so after finding out that the dohc motor that i wanted to swap into my neon is no good, im thinking about just using the dohc computer and the 3.94 ratio trans in my sohc car. will this benefit me in any way? i've read that you can get good gains from the 3.94 trans on the sohc motor, is this true? and will the computer do me anygood? i've also got a 95 head/cam that i plan on putting on the motor when i do my headgasket, thanks.

 

The 3.94 has shorter gears and will accelerate faster, so yes it is a big gain. I have the 3.55 on a sohc and its blaaaa. The DOHC pcm won't work properly because ti has different timing.

 

alright, thats all i wanted to know. i still need a computer for a sohc mtx since i recently changed my car from atx to mtx. my engine light is on for the torque converter and i can't stand the wierd rev limiter the auto has, thanks for the input.

 

The dohc pcm will work. The dohc pcm will work, but is not "useful," unless you are well modified to take advantage of the higher rev limit. There are plenty of other modifications to consider: air intake, header, under drive pulley, better flowing cylinder head, etc.

 

thats true, if u want, try to swap the head, i mean use the dohc head into the sohc botton, u will gain a lil of hp over there, try to got a high flow filter, headers, good spark plugs and bigger wires, and fuel injectors, with that u car gonna runn really better, i u dont want to swap, do the same thing and u can rev the 7200 but not efective!

 

well i already have some mods done such as a 3.0L intake, cherry bomb turbo muffler, a/c delete(soon power steering also once i put in the manual rack) motor mount inserts and booger shift bushing, probably something else im missing too. i just did another compression test on the dohc and i'm getting good readings now, i dont know if it was my fault in not having the guage in properly or not. comparing the dohc and sohc side-by-side and with the same 3.94 tranny, is the work really worth it not know the condition of the motor? is there actually that much difference between the two? im gonna have to use my harness off my sohc and i dont know if im willing to take the risk if the gain isn't all that big between the motors. as long as i use the 3.94 tranny on my sohc im thinking ill be better off in the end. is this true? thanks.

 

no you will actually loose power due to a lower compression radio...

 

swaping to a dohc vrs sohc not really worth the effort unless you already have the motor which you do... i've driven stock and modded sohc neons and stock and modded dohc engines and yeah the dohc is always going to make a bit more power but a modded sohc can hold its own as long as you have the 3.94 tranny... which you do lol... but yeah the tranny is deff worth it and you have the engine tranny and computer i'd say swap in the dohc you got the parts you'll be happy with it... the 7200 redline in a stock dohc is killer... and there are a lot of newer compact cars that still can't do what a stock dohc can at the track... although a sohc with the 3.94 tranny would also be very close in performance... as for those that say that the stock sohc can't handle the 7200 rpm limit of the dohc pcm... maybe you should take a look at the revlimit of the mopar performance pcm and the AF/x pcm... I know for sure the mopar performance pcm redline is 7400rpm so the sohc not being able to handle the 7200 is just bs... and i know for sure that the mopar performance ecu will work great on a stock sohc...

 

well i tried out the dohc computer today, car made it to about ~7000 and sounded like the valves were floating or something similar to it. im just sketchy on the condition of the dohc and dont know if its worth it to spend hours on end trying to sort wiring problems out to find out the motor is no good, or spend hours putting it in my car with my sohc harness to find out its no good. how can i check this motor over to be almost sure it will be fine. i know about compression and what not, should i check timing to see if it has skipped? just want to know some tests i could run before putting it in, the motor has ~250000 kms on it. if i end up spending to much time i might just forget about it, either way the 3.94 tranny is going in.

 

yeah deff would be a good time to check the timing marks just have to pull the front plastic cover off which i believe requires pulling the front pully off... but seen as the motor is out its a damn good time to change the timing belt and throw a new water pump in it don't cost that much and its piece of mind... other then that if its got good compression and the timing marks are good the motor should be fine unless its got bad bearings but you not going to be able to figure that out unless you pull the oil pan off and start pull main caps and rod caps off and inspecting... you could pull the valve cover off and oil pan off and check for sludge build up and also check for metal shavings in the oil pan if there is no shavings in the oil the bearings should be good... and no sludge or lil sludge build up means the oil has been kept clean and new... just remember that a lil bit of sludge build up is normal... but if your that worried about it start taking the motor apart and do a mild rebuild.... throw new gaskets rings and bearings in it and have a brand new motor... its deff worth the effort, you have no idea it is to put together a motor (even if you go completely stock) and then be able to drive it daily... lol gives you a lil right to brag about your skills... just buy a good repair manual... and have at... and if your worried about not having the money just buy the parts as you can afford and throw the motor in when your done... so do the tranny swap for now and start working on the dohc