Aftermarket Gauges and Data Logging
 

Hello,

I have decided I am going to add a few gauges to my car.

What are the differences between the mechanical and electrical gauges?

Currently I have a mechanical VDO boost gauge below the radio in the top empty shelf. I want to change the location of my boost gauge but it appears that running the wiring will be a little tricky. Do electrical boost gauges have the vacume line or just an electrical line?

What gauges do you think are important for a modified engine.
I am thinking a boost, air / fuel and oil pressure. I have room for one more gauge.

How about data logging?
And to complicate matters I want to keep an OEM look.

I have also thought about getting a OBDII system that I can plug into the OBD2 and read a variety of gauges. Similar to the HKS unit Kirk has installed or the Brockway units that the TT guys are running. The problem with this is that a future mod I am working on will require that the OBD2 port is used for something else.

VDO or AEM are the front runners and I think in order to get everything I want AEM will be the way to go. But I like the simple lines of the VDO.

I am open to any other opinions.

Thanks and make it a great weekend.
Gary

been thinking of the same thing for a while now...keep me in the know on what you do.

Gary,

On a boosted car like yours I would say that boost pressure, air/fuel, and exhaust gas temperature (EGT) are the most critical gauges to have. Oil pressure is also VERY good to have on any kind of car, whether boosted or not. I've got an oil pressure gauge in my Honda race car and it has literally saved the engine multiple times. The problem is that the engine burns oil like crazy and I don't always keep on top of it, but the oil pressure gauge lets me know when the oil level gets a quart low as the pressure will start to fluctuate.

One thing that might be nice for a boosted car too is a knock sensor display. This type of display simply connects to one of your stock knock sensors (you have two on the Boxster) or to its own knock sensor. It then displays the level of knock you have in your engine through colored LEDs. The idea is that it's detonation that destroys your engine and if you could only hear it and react fast enough you could lift off the throttle and save your engine. With the knock display you'll SEE when you have bad detonation as a bright, red LED will light up. Then you can lift off the throttle and possibly save yourself a bunch of trouble.

I've personally got the "Knock Link" unit in my Boxster hooked up to its own Bosch knock sensor. The unit is mounted by my hazard light switch, high up on the dash. The LEDs then pretty much function like a shift light for me. If I get any knocking I know it's time to shift quick. I've got it set to ultra-sensitive now, so I see any bad engine noise and just go ahead and shift when I see it.

Attached is a picture of the Knock Link unit I have and here's an article about it:

http://www.turbomagazine.com/tech/0703_turp_knock_sensor_monitor/index.html

I don't know about the $328 price tag though. Seems like a real rip off. I bought mine for my Subaru WRX a few years ago for about $150, including the knock sensor. I got it from TurboXS. I see they don't sell it now, but they do sell a nice alternative that does the same thing:

http://www.turboxs.com/more_info.php?ID=212

Personally I'd worry about boost, A/F, EGT, and oil pressure first. Then if you want to add something like this later it would be nice for ANY modified car. My WRX was modified and I just took the Knock Link with me when I sold the car...

Kirk

The knock link is a good idea. in your non boosted boxster do you see allot of detonation?

I always assumed a healthy engine did not have a detonation problem, but as said in another thread modifying your car you get a PHD in tunning real fast.

The type of gauges you mentioned are the ones I was thinking about (Boost, AF, oil pressure and EGT). I just need to solidify my mounting options to keep the car as "could have come from the factory" look.

I am leaning toward prosport peak and hold in amber
http://prosportgauges.com/premium_series_peak_warning_gauges.aspx

Before I buy them I need to ensure that the bezels can be painted and the illumination can be reduced. I dont want a bunch of bright gauges flashing at me, I want them to blend in and appear OEM.

I may mount the gauges in the slot where the ac control is or in the boost gauges current location in the top storage bin.

What do you guys think of these mounting options?

I wouldn't say that I see detonation. I would hope that I wouldn't have detonation in my car as it's pretty much stock except for a K&N air filter and Gemballa exhaust. What I do see is some activity above about 6,000 RPM when pushing the car at full throttle. The green LEDs jump to yellow to let me know that something is going on. It might be a slight pinging or something like that, but I doubt it's full detonation. I still have the Knock Link set for maximum sensitivity from when I installed it. I really should just turn the sensitivity down. For now though, when I see the lights start bumping up from green to yellow to red I just use that as an indicator that it's probably time for me to shift as the engine is working very hard.

I have decided to go the simple route.
VDO Boost and oil pressure gauges with an amber light installed.


For Air fuel I will get the Turbowerx OSD. It monitors all four O2 sensors at one time in a din size amber display.

I am going to mount the gauges in the top DIN slot, where the AC controls are at and move the AC to a lower section of the center stack.

The gauges lights will be wired into my illumination control so I can control their brightness with the rest of the dash. I will also install a lights off switch. I have a pet peeve about allot of lights flashing at me when I dont want to see them. Even the new radio I am installing has a black out mode. So if I choose my entire center stack except for the ac controls at the very bottom can be dark. Yes I got spoiled when I owned a saab.

1st incarnation of the gauges.

I need to fab a trim piece for the gauges. That will be my project next weekend. The trim for the ac controls was bought last week but it has not arrived yet. I will post pictures again when the trim gets installed.

After driving the car the boost gauge is so much easier to read high in the dash instead in the 3rd cubby hole.
When ever I install the AF display I will mount it where the radio is now.
And the radio will go into the 3rd slot.

As far as date logging I think I am going to go with http://www.autoenginuity.com/index.html


Please forgive the cell phone picture.
Moving the AC control was a bigger PITA than I thought it would be.