Questions about first Dyno run
 

I'm heading for my first ever Dyno run this Friday and was curious what (if anything) I should be prepared for.

I've put on about 1500 miles since I completed the total top and bottom rebuild and I thought I would do a Dyno run to see what kind of HP I'm getting.

The car is an 87 3.2 I left pretty much stock except for the GHL muffler, cat bypass, and Steve Wong chip. I thought about bring the stock chip to compare?

I'm sure the guys at the Dyno shop will be able to interpret the results for me but I'm trying to get up to speed on what things Porsche (87 Motronic) specific I need to know and if there's anything I may need to adjust and run again?

I've searched a bit on PP but came up empty, if anyone has advice or links that could help get me up to speed I would appreciate it.

Thanks
Brian

I have a similar setup (GHL 1 in/1 out, Fabspeed euro premuffler, SW chip). There's nothing you can do as far as an "adjustment" on the Motronics, other than to swap chips (i.e. the "adjustments" are mapped into the chips). Several years ago, I performed 6 back-to-back runs on a Mustang dyno (VERY consistent between runs, but "conservative" hp #s.), swapping the chips back & forth between each run, and from my perspective (and everyone else observing), there wasn't a discernable difference between the two chips' graphs. Others' have obtained different results however. I love my SW chip, don't get me wrong, but don't be surprised if there's not a big (or even noticable) difference in the graphs. I do predict that both chips will produce very nice hp & torque curves however... more beneficial than the actual numbers imo (that can vary all over based upon MANY factors). Take it all with a big 'ole grain of salt, but have fun...I know I did!

ps: I did my runs in 4th gear, WOT from around 40 mph up to 110 mph (or so, ...where the dyno shut down). Much of Steve's tuning are in the mappings for partial throttle, so it's certainly not an exact science at all in attempting to 'quantify' these things...or maybe Loren's right after all :)

Relax - the dyno guys are experts and see many cars coming through - They will typically be the ones that "drive" your car during the dyno.

If it's a dynojet 248 have them save the files on your computer drive (zip drives work great for this) send to Steve W to see if he can do any more tweeking.

here's a link to my dyno experience (and commentary)
http://forums.pelicanparts.com/showthread.php?s=&threadid=270504&perpage=20&highl ight=oh%20dyno%20we%20will%20go&pagenumber=1

Can Steve do any additional tweaking without accompanying a/f numbers? Not questioning, just mentioning (for Brian), and curious...

Good information, thanks guys. I'll post the numbers next week.

the dynojet will include AF numbers and at specific rpms

There are a few things that you can do to ensure that your dyno runs are not wasted. Have someone step on your gas pedal while you check that the throttle opens fully at the engine. Use a test light or meter to ensure that the full throttle microswitch is activating after about 3/4 of full throttle. I used to get a lot of dyno runs from guys that were faulty this way and you can tell with with low power output and an AFR curve of a part throttle map. Make sure the dyno you go to has the wideband O2 equipment for measuring AFR. For retuning, have the dyno operator make his full throttle run in third or fourth gear from 2000 to 6800 rpm so a full range AFR sampling can be obtained. If it's a Dynojet, bring a USB memory stick, or a floppy disk, and store the Dynojet run files onto it so you can review them at home on your computer or send them to your tuner. If you're going to do chip swaps, don't bolt the computer down to the floor, and leave the cover on loose. Make sure the two pin 10 California brown wires by the DME are disconnected.

You'd really need the AFR numbers in order to tweak a custom chip to your motor - like tuning a musical instrument, you need tools to tune. Otherwise, with an standard chip, you can only map the chips based on the average of collected samplings. Over time as more samplings are performed, the more tweaked the program gets to match the collected numerical average of a particular engine configuration to maximize power output. As a chip customer, short of a custom remap, you are welcome to free updates to the latest version, so feel free to contact me if you'd like to update your chip to the latest.

Thanks! I think I will very soon. There's not a thing wrong with the one I've been running for several years, but I'm sure you've refined it a bit more since then.

For what it's worth, I have a SW chip in my car, love it. And I haven't even dyno'd the thing and sent the graphs to SW to tinker. One day I'll get around to it.

Love the Chip SW.

Wellborn

Here's the shops website and info on thier Dyno
http://www.idc-solutions.net/ChassisDynoTuning.html

Looks like I'll be getting the A/F numbers Steve mentioned

Here's the numbers, little lower than I had hoped and it seems the graph is a bit choppy. Any thoughts or comments?

http://forums.pelicanparts.com/uploa...1189208719.gif

Your HP number is probably about right, but I'd say your torque is low. It does indeed look choppy and a bit rich.

Here are the A/F numbers. I really know nothing about analyzing these numbers so I'm looking for advise.

The guys running the Dyno seemed to thi9ng it was running rich on the low end and lean on the top end?

http://forums.pelicanparts.com/uploa...1189217682.jpg

Here's the video

http://www.youtube.com/watch?v=gqL0zE1PK40

Uh? Low numbers are rich, higher numbers are lean. 14.5 (ish) is stoich, you probably want to be somewhere around there on an N/A car? So it looks like you're about right lower down and start getting over-rich above 4000 RPM.

Are you sure your O2 sensor is working/connected? Is the TPS switch tripped too early?

The DME goes closed-loop (and starts ignoring the O2 sensor), on full throttle - then it only uses the fuel map entries. Looks like it goes closed-loop too early and that the fuel map is rich, to me. Which makes no sense at all, unless it's a custom chip for a very different motor...

Maybe you have a bad injector dumping too much fuel once the duty cycle gets up there?

Luckily, Steve W is on the thread, so someone who knows what they're talking about will be along soon, I'm sure. :D

You are definitely too rich above 4200 rpm and too lean below 4000 rpm. This will be robbing you of power especially at higher rpm's. The lumpiness looks odd for a stock motor. You really should do a run with your stock chip and get an idea if all of your components are working correctly. If they are, then you will probably need extensive remapping of your new chip.

From the AFR curve, it looks like a dyno run where the WOT switch is not activating. Did you check it previously? Also, do you know how rpm was measured? Peak hp at 6500 doesn't look right. With some dynos such as a Mustang, the operator revs the motor to 4000 rpm, eyeballs the dash tach, and enters that as the rpm calibration - not exactly accurate. I wouldn't be so concerned about the absolute numbers, as different brands of dynos output different numbers. There aren't many people who use DYNOmite dynos, and I think I've only seen one or two dyno runs from that type of dyno, so there's no basis for comparison.

http://forums.pelicanparts.com/uploa...1189272027.jpg

You won't have to do a thing other than have the car warm. They'll tell you to stand back--way back.

This is what you want your a/f ratio to look like when you are done dyno tuning. One run is the motor as a 3.2L with "off the shelf" SW chip, Dansk premuffler and Dansk final muffler (similar mods as to what you have) and the second is the motor as a 3.5L twin-plug with more bells & whistles:

http://forums.pelicanparts.com/uploa...1189273681.gif

Steve will get you there as long as you provide him the data to work with. ;)

Ralph

Wong is right, the WOT switch is not activating. I had checked it after my rebuild this spring and it was fine so I didn't check it before I headed to the Dyno. My bad

As far as the RPM question the operator of the Dynoo had me run the car up to 2500 RPM and hold it for about 10 seconds so I'm guessing he was calibrating the speed of the Dyno to the car? Not sure.

What if anything am I going to notice when the switch gets replaced?
I'll be ordering one from the host tonight.

The WOT switch is adjustable. Try using a hammer and blunt screwdriver and tapping on one of the mounting tabs or the other to get it to activate at the proper throttle position. With a properly operating WOT switch, expect a much flatter AFR curve, 6-8 ft-lbs more torque in the midrange, a smoother power curve and about 15-20 more hp at the top end.