[JekylandHyde]

This program is handy if you have the Dynojet files, in raw data:
http://www.dynojet.com/downloads.shtml

Things to remember at the Dyno:

posted by lost27
Just a thread to help people remember what to do at the dyno based of my experiences at the dyno and from talking with other MUCH more experienced people who have dynoed.

1. BRING FLOPPY DISKS TO GET THE DYNO FILES! (very important, you paid for the data it should be yours to keep)

2. Before you even go to the dyno MAKE SURE YOUR IGNITION COMPONANTS ARE GOOD! (theres no sense in wasting money on a dyno if your car is going to be missing or cant hold boost, to ensure that you make good numbers check your plugs, wires, cap, and rotor before you go)

3. ALWAYS dyno in 4th gear. (it is the closest to a 1:1 gear ratio)

4. Start all runs at the same RPM when trying to compare mods( starting a run at a lower RPM will usually make more torque and horsepower since the lower RPM puts more load on the engine and causes the turbo to spool sooner so the graph will be different than one that starts later)

5. Use the STD correction factor with the Runviewer program when trying to compare to other dyno sheets.

6. Pay attention to how much boost you are running and where you're making full boost.

7. Fans are your friend, see if you cant place at least one on the intercooler and one on the radiator. ( i also unplug the temp sensor in the engine bay to make my IC fan run all the time)

8. Monitor your Air Fuel ratio if you can, at least do it for one run, its always good to know how rich/lean you are running.

9. Be nice to they dyno operator; who knows, they may give you one or two more runs than you paid for.

Thats all I can think of off the top of my head, if anyone has anything else to add feel free to share. Be safe and have fun.

posted by lydon
First of all ice does, next to nothing on intakes. Intakes are made of aluminum for a reason...they disapate heat.

3.5 floppies are a must!

dyno numbers should be compared in SAE mod, not uncorrected!
Always tune with the fuel octane, you plan on driving on!
A/F #'s should be verified, prior to making any changes!
always bring a spare set of spark plugs.
Check all lines for vacuum leaks
Verify boost settings!
Allow 30 min cooling time before appointment!
allow 5 min warm-up time prior to baselining!
allow 10-15 minites between runs..after your first TWO baseline runs.
If performance tuning...verify fuel pressure...at idle....and under boost!


Fuel pressure under load should be BSFC + boost level.... if your level drops at peak boost ...you have a fuel supply/ delivery problem!


If I think of more things to check and verify i'll post!

posted by Dmitri
8. Monitor your Air Fuel ratio if you can, at least do it for one run, its always good to know how rich/lean you are running.

The place I went to (Troy's guy) has one person watching AF at all time. If it goes lean, they immediately shut down.

They also replace the stock O2 with a wideband unit (using an adapter place), instead of a stick in the exhaust.

posted by DavidV
Another item to add to the list of things to do at the dyno: Check for boost leaks! Use some soapy water in a sprayer bottle to check for leaks around places like the ICs pipes, BOV, intake piping, turbo, etc.

-- DavidV

posted by David_NA->FI
I work at an AWD Dyno in Houston, Turbochargers.com, and we use the stick probe in the tail pipe, unless someone has their own wideband O2 sensor conneciton.

We usually do pulls in 3rd gear, but sometimes 4th if the gears are really close.
If someone runs 16 or so for more than 1000 rpms and continues to increase in the upper RPMs, 3K+, we shut them down immediately, just stop the rollers and make engine RPMS die down. I don't know about making a run every 10 to 15 minutes... we usually keep the car running if we are tuning an AFC, but if the client wants us to let the car cool we turn the car off and wait a while. Most ppl want hourly tuning, or tune until the HP increase is not that significant (max out). Best thing is to get hourly tuning.

 

[Gandalf]

I thought I'd add this, since it can save time and a mess.

Make very sure your coolant is topped up (not just in the overflow bottle) and that there are no bubbles in your cooling system (I'm not referring to your A2W IC system here, although that's always good too).

You can get away with bubbles for weeks on the road, but the back of the car elevated on a dyno, and not much airspeed flowing through the rad (plus A2W HE shedding warm air up front) the last thing you want is barfing coolant onto the dyno or floor, not to mention the engine bay, and ecu response to heat etc messing up your dyno results and dyno time. The dyno will show up any kinks in your coolant system fast.

And another (seems obvious):
Clean your air filter!

Regarding how long to wait between runs (on my car it takes a couple of runs for the turbo to be good and hot, and by my third pull I get the best results...) it depends on intercooling. Mine has a very quick recovery A2W system, I can do back-to-back pulls only a minute or two apart, and no diminishing returns. But if your IAT's are rising, you may have to wait as long as it takes to cool down, or you will lose power (and on stock intercooling it's a guarantee). In fact, on stock intercooling, or what I consider inadequate intercooling, your best run might be your first run... which might not even be the best run for your turbo!

 

[bionikal]

^ Thanks!

I'm heading out to the dyno on Thursday to get tuned, this list has been helpful!

 

[Texas_Ace]

I could not read past tip 1: BRING FLOPPY DISKS TO GET THE DYNO FILES! (very important, you paid for the data it should be yours to keep).

The thought of trying to use a floppy disk in todays world was too much. Whats amazing is that this is only from 2006. Amazing how far we have come in such a short time. Seems like decades since I used floppys.

 

[Gandalf]

Haha yes, operators can usually now email you the results immediately after, but a memory stick is a good idea so that you can grab all the runs (in case you did like 20 etc)... the idea is correct in spirit.

 

[Texas_Ace]

Haha yes, operators can usually now email you the results immediately after, but a memory stick is a good idea so that you can grab all the runs (in case you did like 20 etc)... the idea is correct in spirit.

Yeah, I always bring a USB drive with me.