bypassing the NGC

TN.Frank · Post by **TN.Frank** » Tue Dec 11, 2007 9:49 pm

So someone can wire up a MegaSqurit to their '03-'05 2Gn but can't adapt a 1GN PCM, I'm really not understanding this and I've got an Electronic Tech Degree from DeVry. Granted, it's from '83 but electronics are electronics. If one computer can be used to run the engine, i.e. MegaSqurit then why can't another be used, especially since it's from the same manufacture as the car, i.e. Dodge.
Has anyone looked at what the MAP is looking for with the stock TB in place and if so why hasn't someone come up with a way to trick the NGC system into getting the correct readings with a 55mm TB? It sounds like a lot of Aftermarket people are just being lazy or just don't give a rats butt about us late model 2GN guys.

Post by **racer12306** » Tue Dec 11, 2007 9:55 pm

Megasquirt is much more adaptable than any stock computer. Megasquirt can understand things that a stock computer can't. The crank trigger code between 95-02 computers and 03-05 computers are completely different.

No one has used a 55mm TB yet, so it is unknown about whether or not it will throw the code. Kevo will be finding out soon though.

As Kevo said before, he came up with an idea but it would be costly to implement. I also came up with a similar idea, but it too would be costly.

kevo · Post by **kevo** » Tue Dec 11, 2007 10:03 pm

TN.Frank wrote: Has anyone looked at what the MAP is looking for with the stock TB in place and if so why hasn't someone come up with a way to trick the NGC system into getting the correct readings with a 55mm TB? It sounds like a lot of Aftermarket people are just being lazy or just don't give a rats butt about us late model 2GN guys.

You basically summed up everything about aftermarket vendors and even neon owners in general. They are too lazy and most just wait around for others to make the discoveries.

55mm TB?
soon...

OB · Post by OB » Tue Dec 11, 2007 11:22 pm

Kevo, regarding my post about TB engineering, allow me to clarify what I meant. Companies like MPX don't engineer their TB to relay the correct data from the TPS to the computer. A larger diameter TB has a larger radius and therefore a larger overall throw in relation to the key into the TPS. This causes a signal that is much different than the stock TPS signal that the MAP sensor should be reading for a given throttle position, all other pcm inputs equal. What I mean to say is, IMO a well-engineered product should come with all the proper R&D and as well as the necessary equipment to install and successfully use it. Just because a company knows how to use a CNC machine and program doesn't mean they're engineers. It takes a detailed and thorough approach to fully engineer something properly, not a block of aluminum. See where i'm going with this?

TN.Frank · Post by **TN.Frank** » Wed Dec 12, 2007 6:40 am

I think I've got this figured out, bear with me and see if this makes sense.
For a given Throtlle position with the stock TB the MAP sensor will read a given pressure with the stock intake. There is a ratio of mm of TB to cc's of intake which gives us a given pressure at a given throttle opening. When a person adds a larger TB to the stock intake this ratio is messed up so that for a given TP you'll get more air and thus a higher pressure in the intake which makes the MAP think something is wrong.
Now for the solution. You need to figure out this ratio and install a new intake that'll keep the ratio the same for the TB that you'll be using. That'll keep the pressure the same so the MAP will read the right pressue in the intake for a given TP.
Does that sound about right?

kevo · Post by **kevo** » Wed Dec 12, 2007 7:37 am

OB wrote:Kevo, regarding my post about TB engineering, allow me to clarify what I meant. Companies like MPX don't engineer their TB to relay the correct data from the TPS to the computer. A larger diameter TB has a larger radius and therefore a larger overall throw in relation to the key into the TPS. This causes a signal that is much different than the stock TPS signal that the MAP sensor should be reading for a given throttle position, all other pcm inputs equal. What I mean to say is, IMO a well-engineered product should come with all the proper R&D and as well as the necessary equipment to install and successfully use it. Just because a company knows how to use a CNC machine and program doesn't mean they're engineers. It takes a detailed and thorough approach to fully engineer something properly, not a block of aluminum. See where i'm going with this?

No, i really don't see where you are going with this. A throttle body is just a throttle body. I do agree that Lots of blame needs to be put on guys like MPX and Lorenzo for simply not using their brains. I believe these units should not be sold to NGC owners without a fair warning of the consequences. I have heard from Lorenzo, he states that he will give a free throttle body for anyone that comes up with a solution.

With that being said, I have thought of just about everything you can imagine. I even thought of disassembling a 60mm TB, putting a torch to the end of the blade shaft and bending it counterclockwise just a bit to trick the TPS. Physically there is nothing that can be done besides going off and using a smaller throttle body.

Electronically there is something that can be done. This would however, involve complex hardware to control the voltage feedback of the TPS on the fly.

TN.Frank wrote:I think I've got this figured out, bear with me and see if this makes sense.
For a given Throtlle position with the stock TB the MAP sensor will read a given pressure with the stock intake. There is a ratio of mm of TB to cc's of intake which gives us a given pressure at a given throttle opening. When a person adds a larger TB to the stock intake this ratio is messed up so that for a given TP you'll get more air and thus a higher pressure in the intake which makes the MAP think something is wrong.
Now for the solution. You need to figure out this ratio and install a new intake that'll keep the ratio the same for the TB that you'll be using. That'll keep the pressure the same so the MAP will read the right pressue in the intake for a given TP.
Does that sound about right?

you are better off reading these
http://en.wikipedia.org/wiki/MAP_sensor
http://en.wikipedia.org/wiki/Throttle_position_sensor

esteinmaier · Post by **esteinmaier** » Wed Dec 12, 2007 9:40 am

The solution would be to change the shape of the rounded cable guide thingy (Don't know what it's called) that rotates the throttle plate. If you were to reduce the throw at low to mid throttle positions, the MAP sensor would see more vacuum, thus in line with the allowances programmed into the computer. The hard part is keeping the shape so that it still opens fully at WOT.

BTW, us turbo guys have the same problem. Having a turbo makes it expecially easy to run 0 MAP at partial throttle. Same code, same result. Which is why I'm surprised Hahn can get away with selling the portfueler as "no check engine lights" on their 03-05 kit.

Once again (Shameless plug) this is why our turbo kit is better than Hahn's. Since we don't have to rely on the stock computer's ability to relate TPS to MAP, that problem just disappears.

kevo · Post by **kevo** » Wed Dec 12, 2007 10:49 am

esteinmaier wrote:The solution would be to change the shape of the rounded cable guide thingy (Don't know what it's called) that rotates the throttle plate. If you were to reduce the throw at low to mid throttle positions, the MAP sensor would see more vacuum, thus in line with the allowances programmed into the computer. The hard part is keeping the shape so that it still opens fully at WOT.

BTW, us turbo guys have the same problem. Having a turbo makes it expecially easy to run 0 MAP at partial throttle. Same code, same result. Which is why I'm surprised Hahn can get away with selling the portfueler as "no check engine lights" on their 03-05 kit.

Once again (Shameless plug) this is why our turbo kit is better than Hahn's. Since we don't have to rely on the stock computer's ability to relate TPS to MAP, that problem just disappears.

Im not sure what that rounded thingy is. If you mean the area inside of the TPS then that wouldnt work either. the ECU will just learn the new parameters.

Your issue with the turbo spooling is the same issue SRT guys have; PTB or partial throttle boost. I believe there is a fix for turbo guys on srtforums though. The same can't be said for N/A neon owners.

esteinmaier · Post by **esteinmaier** » Wed Dec 12, 2007 11:38 am

Let me see if I can explain it better... It's like a guide on the outside of the TB that the cable attaches to, and when the cable is retracted, it turns this rounded thing.

But now that I put more thought into it, that wouldn't work either, as the TP signal would still be non-proportionate with the airflow as expected. Damn. Looks like an electronic device would be the only way around it.

All you electronic engineer types: Anyone know of a device that can take an input and reduce the output based on certain parameters? Such as lower voltage in a specified range but not filter voltages higher? Of course, it would have to be soft-knee, gradually feeding more of the voltage proportionate to the original signal as it rises.

TN.Frank · Post by **TN.Frank** » Wed Dec 12, 2007 11:40 am

So why not just come up with a new MAP sensor that's recurved(for lack of a better term) to the larger TB? I'm sure as a sensor it's simply a matter of making the resistance different so it'll send a different reading to the computer to show that all is well in NGC world with the larger TB.

kevo · Post by **kevo** » Wed Dec 12, 2007 6:04 pm

TN.Frank wrote:So why not just come up with a new MAP sensor that's recurved(for lack of a better term) to the larger TB? I'm sure as a sensor it's simply a matter of making the resistance different so it'll send a different reading to the computer to show that all is well in NGC world with the larger TB.

"clamped" map sensors have been tried before. I believe moxhair did.

I have an idea to adjust the TPS values by percentage using a basic max 232 chip. http://www.datasheetcatalog.com/datashe ... X232.shtml

Its just a thought i have in my head right now but in theory, that and a small pic chip should be able to hold plenty of code to adjust the TPS. I'm still not going to tinker with it though, I'm really trying to focus my time on my 55mm project.

turbodudey · Post by **turbodudey** » Wed Dec 12, 2007 6:58 pm

kevo wrote:I have an idea to adjust the TPS values by percentage using a basic max 232 chip. http://www.datasheetcatalog.com/datashe ... X232.shtml

Its just a thought i have in my head right now but in theory, that and a small pic chip should be able to hold plenty of code to adjust the TPS. I'm still not going to tinker with it though, I'm really trying to focus my time on my 55mm project.

Not really sure what you would do with a dual channel serial comm chip (like the one you posted the link to). Sure, there is an op amp in that chip that so that it can convert a standard RS232 signal level to TTL levels, but all you really need is the op amp itself. No need to get a serial comm controller when you wouldn't be using 98% of the logic in the chip.

This is all you need: http://en.wikipedia.org/wiki/Operational_amplifier

A simple op amp circuit with a pot to adjust the gain should be all that's required to tune the output voltage of the TPS to an acceptable level. Or if you want to go super fancy, you could use a non linear op amp to accomodate the highly non linear mass flow rate at low throttle positions (probably not necessary though).

kevo · Post by **kevo** » Wed Dec 12, 2007 7:31 pm

turbodudey wrote:
kevo wrote:I have an idea to adjust the TPS values by percentage using a basic max 232 chip. http://www.datasheetcatalog.com/datashe ... X232.shtml

Its just a thought i have in my head right now but in theory, that and a small pic chip should be able to hold plenty of code to adjust the TPS. I'm still not going to tinker with it though, I'm really trying to focus my time on my 55mm project.
Not really sure what you would do with a dual channel serial comm chip (like the one you posted the link to). Sure, there is an op amp in that chip that so that it can convert a standard RS232 signal level to TTL levels, but all you really need is the op amp itself. No need to get a serial comm controller when you wouldn't be using 98% of the logic in the chip.

This is all you need: http://en.wikipedia.org/wiki/Operational_amplifier

A simple op amp circuit with a pot to adjust the gain should be all that's required to tune the output voltage of the TPS to an acceptable level. Or if you want to go super fancy, you could use a non linear op amp to accomodate the highly non linear mass flow rate at low throttle positions (probably not necessary though).

NGC uses SEP to comms with the sensors thats why i first thought of using a 232 and its amp circuit. On the other hand, your idea is much simpler and would likely work with a bit of first hand experimentation. I was thinking along the lines of having another chip control the amplification, not using a pot to manually adjust the gain.

turbodudey · Post by **turbodudey** » Wed Dec 12, 2007 10:04 pm

Right on.

TN.Frank · Post by **TN.Frank** » Thu Dec 13, 2007 9:28 am

It's starting to sound like throwing the NGC system in the trash and getting a MegaSqurit or other 'puter system installed is about the only option we have for now. At least until some programers get off their lazy butts and crack the NGC code and come up with some mods for it. Computer controled cars SUCK!

Post by **occasional demons** » Thu Dec 13, 2007 10:16 am

TN.Frank wrote:I think I've got this figured out, bear with me and see if this makes sense.
For a given Throtlle position with the stock TB the MAP sensor will read a given pressure with the stock intake. There is a ratio of mm of TB to cc's of intake which gives us a given pressure at a given throttle opening. When a person adds a larger TB to the stock intake this ratio is messed up so that for a given TP you'll get more air and thus a higher pressure in the intake which makes the MAP think something is wrong.
Now for the solution. You need to figure out this ratio and install a new intake that'll keep the ratio the same for the TB that you'll be using. That'll keep the pressure the same so the MAP will read the right pressue in the intake for a given TP.
Does that sound about right?

The problem with that is that the pressure in the manifold isn't a constant value for the TB angle. RPM and engine load will have a huge influence on MAP/vacuum. I would almost bet that there is more vacuum at 6800 rpm @75% throttle opening than at 1000 RPM @ 75% throttle opening. Just an example. Boosted engines are a bit different but the turbo wouldn't be producing the same boost for the given example either.

CASPERAMC · Post by **CASPERAMC** » Thu Dec 13, 2007 11:07 am

well i know this thread has sort of veered off the ngc into throttle bodies, but i just wanna throw in that with an automatic 04 neon (stck computer) with just cai, srt exhaust, plugs wires, screamin demon coil pack, mm, and prob soemthing im forgetting, i put down 126.1 whp im not saying that thats a lot, but its 15 over stock with an auto, and those minor mods, so maybe the mgc doesnt limit power. now im squirted, but i dont know what im putting down. it is more though

OlyR/T · Post by **OlyR/T** » Thu Dec 13, 2007 11:22 am

What I understand about the NGC is that no matter what mods you put on your car it will still have the same A/F ratio and RPM range. It means that even if you put a new cam in your car it will run off the stock RPM range set by the NGC and a beefed up fuel system will just have to suck in more air to get the right readings. It doens't cancel out mods it just limits how they can modify your car. Have I been told incorrectly or am I right on with this?

03blackrt · Post by **03blackrt** » Thu Dec 13, 2007 11:23 am

Like esteinmaier said, just change the throttle shaft cam. Make it so it flows the same amount as stock for the low throttle positions, then make it snap open at the last few degrees of rotation. Wouldn't be hard to do at all.

All the electronic stuff, thats just way over thinking it IMO.

TN.Frank · Post by **TN.Frank** » Thu Dec 13, 2007 11:24 am

CASPERAMC wrote:well i know this thread has sort of veered off the ngc into throttle bodies, but i just wanna throw in that with an automatic 04 neon (stck computer) with just cai, srt exhaust, plugs wires, screamin demon coil pack, mm, and prob soemthing im forgetting, i put down 126.1 whp im not saying that thats a lot, but its 15 over stock with an auto, and those minor mods, so maybe the mgc doesnt limit power. now im squirted, but i dont know what im putting down. it is more though

Exhaust and CAI will add HP but plug wires and coil pack won't really add any HP, just help you not lose any. What is an MM by the way? Also, isn't the 2.0L suppose to be more like 104 WHP, so you're about 22 HP up over stock, not to shabby if you do a percentage deal, that's over 20% over stock.
I'm going to add a header and that Magnaflow free flow cat I picked up from a guy here, add a Under Drive pully then think about getting a LSD diff and 3.94 gears and a decent clutch set-up then call it a day on engine/trans mods. Not going to mess with the intake side until they get all this stuff figured out or until I get a MegaSqurit installed since I don't want to throw a CEL all the dang time. I'll probably get better Anti-Sway bars and Strut Bars to stiffent things up and I'd like new Tires and Rims and maybe springs to lower the car a inch or so. Then I think I'll have done pretty much all I can do other then add a turbo and I don't have the bucks for that.
Keep us updated on the 55mm TB install Kevo, I'd like to see how it turns out.

jckevns · Post by **jckevns** » Thu Dec 13, 2007 11:34 am

mm = motor mount i believe

TN.Frank · Post by **TN.Frank** » Thu Dec 13, 2007 11:44 am

jckevns wrote:mm = motor mount i believe

Ahh, thanks, that makes sense. I've got my Race MM's in and I'm waiting for the Transaxle ones to come in and that'll take care of my mounts.
I'm finding out that this car has more Aftermarket then my '04 Dodge Ram 3.7L but less then a lot of other "Tuner" cars on the market. I'll be glad when the market catches up so us '03-'05 guys can do more 'puter tuning to em'.

turbodudey · Post by **turbodudey** » Thu Dec 13, 2007 1:31 pm

03blackrt wrote:Like esteinmaier said, just change the throttle shaft cam. Make it so it flows the same amount as stock for the low throttle positions, then make it snap open at the last few degrees of rotation. Wouldn't be hard to do at all.

All the electronic stuff, thats just way over thinking it IMO.

Changing the throttle cam won't help. If you read a couple posts down, esteinmaier corrects himself.

Changing the thottle cam only affects the relationship between throttle blade angle and the throttle pedal. It won't have any affect at all on the relationship between throttle blade angle and TPS voltage.

The only mechanical solution to the TPS/MAP correlation issue would be to rig up some sort of cam between the throttle and TPS. So that one degree of throttle rotation would produce more than one degree of TPS rotation. Electrically altering the TPS signal would probably be simpler...

Post by **racer12306** » Thu Dec 13, 2007 1:44 pm

OlyR/T wrote:What I understand about the NGC is that no matter what mods you put on your car it will still have the same A/F ratio and RPM range. It means that even if you put a new cam in your car it will run off the stock RPM range set by the NGC and a beefed up fuel system will just have to suck in more air to get the right readings. It doens't cancel out mods it just limits how they can modify your car. Have I been told incorrectly or am I right on with this?

Unless you change the computer in any neon, NGC or not, it will stick to the same rpm range.

It keeps afr's right where they should be. So if you add more air then it adds more fuel, which is the whole point in making power.

NGC is a good thing and it doesn't matter what anyone here says about it. Sure it's frustrating sometimes, but its still good. Megasquirt would help a non-NGC neon just as much. OEM computers are always far from ideal. They can't specifically tune a car for every possible condition so they have to set the computer so it will safely run in all conditions.

Kevin_GP · Post by **Kevin_GP** » Thu Dec 13, 2007 2:13 pm

racer12306 wrote:
OlyR/T wrote:What I understand about the NGC is that no matter what mods you put on your car it will still have the same A/F ratio and RPM range. It means that even if you put a new cam in your car it will run off the stock RPM range set by the NGC and a beefed up fuel system will just have to suck in more air to get the right readings. It doens't cancel out mods it just limits how they can modify your car. Have I been told incorrectly or am I right on with this?
Unless you change the computer in any neon, NGC or not, it will stick to the same rpm range.

It keeps afr's right where they should be. So if you add more air then it adds more fuel, which is the whole point in making power.

NGC is a good thing and it doesn't matter what anyone here says about it. Sure it's frustrating sometimes, but its still good. Megasquirt would help a non-NGC neon just as much. OEM computers are always far from ideal. They can't specifically tune a car for every possible condition so they have to set the computer so it will safely run in all conditions.

Yes, tuning a turbo with a 02 computer sucked, maybe not as much as NGC but it was still a stock computer with tons of limitations. The thing pulled timing randomly, knocked at weird times, and ran better with the CEL on for some reason. If anyone is serious about modifying there car, you will soon realize that the stock ecu is the problem in 2gns.

I don't agree with everyone saying MS is the answer for everyone, its the answer for the select few who take the time to get over the huge learning curve. The few of us who have MS on our neons think its easy and the best, but when I first got MS it was the most frustrating thing I have ever dealt with. I don't think anyone will ever make a programmer that will be useful to NGC cars, so everyones stuck between a rock and a hard place.

TN.Frank · Post by **TN.Frank** » Fri Dec 14, 2007 10:52 am

So what can a person do to the intake side of the engine to get more air into it other then adding a CAI or the like? Is there any aftermarket intake manifolds that'll work with the stock TB that'll allow it to feed more air to the enging without throwing a CEL? Since it seems we're pretty much stuck with the stock TB, intake manifold would be the only other option were they're be a restriction in air flow.
On the exhaust side you can add a header and a free flow cat as long as both O2 sensors are hooked up you shouldn't throw a CEL, right?
How about the Under Drive Pullies on the market, will you get a CEL because the Alt. isn't being turned as fast so it's not putting out the current it normal would. Just what and what will not make the NGC throw a code and make the CEL come on?

Post by **racer12306** » Fri Dec 14, 2007 1:40 pm

UDP's are good. The only cars that throw a code because of an UDP is 02 r/t's because it senses an over rev situation i believe. and it's only at >5000rpm. but that goes away quickly.

esteinmaier · Post by **esteinmaier** » Fri Dec 14, 2007 2:02 pm

Has anyone tried putting a slight restriction on the MAP sensor? I'm not sure if the code is triggering on the sudden TPS changes or sustained partial throttle, but it would be worth a try. And it would be a mechanical solution, so those that aren't good with wires could do it without being intimidated.

kevo · Post by **kevo** » Fri Dec 14, 2007 2:41 pm

esteinmaier wrote:Has anyone tried putting a slight restriction on the MAP sensor? I'm not sure if the code is triggering on the sudden TPS changes or sustained partial throttle, but it would be worth a try. And it would be a mechanical solution, so those that aren't good with wires could do it without being intimidated.

hmm, i dont see how that would be any different from a map clamp.

Kevin_GP · Post by **Kevin_GP** » Fri Dec 14, 2007 2:47 pm

racer12306 wrote:UDP's are good. The only cars that throw a code because of an UDP is 02 r/t's because it senses an over rev situation i believe. and it's only at >5000rpm. but that goes away quickly.

It was at about 4,000 rpm for me, it would trigger on the highway at around 85ish mph if i remember correctly. Its annoying because if you sustain those speeds the stupid cel will keep blinking and making a noise.