loudandheard

I just purchased a Carchip which allows me to monitor my speed and various engine parameters. I just can't tell what my car's normal parameters and what I should be monitoring. I was wondering if any one could help me out.

I can monitor RPM, throttle position, engine load, timing advance, coolant temperature, air flow rate, intake air temperature, intake manifold pressure, oxygen sensor output, and voltage. I think there's a few other ones as well.

Here are a few graphs of a recent trip:

Speed


Air Flow


Timing Advance


Intake Manifold Pressure

jturkel

i'm guessing it measures via OBDII.

i have a DashDyno gauge. I usually monitor boost, engine coolant temperature, intake air temperature, and battery voltage. i monitor boost so i know what levels i'm getting..... i monitor engine coolant temperature so i know when my car is relatively warm. i monitor intake air temp so i know when temps are cool if i want to have a spirited run in mexico. and i monitor voltage b/c i've been having voltage problems. i can monitor more things, but choose not to because of a slower refresh rate if i add more things to monitor.

monitor whatever you want to. idk what your mods are, but the ideal things to watch if you are heavily modded like me are boost, intake temp, ignition timing, and wideband O2......but you need a wideband O2 sensor to do that...otherwise, your car will just read off of the stock narrowband which doesnt really do much for you.

Tump43

Hey JT,

I have the same Dash Dyno SPD but can't get it to give me 0-60, 1/4 mile, Hp and Tq numbers. Do I need a laptop to get it to do this?

If you can, please post simple instructions or pm them to me (for some reason, the 100+ page instruction manual just doesn't work for me).

P.S. I monitor: intake air temp, intake manifold pressure, ignition timing & coolant temp.

Thanks,

Lenin

Here are a few points about the car's normal operating parameters.

IAT - watch the relationship between IAT, the outside temps and the Coolant temps. Depending on your mods, 25* - 35* above outside temp at cruising speeds is normal IMHO.

Intake Manifold Pressure - at sea level, you should subtract 14.7 from the raw reading that you get from CarChip. That will give you the true boost level. Most of the time the boost will be below 0 (vacuum). OEM boost on the C32 should be 14.7 or something like that. With a pulley mod, you will see higher readings. Watch the relationship between IAT and Boost.

Timing Advance - I wish I knew about this one myself.

jturkel

hey. i tried doing those things when i first got it, but it wouldnt give me any info. IIRC, you need to put in some information into the dashdyno (gear ratio, which it can determine for you, drag coefficient, curb weight, tire size....etc) before it is capable of determining this information for you. i havent looked into it recently, but i'll look over it again and see if i can figure it out...if i do, i'll post/sent you easy instructions on how to do set it up and do it.

loudandheard

I have a pulley with no tune, so I wanted to make sure that my car is running relatively normal.

I guess I need to do more research and compare various graphs to get an average and hopefully my car's normal specs.

Tump43

Thanks -- when I get a chance I'll look up the necessary C55 info.

mikekuriger

Just curious, why did you buy that if you don't know what to monitor? These devices are only useful during tuning or monitoring a "close to the edge" tune at the track. It wiull not give you any useful information any other time.

~mike~

loudandheard

I recently put on a renntech pulley and wanted to make sure that the car is running normal. I also like the idea that I can monitor my temperatures, read cel's, and clear them as well.

Dingleberry

for the timing, you need to use a line of best fit. was that chart done at full throttle? it looks like timings found during cruising.

loudandheard

Yeah, the graphs were done during regular driving on the highway. The readings were taken every 5 seconds if that helps any. I don't believe I was at full throttle once. All the charts are at from the same time.

mikekuriger

How are you going to determine what is normal? You need to datalog full throttle pulls on a dyno with a wideband A/F guage in order to make that determination. Taking a snapshot of various sensors every 5 seconds will not give you the information you require. You can monitor temperature with the gauge on the dash. You can read and clear CEL's with an inexpensive hand held scanner. A lot of things happen in 5 seconds. Under some circumstances, a lean condition will destroy the engine in less than one second.

Lenin

There is no need to jump on the guy. He is here to learn. I hope he did not pay more than $90 for the CarChip. Before I installed Zeitronix and DashDaq, I used a CarChip to confirm and graph the transmission jerk problem, an intercooler pump failure. I'm sure that there are other good uses for it. It's a good beginning.

loudandheard

It was only $90 and I figured it would give me some knowledge of how my car runs. There have been a lot of unusual things happening to our cars out side of racing.

So there is not point in data logging out side of dyno tuning? I find that hard to believe. Regular driving is where my car gets the most use and I am sure that there is a lot to learn from the car while driving normally.


Yeah, I only paid$ 90 and just like you said I am just learning about the parameters of our cars. I'm sure over time I'll find what I'm looking for. Thanks for the positive response.

mikekuriger

Sorry, I'm not jumping on the guy! My apologies if that's how my tone seems. (I hate writing email!) I'm here to help, that's all.

It's always good to make an effort to monitor the engine, especially when making mods - and a lot of people simply mod and don't bother to see what's going on inside the motor after the mod. I think you're on the right track, however you need the right tool for the job. In this case, you may be using the wrong tool - or using it in the wrong way. that's not a big deal, but we're all on here to help guide you in the right direction.

datalogging during normal driving is absolutely not needed. The "tune" in your computer is only used during open loop driving conditions which is basically full throttle acceleration. During this time, the engine relies solely on the pre-programmed mappings stored in the computer in order to calculate fuel delivery and spark. the sensors on the engine that are used are the MAF/MAP, intake temp, crank position, and RPM. (there may be others but this is basically all the computer needs). During normal driving, the computer is in closed loop mode. During this mode, the computer deviates from the stored maps and makes adjustments based on readings taken from various onboard sensors like the oxygen sensors and knock sensor. This allows the computer to constantly adjust fuel delivery and timing in order to maintain 14.64 AF ratio without pinging (detonation). You have a throttle position sensor that the computer uses to switch from open loop to closed loop.

With a tune, all these parameters can be changed. For example, you can set it so closed loop happens at a different throttle position. You can forse the engine to maintain a different a/f ratio. You can change the maps for fuel and timing if you're changing injectors or cams or making more boost. Changes you make can be fine tuned by monitoring wideband o2 sensors and listening for knock. I use this (http://www.brandsplace.com/0384-jsp0...mpaign=froogle) tool for detecting detonation. If you can hear it in the car, it's probably too late. With this tool, you can hear the tiniest ping long before your pistons have been hammered.

I hope this helps. I think if all you've done is add a pulley, you should be fine. After all, your computer is still maintaining the correct a/f ratio during normal driving. Its full throttle that you should really be concerned about.

~mike~

loudandheard

I really do appreciate your input and apologize for taking it the wrong way. I guess I wasn't too sure why you were telling me that I wasting my time just monitoring normal driving conditions. Your explanation is exactly the kind of info that I was looking for, but now I am more concerned about my car based on what you have said and what has been going on with other members' vehicles.