SE day at Balanced Performance---dyno and tech

#21

Guys pls make sure that F/A is getting logged on these dyno runs and that you get your data files from BP. Also, take some pics of how they are strapping your cars down, to include the positioning of the rear wheel over the drum, and try to get a feel for how tight your car is being strapped down. Remember that your tires are supposed to be at 36psi. Finally, you should record coolant temps for your runs.

The background. Dynojet is willing to help us figure out why we have problems getting their advertised 1% repeat-ability between dyno systems. But in order to help us, they need details on how the dyno runs were conducted. Some videos of the rear wheel on the drum would be cool too.

The reason for the F/A info is that it can help the group of us to help those people with the engines that test poorly.

#22

Greg, good to see that you’re coming down. How long of a trip is it for you?

RP

#23

[quote=“Patton” post=80006]Greg, good to see that you’re coming down. How long of a trip is it for you?

RP[/quote]

A little over 2 hrs. I figured I’d need a dyno sheet to get my tech sticker for 2015. Pops is probably going to bring his car too.

#24

Great, look forward to seeing you there.

RP

#25

Is there a specific time we are shooting for?

#26

I’m out, engine not ready :frowning: see ya’ll at CMP

#27

Called Jason, waiting on a reply.

Anticipate starting at 9:00am

RP

#28

I’m gonna try to get there sooner than later, so hopefully between 9-10.

#29

It’s best for me to arrive about 11 - that’s my target time. Let me know if I should adjust. See you Saturday.

#30

A bit off topic, but in the preparation for this Saturday I was replacing my oil pan as my last one happened to have an argument with turn 1 back in December (which was definitely not my doing :whistle: ). Anyhow, I’ve noticed that the spare pan that came with my car is also cracked.

Anybody fairly local happen to have a spare oil pan up for grabs? I do have a friend that should be able to weld up the spare pan tomorrow, so it’s not a huge issue if no one has one, but I figure it’d probably be better to swap a pan that hasn’t been cracked.

Thanks,
Alex

#31

John, see you tomorrow. Schedule looks good for arrive as you can.
Start at 9:00.

RP

#32

Is there room for one more? Sumpter

#33

^ I don’t see why not!!

Think Jason would set some scales up for us?

#34

It was good to see/meet everyone.

I was pretty happy with the results of ole faithful.

150hp/150tq now I have to shed some weight!

Thanks for setting it up Robert!

My Pops left crying with his 135/135…:laugh:

#35

Had a great time meeting everyone at the dyno day!
Here are my results 146hp 139tq. The graph showed some interesting things… Lots of oscillations, and the air/fuel does some weird things. Any experts out there have any suggestions? Keep in mind that the car has a street exhaust (cat and muffler).
http://imgur.com/hgfblVH
[URL=http://imgur.com/hgfblVH][/URL]

#36

Looks like an ECU, O2 sensor, afm or tps issue. When the ECU lets go around 5000 it looks ok so it may be getting bad inputs before that. Can u do a stomp test?

#37

It looks like the clock spring in the AFM is too loose allowing the flapper to bounce.

#38

DME should be in open loop on dyno and is therefore doesn’t listen to AFM input. A bad AFM could still be the cause, but I’d guess the bad AFM would cause problems by improperly setting long term fuel trim, not a moving flapper.

As a separate issue, whether or not I’m right or wrong dissing the loose spring theory, one shouldn’t tighten the spring because that hoses the calibration of the AFM. Unless you can be absolutely sure that you got the spring back to where Bosch set it, the AFM becomes a paperweight.

Until about 5k rpm, the engine is running too lean. Impossible to know for sure the cause, but I’d recommend replacing logical candidates below that have an unknown history.

Things to try. Note that each time you swap a part you should kill car power so the DME will reset and also give the car a couple minutes at partial throttle to reset long term fuel trim.

Borrow an AFM from someone else.

Swap DMEs.

Clean or buy new injectors.

Replace coil, dist cap, rotor, plugs, plug wires.

Improve all engine harness electrical connections, and engine ground. Do this by pulling things apart, wire bush the tarnish, and re-assemble with conductive grease.

#39

Thanks guys, I’ll start with Ranger’s list.

Brian - I tried to perform a stomp test which I’ve never done before and didn’t see a light. I thought about it and realized I’ve never seen the check engine light before. I assume the light bulb is out, I’ll check the blinks with a multi-meter and get back to you.

#40

Give this thread a couple days and more good ideas will come from folks. Lots of painfully won experience here.