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150 hp Neon how-to

150 hp Neon how-to

150 hp Neon how-to

Hello again,

Traded my Miata in on a Neon about a week ago. Hey, don't laugh; they gave me a great trade, considering what the car was worth...

So this leaves me with a little extra money, and two of my friends just told me that they are opening a speed shop.

Gee. What's right about this picture?

So, I'm already thinking about the usual wheels-springs-intake-exhaust customizing routine, when I stumble across the fact that there is a version of the Neon that makes 150 horsepower from the factory. Well, hell, mine only makes 130!

I suppose I could call Daimler-Chrysler, but I thought I'd try Engineering Tips first, since I have a better chance of getting an answer in plain English here.

The questions are:

1) Can anybody tell me what is done to the 2.0 DOHC Dodge Neon engine to boost it's horsepower output from 130 to 150?

2) Will I have to open the block?

3) Can I buy the parts myself?

4) (tangentally) how can I find out what I can do to a Neon without voiding the warranty?


RE: 150 hp Neon how-to

The biggest difference in the SOHC and DOHC 420A is the cam timing. I'm not sure about the compression ratio, but i think the DOHC might be slightly higher. There is a difference in valve overlap of roughly 20 degrees i think. Haven't seen the FSM lately, so i can't give you better numbers. Remember, the computer is tuned to run with the conservative cam.

Best bang for the buck is the Hah Racecraft turbo kit, but that'd void your warranty.

RE: 150 hp Neon how-to



1-Camshaft timing, combustion chamber shape, valves, compression ratio, ECM timing and fuel mapping, to start.

2-YES, plus the biggie, change to the DOHC engine.


4-Pull up the SCCA site and find the email address to your local region and request the phone number or email for their Showroom Stock advisor. He/she will be a good source of performance info, too.

My recommendation for the street- go for suspension mods first and leave the engine alone for a while, it's pretty quick in the right hands as is.  Handling is a LOT different than that Miata.  It will take some time to get YOU up  to speed.

Have fun---Rod

RE: 150 hp Neon how-to

Thanks, Rod.

Did want to make one thing clear, since it may not have been in my original post: it DOES have the 16v engine. This is an '02 Neon, but only the base model. Maybe not a big point, but accuracy does count in here...

And, yes, it does go pretty well, but only when pushed harder than I feel comfortable pushing; I like having that
cushion. The torque is not what I'm used to, though. Might be better off working on that and taking any commensurate gains in HP as an extra. Thoughts on that would be helpful.

As far as handling mods, I've alreaby been to Eibach's web site. Gotta go, now. Will be back with suspension questns later.

Thanks again!

RE: 150 hp Neon how-to

Hello again,

Just reading MoparMatt's questions about horsepower versus torque, and it brought me back here.

Thank you Nick, as well. You're sure the Racecraft will void my warranty? And while I'm at it, is that just a turbocharger or are there other goodies in the "kit"? How much does said kit sell for? Is there a website so I don't have to keep firing these amateur questions at you?

Has everybody gotten the clear idea by now that I'm not an engineer and know very little about cars? Just thought I'd ask.

ANYWAY... Reading through the HP vs LB/FT discussion, I realized that what I do indeed want here is more torque, not more horsepower. I'm sure that an increase in horsepower must bring some torque along with it, but man! These aftermarket parts are expensive! I'd like to be able to get the most for my money.

I have settled on an intake and an exhaust upgrade. There is an aftermarket muffler which is made specifically for the Neon, and brings immediate gains in power. Plus I don't think it has one of those obnoxious resonators in it. Also, I want to put on a cold air intake, but I'll have to make sure that removing the filter box (all two gallons and 3 to 5 pounds of it) won't make Daimler-Chrylser cry "foul!".

I know that an ECU chip would make a big difference, but is there a better mod for the money?


RE: 150 hp Neon how-to

here I go, theorising again-
torque at what RPM?

(does that little beastie have a tach?)
tough to get more torque at lower RPMs without more displacement or forced induction.

to get more kick at low RPM takes mechanical supercharging- turbocharging generally has less grunt at the bottom end than mechanical...

or, go for horsepower at whatever RPM, and just run it in a lower gear?


RE: 150 hp Neon how-to

Torque schmorque, the neon motor is made to spin. both the dohc and the sohc. If you are looking for a performance muffler I would suggest the wrecking yard, the 95 to 99 dohc neons came with a very low restriction muffler that is as good or better than what you will find aftermarket, and a lot cheeper. when you take the muffler off please note that the clamp is part of the muffler so just loosten it and slide it off.
As for the differances between the neon engines, the dohc has 1.37/1.195 and a cr of 9.6 to 1
the sohc has 1.30/1.129 with a cr of 9.8 to 1 there is a company that maes a turbo kit for the neon. it puts out 297 peak HP if I recall right but it will cost you about 3k.

RE: 150 hp Neon how-to

I could have sworn the sohc neon had a CR lower than the dohc so maybe that 9.8 should be an 8.9

RE: 150 hp Neon how-to

i also just recently just bought a 2002 neon, and i also have the sohc engine, and like you i was wondering the same thing about hp and warranties. however i got a special dealer package that came with a very nice body kit toyo tires, crome rims, and custom exhaust. now thats the background on my car, well i have also been lookig around for some parts to give it a little more kick, i have decided to go with a cold air induction kit, for starters, (thought i'd play it safe and not void my warranty). i have been looking around for a racing chip and what i have been told so far is that the dodge computers are fairly difficult to make piggy back chips and such for so they ussualy take longer to come out with eta prolly around a year. my best advice is a short throw if you have a stick,  cold air (k and n f.i.p.k. is fairly decent),tires (my toyo's are great), and springs and struts (cant go wrong with eibach). sorry i couldnt really help more i know thats what you were looking for but hey maybe some of my useless rambling made some sense, plus i had nothing better to do

RE: 150 hp Neon how-to

well i thought i would actually drop by and say something useful for a change if anybody still reads this thing. i was just looking around and i found a very informational site in regards to neon upgrades it is http://www.allpar.com/neon/performance.html hope it helps.

RE: 150 hp Neon how-to

The website for the Hahn Racecraft Neon Turbo is here:

As far as warranty goes, there is the The Magnuson-Moss Warranty Act (15 U.S.C. 2302(C))to protect you.  I have not read the thing in it's entirety, but in a one sentence summary you can't be denied warranty service just because you have a modified vehicle.  (e.g. if you have lowering springs on your car and your ECU goes out, they can't deny you service).  Here's a good website to start with:

That being said, they will most certainly deny warranty service to a Neon with a forced induction kit.  You will be making ~50% more hp than stock and any engine or transmission issues that you might have could be (easily?) traced to the FI kit.

In closing, I completely agree with Evelrod.  I run a '97 Honda Prelude Base model with most of the available bolt on power adders (no FI) and extensive suspension work.  I got *alot* more bang for the buck with the suspension work. My recommedation to new enthusiasts is to always start with the suspension.  


RE: 150 hp Neon how-to

I am not an engineer, but am an Avid neon enthusiast.
I own two sohc neons 98's

First things first, the engine is not a 42oa, in fact it is an in house desighn and not affiliated with mitsubishi at all

Secondly the sohc actually produces 147 crank hp
____- on mine, with a super trapp, underdrive pully, cool air induction, and 205/50 r 15 street tires puts out 152 @ the wheels and runs 15.2-15.4 quarter mile with no weigt redux

check out www.neons.org and read the F.A.Q. and look at the boards racing, and tech "we KNOW where the power is"

RE: 150 hp Neon how-to

Try this  web site, www.allpar.com, ; lots of good mopar info and links

RE: 150 hp Neon how-to

I have never owned a car besides my 2002 Dodge neon. I'm looking to make it worthy of every head to turn. As for looks I have many links for those of you who want some goodies for your interior and body kits you may or may not have even heard of before. My question is Does anybody out there know of, or manufacture a Turbo kit (complete with hoses and intercooler) for the 2002 Neon (Not including ACR or RT models because they are equipped with a different engine then my SXT) because it comes with a 2.0L SOHC that may have darn good torque but it's simply NOT fast enough. If anyone can help me out I'd appretiate any suggestions or links possibly to sites where I may be able to find such a thing. thanks again for the time and concern, sincerely, Brett Bajaquesadilla@ahoo.com

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