as far as the sohc only hitting 7 with the dohc computer most likely has to do with the way different fuel and timing maps for the sohc versus the dohc... but like i said a stock sohc will handle the 7400 redline of the mopar performance...most likely cause its designed just for the sohc.... but hey on a side note did you notice any performance differance with the dohc computer versus the sohc computer?

 

well my car can handle 7k easly, and yeah i can feel i lil biit the diference is not A LOT!! but its better, my car just got some mods as filter, injectors, headers, and stuff like that, and my car rev really good, one time my car get the 7800rpm, my pcm was bad and did not activate the rev limiter,not funny and not good but my car reved it good!

 

the difference i noticed really wasn't that much either, enough that you noticed, just not enough that its worth a lot of money if you dont have one laying around. so what would be holding me car back? sounds like valve float, but maybe not. i have since fixed a wire going into my coil pack and changed the coil pack because of a miss fire, maybe that was my problem? ill have to stick it back in and try this again. with me atx sohc computer when i hit the limiter the car keeps dieing until you let off the gas, no good for burnouts lol, anyways ill put it back in and try it. in the process of changing sub frames now and hooking my bobble strut up.

 

yeah deff could have been the coil holding you back... when your turning that many rpms, you need a pretty healthy coil to keep up with the spark...

 

alright, ill give it another shot when i get off work and see how it works out, its only laying in the other car anyways so it will only take a minute.

 

There is a difference between making noise and making power. The sohc power band ends right around 6800, so your power is on the decline at 7000. 7200 plus is just making noise, especially with the modifications listed. Keep in mid the neon is an economy car with an enhanced model (the dohc). You are attempting to race the baseline form of a car not meant for racing. Take that for what it is worth. The dohc head provides more flow and dual cams for wider range of tuning options. Even on a sohc block, it provides a clear example of why it is better. I ran my neon for over a year, and the drop in compression is not noticeable on the road. Not recommending you run yours that way, but it will not kill your car.

 

he didn't say the extra power was coming from reving that high... all he said was that there was a noticeable difference in power not much but there was a difference... and if reving past 6800 is pointless then way does the mopar performance ecu for the sohc engines redline at 7400?

 

What is the point of a mopar pcm allowing a sohc to rev to 7400? Glad you asked Altima_wb. It is a supporting modification, part of a combination of parts to yield greater performance. It is a pre-tuned engine controller, with a preset rev limit. That does not immediately qualify your car to make power until it stops you. That does make any sense. A rev limiter does not indicate when your engine is no longer making power. It is used to keep the driver from revving too high and causing engine damage.

Such a modification on a sohc car is best maximized when used with head work/porting and an after market camshaft. The more agressive cam profile will take advantage of the new engine controller, making more power for longer.

The OP did not state he was making power in that range, and am not saying he/she did. Your comment about a stock sohc "handling" revving to 7400 is a poor choice of words and information. A stock sohc has no business revving that high, at all. None. It is not making power, the valve train is too poor for it, and it can cause damage. You will not find any dyno chart (how the production of wheel horse power is measured) stating anything to the contrary.

 

the only reason that i put the dohc computer in was to eliminate my check engine light that is looking for a torque converter. i just found it weird that when reved up, it would make it to 7200. i know there is no reason to rev the engine this high, it usually runs out of power after 6000-6300 so there is no need to other than the fact of the way the tranny is geared thats in it now. hopefully the new tranny will fix that.

 

bro a stock neon run better at 6700rpm so close to the rev limiter, i proved that, i had a pcm when the rev limiter was at 6500rpm (iunno why) and my car was totally stock, and shifting at 6700 was better, i improved like 2 and a half car, that a lot in drag racing, and yeah the tranny can fix that!