator with them. If you use 24lb injectors you don't need the regulator but it is suggested for tunablity of the engine to your mods. Yes you can use some kind of piggy back fuel controller like the Apexi SAFC or a Split Second ARC1. You still must use 24lb injectors to be on the safe side. The 2.4 motor is bigger, makes more power and needs more fuel to satisfy it thirst. Feed it well and it will be good to you. Feed it to little and it will lean and blow up. You can also swap a 2g fuel pump and use stock injectors. Neon runs 49 psi, 2g runs 58.
Where do I get 24lb injectors?
You can use Accell or Ford Motorsport injectors. Actually some Dakotas came with 24lb injectors. Search around. Just be sure to get the Bosch style connector from the 1995 to 1996 Neon. You will have to change your engine harness a little. Get the right connectors from the auto parts store and splice them in.
The two types of injectors on Neons are EV1 (which most people know as the Bosch style on 95) and the EV6 (on most 95.5-up). EV6's are actually a Bosch design too. EV1's are also known as "Bosch Rectangle" and EV6's are also known as "Bosch Oval". This refers to the shape of the connectors. Neons require a "High Impedance" injector (11-16 ohms). Most domestic cars do.
Since most Neon owners had EV6's, and most available/popular injectors for upgrade were EV1's, a connector swap was usually required. Not difficult, just a minor PITA. EV6 injectors have been available for a while, but were usually more rare, and expensive in the larger sizes.
Here's a link with pics of both connector types. This site is also a good cross reference for any size injector you want. I'm trying to find a more complete cross reference, because some newer injectors aren't there.
The GOOD news is that (05-up) stock Mustang GT's use 24lb injectors, and are EV6 type. This means they're a direct fit for most 95.5-up Neons. The Ford part # is 4L8E-A4A. or Motorcraft CM5088
The GREAT news is that right now, they're CHEAP! on ebay, or the Mustang Forums, due to the number of GT owners swapping them out for supercharger upgrades.
Check out these cool sites. Learn more about injectors, and how to properly feed your BEAST!
Will a 2.4 crank work in a 2.0? Will 2.4 rods work in a 2.0?
No and No. 2.4 has a longer crank and block casting. The 2.4 uses longer rods and they won't work in a 2.0. And that goes the other way too. Use 2.4 crank in a 2.4 and use 2.4 rods and pistons in a 2.4.
How much does the 2.4 weigh in relation to the 2.0 I'm replacing?
There is a 50 pound difference between the blocks. 2.4 block is taller and longer thus weighs more.
Will my '95 non-modular flywheel and clutch bolt up to the 2.4 motor?
Yes it will. The 2.4 and the 2.0 use the same style flexplates. Not a problem. You can use a modular or non-modular clutch and flywheel on your 2.4 swap.
Is there a performance advantage to removing the balance shafts?
Yes there is, parasitic loss HP can be found this way along with dropping about 15-20 pounds from the car. You must use more oil in the car without the shafts and you must plug the oil passage. You will feel an increase in vibration upon removal of shafts.
What exhaust do I use?
You can use the completely stock exhaust system from the manifold on back. The motor responds wonderfully to exhaust mods so they are recommended.
Why the DOHC IAC and TPS?
The sensors are different for a DOHC from a SOHC because of clearance issues with the different intake manifold so you must change them. I'm sure you can make the SOHC sensors work but I don't recommend it because they aren't designed to work with that intake manifold.
What TB can I use?
You can use any TB you want from a stock 49mm all the way up to a 60mm from Modern Performance.
What engine harness do I use?
You should use a DOHC Neon Harness for ease of installation. You can use a SOHC harness but it will require more cutting and splicing. If purchasing a harness purchase one from a similar year model to your vehicle. Get a DOHC just because of the ease of installation.
What hood do I use? Can my flat SOHC hood fit?
The SOHC hood will not fit a 2.4 motor swap into a neon using a common kit. You must use a stock DOHC hood. You can use a fiberglass/carbon fiber DOHC hood. You can use a CNNP Racing Cowl Hood. A Howell AF/X AAR style hood will not clear a 2.4 swap using a common kit.
Will a Hahn Racecraft Turbo kit for a 2.0 DOHC Neon fit on my 2.4 swap?
Yes it will. Modifications may or may not include running lines differently and such. Use you best judgment. The main part, turbo and manifold, bolt right on no problem when not using a 2001 and up engine.
I have a 2nd Generation Neon (2000-up) I want to put a 2.4 in it. How can I do it?
First off no one to my knowledge has swapped a 2.4 in to a 2nd generation Neon. You must use the right side engine mounting system from a PT cruiser if attempting the swap. You can use an older 2.4 block but it may require slight mods to get the mounting system to work. As for the computer use a PT Cruiser computer. If you have Sentry Key, then I wish you luck because the computer uses a code from the key to start the vehicle so changing computers would be a problem
Parts list, Tools
Stratus mounting plate 2.4 adapter (passenger side)
MPx udp pulley EGR block off kit
DOHC wiring harness
DOHC intake manifold
DOHC fuel rail
DOHC TPS and Idle air control
DOHC knock sensor
DOHC upper rad hose
DOHC lower rad hose
DOHC thermostat housing
DOHC header DOHC plug wires
Thermostat At least a pt clutch is needed. Get a new t/o bearing. Intake (iceman, 3.0)
DOHC "Power Bulge" Hood
assorted fluids and such
Bosch style injector plugs can be purchased from Autozone if necessary
Complete set of hand tools, and I mean complete. 3/8, 1/2, and 1/4 drives with all metric sockets, swivels, good torque wrench, and extensions. air compressor with impact, ratchet, and cut off wheel are needed. Good set of different size and length screw drivers. Assorted flat and rat tail files. Tierod and balljoint separator forks are also recommended. Big huge pry bar,engine hoist and chains, jacks, jack stands, bench grinder, hacksaws, and a vice are extremely helpful!
Okay now lets put it in step by step the best I can.
Remove battery and battery box.
Get car up in the air on jack stands and take wheels off.
Unbolt tierod end from steering knuckle.
Unbolt lower ball joint. Use big pry bar push lower control arm down popping ball joint out of the steering knuckle. Take axles out off completely or support them so they do not hang and damage the CV assembly.
Disconnect upper and lower radiator hoses.
Disconnect heater hoses.
Remove the radiator over flow bottle.
Disconnect hard vacuum line from evap purge solenoid that is attached to right side motor mount. the hard line Runs through the intake manifold, slide it out once motor is out of car.
Disconnect P/S reservoir from back of head.
Disconnect fuel line from fuel rail.
Remove throttle cable(s) and auto trans kick down if applicable.
Disconnect wires going to the starter.
Remove tranny cables.
Disconnect exhaust manifold from exhaust at the donut/collector, if you have a header remove header. Bolt chains to back of block.
Take off front motor mount and front motor mount bracket for clearance.
If you have manual trans unbolt bobble strut.
Remove two fluid lines going to the tranny from the radiator if you have an auto.
Unbolt A/C strap it to lower radiator support. Unbolt P/S pump and move it to right side inner fender between cowl and strut perch.
Remove the hood.
Chain motor to hoist and unbolt side mounts, carefully remove motor by twisting it out, watch those heater lines!!! For ease of removal and installation both radiator and fans should be removed.
Okay motor is out.
Cut center support out of intake manifold to clear knock sensor and dipstick.
Install injectors to fuel rail; be sure to use petroleum jelly on the o-rings so you don't damage them.
Install intake manifold.
Take upstream o2 sensor off old motor's exhaust manifold/header and install on new header.Leave header off to the side, we will get to it after the motor is in.
Install EGR block off plates. If you bought your kit from Vitor you won’t have to worry about EGR CEL with stock computer because of the resistor that comes in the kit. If you so desire, you can make the 2.0 DOHC EGR systems work with minimal modification.
Install throttle body from 2.0 motor on to the 2.4. I used the same 60mm Modern Performance throttle body I had on the old 2.0 DOHC. Take that hard vacuum line from throttle body to evap solenoid and run it through the intake manifold to the throttle body.
Pull off the stock 2.4 pulley from motor and toss to scrap pile
Since you have the old pulley off, if you so desired now is the best time install a set of cam gears and along with a new timing belt.
Might as well replace the water pump and oil pump now.
Remove starter and tranny from old motor and put on new motor BE SURE TO USE LOCTITE ON THE FOUR BOLTS THAT HOLD THE FLYWHEEL TO THE FLEXPLATE/BOLTS THAT HOLD THE TORQUE CONVERTER TO THE FLEX PLATE TIGHTEN THE HECK OUT OF THEM. THE FACTRY SERVICE MANUAL SAYS TO REPLACE THE BOLTS, IF YOU CHOOSE TO DO SO THEY HAVE LOCKTITE ON THEM IF YOU ORDER THEM FROM THE PARTS COUNTER AT YOUR LOCAL DEALERSHIP. TORQUE TO FACTORY SERVICE MANUAL SPECS.
None of the old support brackets from the tranny to the block of the 2.0 will fit. Just put them in the recycled metals pile. Remove alternator from old motor and install with pt bracket.
I used 2.4 cams in my car to start with. If you are using 2.0 cams all you need to do is cut the nipple of the cam magnet and rotate it 90 degrees. Best way is to mark it, turn it 90 and mark it again. It’s not rocket science.
The pickup on the crank trigger for the 2.4 are different from the 2.0 as you all know so some wiring must be changed for the 2.4. It is as follows:
Take the injector harness and move the plugs to the right. Label everything so you don't accidentally mix them up. You may have to change the plug itself to work with the Accel injectors. Basically it's like this.
Injector plug 1 must be plugged into injector 2.
Injector plug 2 must be plugged into injector 3.
Injector plug 3 must be plugged into injector 4.
Injector plug 4 wires must be extended so it can be plugged into injector 1.
Now there are three wires on the coil pack plug. Take the 2 outside wires and switch them. Leave the center wire alone.
Extend the wire for the knock sensor.
Finish setting up your harness by putting it all in place change connections as necessary to work with the sensors that you are not changing from the motor.
Remember to check the speedometer sensor connector especially if you are using an auto trans. Double check all the sensors and connectors again to be sure they are plugged in and tight.
Remove A/C bracket from 2.0 and install on 2.4 can only use 3 of the five bolts. Take 2.0 P/S bracket and give it to a friend. Use a PT P/S bracket, slot the holes for adjustability. This option is probably the best rather than cutting the fragile cast aluminum 2.0 bracket.
Cut front motor mount to clear the oil pan. It doesn’t take much.
Okay if you haven't already taken off that right side fan, trust me it's worth it take it off now. If the motor is all wired and the tranny is bolted on tight to the motor hoist it up and lets squeeze it in literally!
Okay tranny side first, if you have an auto good luck man because you won't think it will fit from the top at all, but it will! Literally wiggle is slowly into the bay. You will have to twist the motor to clear the tranny. Motor and tranny will be an extreme downward angle. Watch the heater lines so they don't hit the cowl!!! Get motor in the bay really low, install tranny mount to tranny. Now lift tranny with spare jack into place. Put bolt through mount tighten it down.
Install pass mount to inner fender/frame rail then using the hoist lift the motor up to put the bolt through put nut on it and tighten it down.
Yes it’s in! Remove the hoist. Now for the real fun.
Bolt the a/c compressor to the 2.0 bracket you installed earlier.
Bolt the p/s to the PT bracket.If you had a SOHC the p/s reservoir will not fit right but that can be creatively held in place. You may need to reroute the hardlines a little bit, use your best judgment but do not crimp them in any way.
Install the FMM.
DON'T FORGET THE GROUND FROM THE WIRING HARNESS RIGHT BELOW THE STARTER!!!
Reinstall a/c compressor. Remove the factory 2.4 exhaust manifold...put on 2.0 DOHC header or 2.0 DOHC exhaust manifold. Hook up exhaust.Now you can hook up the o2 sensors. Put the right side fan back in if you choose to. You must put the left hand side on back on, but the right one is optional unless you have the small radiator and didn’t have the right hand fan in the first place.Make sure you got the ground that goes from the fender to the back of the head bolted down.
Make sure that ground on the upper radiator support is good
Hook up engine harness to fuse box and computer check the o2 sensors so the wires aren't rubbing on anything hot.
Make sure you hooked up that speed sensor in the tranny if you didn't put it when you installed the tranny. if you have an auto trans hook up the two lines running from the radiatorInstall thermostat and thermostat housing to the intake manifold
Stock DOHC upper radiator hose works fine, install it
Cut inch of top and bottom of lower DOHC radiator hose to fit it in place. You may need a little more or a little less but it will fit fine once cut.
Okay check the wiring again the best you can.
Check timing one last time, then install udp and belts. YOU MUST USE AND UDP.
Shorten heater hoses coming from the firewall to hook up to the 2.4. I cut the bracket that holds the two hard heater lines together so I had more room to hook it up.
Remember the top hose from the firewall will hook to the hard-line that's on the passenger side. The lower heater hose coming out of the radiator goes to the driver’s side hard line.
Install overflow tank and hook up line to thermostat housing. Make sure that the hard vacuum line from the throttle body to the evap purge solenoid is hooked up. Evap purge solenoid is normally attached with a sheet metal screw to the right motor mount; I did not put it back, and moved it slightly and secured it creatively.
Check your fluids, I needed 4 quarts of tranny fluid in my mtx.
Fill it full of antifreeze.
Reinstall the axles.
Now put axles where they are supposed to be and start slowly putting strut back in place while installing the axle at the same time. Once the axle is seated get out the pry bar push that lower control arm down. Move ball joint stud into place and slowly let the control arm up putting the stud into its spot on the knuckle. FACTORY SERVICE MANUAL CALLS FOR REPLACEMENT OF THIS BOLT. WE CHOSE TO IMPACT THE BALLJOINT BOLT BACK INTO PLACE WITH OUT REPLACING IT OUT OF HABIT. MAKE YOUR BEST CHOICE BUT PLEASE TORQUE TO PROPER FACTORY SERVICE MANUAL TORQUE SPECS OR YOU WILL BE IN A HEAP OF TROUBLE LATER. IT MUST BE VERY TIGHT.
Check the upper three strut nuts to make sure they are tight. Reinstall the tierod to the knuckle and tighten it down.
Check the three grounds one last time for safety, one bolts to the back of the head. Another bolts to the bellhousing of the trans below the starter, and the third is the little one that goes to the upper radiator support using an 8 mm sheet metal screw.
Install battery box and battery
If everything is installed and tight, turn the key to on and prime the fuel rail. Listen for the fuel pump. Try and start the car. If it runs, good for you.
If it doesn’t…
Does it have fuel and spark?
Did you switch the outer coil pack wires?
Did you move the injectors down 1?
Did you remember all the grounds?
Is the crank sensor good?
Is the timing good?
If you’re using 2.0 cams, did you rotate the cam magnet?
If the car won’t start, try unplugging the cam sensor and turning it over.
This swap is pretty easy if you have a garage to do it in, an engine hoist and stand, and an air compressor. My swap took a while because I had to wait on injectors. I also switched the cam and coil sensors for the pt ones not knowing those wouldn’t fit. Putting the neon ones back on I switched the 2 and fried my MP Ecu. I didn’t catch this for a long time as the sensors are the same. I tried everything to get the car to start, but it wouldn’t with a bad ecu. I’d also recommend not installing the udp until the last minute.