[ShouldntBeHere]

Since its off season for racing for us down here in Houston (88* today), I figured I would finish up some stuff I have needed to do before the Fall/Winter race season, one of which was finish my data logger install.....

I am using an old school LM1 with an LMA3 aux box to log all of the data. I will eventually add a fuel pressure transducer so I can also log fuel pressure. For now I am just logging AFR, RPMs and vacuum. Here is a screen shot of a log I just did on the street. This was just a 2nd gear start from about 40 mph. Notice it still has over 1" of vacuum in high gear....air cleaner restriction. I didnt run it all the way through the top of 3rd....only up to about 120 mph or so......

The dip midway through 2nd on the black trace is when i back pedaled it while spinning a bit...

Seems to work well. The only "issue" I have is that the RPM reading is about 70 rpms lower then what my max recall on my auto meter shiftlight says.... The shift light normally shows a max of around 6030rpms at the shift points, this one showing 5960rpms.....Yet at lower RPMs, they read EXACTLY the same so....one of them starts reading fast...about 70 rpms fast not sure which but.....Both of them match my factory tach (cable driven off the dizzy) EXACTLY at 3500 so....calibration wise, they are good....i guess...

So...anyway it should be a valuable tool for dialing this thing in at the strip during race season as I claw my way to 10.49s in -DA air....

Also its cool to plug in the laptop to dial in the mixture screws(the vac channel on the logger matches both of my vacuum gauges within .5hg) without even having to dig up a gauge and hook it up, and I can record the vacuum data anytime its running.

For now its time to cruise for the Summer..... AC was blowing 37* today....:yes: .... Burrrr....

 

[forcd ind]

you can also get a good idea of the stall, and any little dip(bog) with the RPM readout-cool stuff

 

[crazydavey]

reminds me of my EKG...

cool stuff Alan...:thumbsup:

 

[ShouldntBeHere]

Here is the equipment for those interested....

LM1 wideband logger is now discontinued but you can still find them everywhere on the net, new, refurb'd and used. I got mine used for $150...

I tried to find one of these used for over a year and no dice....i finally found a good deal on a new one for $195 shipped.... Make sure you order the interface cable as it doesn't come with the LMA3.

You can log 5 channels of data.....pretty much anything you can get a 0-5v signal from, you can log.....(wheel speed, driveshaft, clutch slippage and ofcourse all the engine vitals).

I have been using this same combo (LM1/LMA3) on my turbo bike since 05 and it has been crucial in keeping it alive and dialing it in for both drag racing and land speed racing..... Can't have a turbo anything without wideband/logging.

I mainly put it in the Vette so I know EXACTLY what its doing while going down the strip...I attach time slip data and DA to the logged runs so I can know exactly what happened on that exact run. Takes the guessing/hoping game out of it....Plus its great for diagnosing problems....:beers:


PS.... I BELIEVE this is the fuel pressure sending unit needed log FP on a low pressure fuel system (ie. carbed and mech pump)

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=734-1025-ND

$83 for that bastard aint cheap but.... I use these SSi pressure sending units on my AMS1000 boost controller on my bike and they are VERY accurate.... Even the 0-100 psi units are accurate to .5%. I have tested them at 1-3 psi before and they are dead on...

I will report back on this thread when I eventually add this fuel pressure addition to my setup and report how well they work.