Hey, Im new to the forum and new to owning a Neon. I just purchased a 1995 SOHC Neon with 84,000 miles. I was wondering what would be involved in swapping over to the DOHC head, if the motor is infact the same as the Eclipse N/A, can a reman from a mitsubishi be used, or an Avenger? Is the labor involved worth the gain? I assume that i would have to obtain a new PCM, but are there a large amount of other parts that are needed? I have pretty extensive expierience in diy/mechanics with four cylinders and have rebuilt the top-end on a 95 Eclipse before, just trying to find out what I'd be getting myself into. I figure thats enough questions for my first post, any input would be appreciated, Thanks.

 

i would stick with the sohc head. It is suprisingly a very good little engine. when i had my car i beat si's and a couple of other cars that had the same thing as me. All you have to do is add things. If you want a new head just get yours port and polished. but other than that stick with the engine you have. Its a very reliable engine

 

In my opinion, the SOHC is a better and more modable than the DOHC. But if you wanna swap you will need a PCM. The motors are the same, but they are mounted reverse in the eclipse.

 

I am in the process of doing a SOHC to DOHC right now - I blew my engine racing last year - I picked up a 97 and a 98 SOHC engine last month - going to take my DOCH from my 96 Neon and put it on one of the SOHC engines. I was hoping to have most of it completed this past weekend - but I ended up working at my Job instead of my my car - which now I am not sure if I will have the car ready for the race this weekend!

I was planning on posting progress as I do the engine swap - I have my old engine ready to be pull from the car - and I already pulled the SOHC engine and put it on a Engine stand.

Let me know if you do it!

Greg


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I would stay with the SOHC, i have a 95 SOHC and its a strong engine, especially with what i have on it.

 

The Mitsubishi version is reverse flow. Won't work without lots of work and fabrication on your part.

The DOHC head on the SOHC block will lower compression by about 0.5, so you're looking at 9.3:1 or so. There are some slight modifications needed to the wiring harness (unless you get a DOHC harness) since a couple of sensors move around (coolant temp being the obvious one). You'll want the DOHC computer to run it - significantly different timing and fuel curves.

The DOHC has much more potential than the SOHC. If that isn't obvious...

A complete engine swap would actually take less time and effort. Going the 2.4L is another option.

Best of luck!

 

i actually just did this. My DOHC blew a rod and i could only find a SOHC motor around here. You will need the ECU or it run lean and you will need the pistons (i would try for ones already on the rod) if you want the compression of a DOHC and the whole top end,including intake and exhaust manifolds. Its actuall rather simple just kind of exspensive and time consuming. The timing belt from mopar is the best that i have found ($100). You will also need rod bearings. Piston rings, and upper gasket kit which i recomend Mopar for that also.

 

I was under the impression that the block was the same for both models, if this is the case swithching out the heads would be much easier than pulling the motor. Can anyone give me a definitive answer as to what is different between the two? I thought that everything from the head down was identical, any help is always appreciated.
-Cheers

 

that was my thoughts exactly becuase im pretty sure every thing that hooks up to the engine is in all the same spots. guess we have to wait for a definate answer.

 

Everything is identical between the bottom ends except the pistons. SOHC has a cupped piston top because it runs a lower compression than the DOHC. other than the piston tops they are the exact same except 95's. there is a slight difference in the 95 block that prevents 96-99 top ends to adapt properly.