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View Full Version : How long to wait for next dyno after Arrow PCM install?


genVer
05-21-2015, 12:54 AM
Went to get my baseline dyno this afternoon and will be having the Arrow PCM installed tomorrow. How long should I wait for the new controller to learn everything before I go back for a followup dyno test?
G37Sam
05-21-2015, 01:47 AM
The PCM only learns driving habits and torque demands I believe, it does not adjust fuel, ignition or cam timing tables at WOT.
Nine Ball
05-21-2015, 06:45 AM
I would put at least 100 on it, driving it spirited.
BLUETA#1
05-21-2015, 06:53 AM
I am still overheating (240 degrees within 5 laps) at the track so I am going to do back-to back-tests after I change the thermostat. I will run the PCM, swap it out and use the stock ECU for a run. I am praying its the thermostat issue, but I have not changed one of those in 25 years.
1.8t
05-21-2015, 06:58 AM
I dyno'ed my car 1hr and 70 miles after install.
Jack B
05-21-2015, 07:22 AM
You are correct, wot is not affected. LT & ST fuel trims are primarily used during closed loop. Start up and wot are open loop.

That belief that the car gains hp after it "learns" is urban legend.



The PCM only learns driving habits and torque demands I believe, it does not adjust fuel, ignition or cam timing tables at WOT.
01sapphirebob
05-21-2015, 07:26 AM
That belief that the car gains hp after it "learns" is urban legend.

This. The car MAY show a 5hp gain. The purpose of the ARROW PCM is the ability to modify the engine without throwing any CELs and increase the drivability a little bit. I have the arrow PCM for my GEN IV but am waiting to get my differential situation under control first before I drive it.
genVer
05-21-2015, 09:06 AM
Thanks for the response guys, I'll plan to get it back on the dyno again soon then.
Victxv10
05-21-2015, 10:34 AM
This. The car MAY show a 5hp gain. The purpose of the ARROW PCM is the ability to modify the engine without throwing any CELs and increase the drivability a little bit. I have the arrow PCM for my GEN IV but am waiting to get my differential situation under control first before I drive it.

Tony's car picked up 29HP.

http://driveviper.com/forums/threads/8127-Dyno-Tested-Gen-5-Venom-PCM?highlight=arrow
Jack B
05-21-2015, 12:33 PM
A dyno # (5hp is approx 1%) is not that repeatable, especially the mustang.

WOT is fixed, there is no learning in open loop. Any variance is due to the dyno, coolant temp or iat temp.


This. The car MAY show a 5hp gain. The purpose of the ARROW PCM is the ability to modify the engine without throwing any CELs and increase the drivability a little bit. I have the arrow PCM for my GEN IV but am waiting to get my differential situation under control first before I drive it.