Pros and cons of open loop tuning?
04-25-2003, 11:00 AM
#1
LS1Tech Co-Founder
Thread Starter
iTrader: (34)
Pros and cons of open loop tuning? I've got an aftermarket pcm system sitting here that is made specifically for the LS1.
Now, after reading through the manual a few times, I can see that I run it with the MAF and the 02 sensors. Now, if I wanted to I can run it also as an open loop setup.
Problem I can foresee is maxing out unleaded gas too fast, and not hitting my HP goal with say 104 unleaded... I'd like to hit 700rwhp and let's say 140mph first time out (3500 raceweight). I'm not sure what the # might be but with 9:1 compression who knows?
The good features of this controller:
-low impedance drivers
-uses factory crank signal
-uses factory injector/timing signals
-can 'clamp' the maf
-can run open loop in the 'fueller' mode
-pcm controller will cost less than $1000
The bad features???
-not sure if i can plug wideband 02 directly in like FAST
-not sure i can run closed loop and speed density at the same time
-MAF and 02 sensor users would be limited by running unleaded gas unless they want to kill 02 sensors
-might have to splice over 25 wires?
I have a Autronic wideband that I was able to borrow, so I should be able to get a basic tune in the car in time for the North vs South shootout. I know where I need to be as far as tuning and A/F so I have my fingers crossed.
Now, after reading through the manual a few times, I can see that I run it with the MAF and the 02 sensors. Now, if I wanted to I can run it also as an open loop setup.
Problem I can foresee is maxing out unleaded gas too fast, and not hitting my HP goal with say 104 unleaded... I'd like to hit 700rwhp and let's say 140mph first time out (3500 raceweight). I'm not sure what the # might be but with 9:1 compression who knows?
The good features of this controller:
-low impedance drivers
-uses factory crank signal
-uses factory injector/timing signals
-can 'clamp' the maf
-can run open loop in the 'fueller' mode
-pcm controller will cost less than $1000
The bad features???
-not sure if i can plug wideband 02 directly in like FAST
-not sure i can run closed loop and speed density at the same time
-MAF and 02 sensor users would be limited by running unleaded gas unless they want to kill 02 sensors
-might have to splice over 25 wires?
I have a Autronic wideband that I was able to borrow, so I should be able to get a basic tune in the car in time for the North vs South shootout. I know where I need to be as far as tuning and A/F so I have my fingers crossed.
04-25-2003, 08:59 PM
#2
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Re: Pros and cons of open loop tuning? John,
Are some of the wires that need to be spliced the ones for the injectors? I am guessing that they will since it works as an impedance converter...
Are some of the wires that need to be spliced the ones for the injectors? I am guessing that they will since it works as an impedance converter...
04-25-2003, 09:02 PM
#3
Re: Pros and cons of open loop tuning? I among (it sounds) others are interested in this new system.I think you can get good results from open loop but not the best.Is it like a dual mode set up ?It sounds like you got this thing covered , looking foward to hear what it can do! <img src="https://ls1tech.com/threads/images/graemlins/grin.gif" alt="" />
04-27-2003, 03:14 PM
#6
LS1Tech Co-Founder
Thread Starter
iTrader: (34)
Re: Pros and cons of open loop tuning? I'll post purchasing info next week if the company is ready to take orders.
I wonder how much power I can make on 104 unleaded. Sure I can hit over 650rwhp safely, I wonder if I can hit 700rwhp with say an 11.5:1 A/F ratio... That's my goal thru an unlocked converter. It's too early to say which path I will choose, closed loop (traditional) or open loop. I need to see how the piggyback pcm corrects AF in closed loop at WOT... I like the idea (like FAST) of having a target A/F and having the pcm correct +/-25% (like FAST).
This product is not from Racelogic.
It's got dual features yes.
Key issue is whether it diverges from say FAST by not having a provision to self tune off a wideband in speed density or whether it's only capable of tradition closed loop tuning off of the MAF and 02 sensors.
I wonder how much power I can make on 104 unleaded. Sure I can hit over 650rwhp safely, I wonder if I can hit 700rwhp with say an 11.5:1 A/F ratio... That's my goal thru an unlocked converter. It's too early to say which path I will choose, closed loop (traditional) or open loop. I need to see how the piggyback pcm corrects AF in closed loop at WOT... I like the idea (like FAST) of having a target A/F and having the pcm correct +/-25% (like FAST).
This product is not from Racelogic.
It's got dual features yes.
Key issue is whether it diverges from say FAST by not having a provision to self tune off a wideband in speed density or whether it's only capable of tradition closed loop tuning off of the MAF and 02 sensors.
