Current tune question
05-19-2018, 05:06 PM
#1
Melting Slicks
Thread Starter
Current tune question
I am far from a tuner. I had headers installed and a tune. Picked up 25HP my question is about the AFR is it too lean causing the dip in torque down low, or what? Car runs very well right now.
Last edited by Texan79423; 05-19-2018 at 05:09 PM.
05-21-2018, 01:38 AM
#2
Instructor
I too am just learning to tune, it seems your AFR is pretty high for that type of RPM, my understanding is you want to be around 12.1 AFR at WOT and in the upper RPM range, but hopefully some one more experienced will chime in.
05-21-2018, 09:38 AM
#4
Instructor
Would need lot more info to say anything really...NA or FI? Stock cam? Any mods? 11.5 at WOT is good for forced induction but NA you'll want to be more in the 12.5 range so you're looking pretty good. The torque dip is common with larger cams but depending on fuel he may have had to pull some timing out to avoid knock which could cause it as well.
05-21-2018, 12:47 PM
#5
Melting Slicks
Thread Starter
Gary
This is a 05 LS2 with a BTR stage 2 cam and lifters, stock intake, with 1 7/8 Kook headers. Just installed the headers and got retuned. The shop is really good and does excellent work and I only ask as I am not at all familiar with tuning or what is right or wrong.
It seems to me the down low dip is a lean condition above 13:1 when compared to my past tune. I "think" it needs to go back to the 12.5-12.8 across the run as with the original tune, and maybe a bump in timing later on above 5K. I do not have any of the tables and would not know how to read them anyway
But if I knew anything about tuning then I would not have to be here asking questions. Give me a carb, box of jets, a timing light, and a 1/4 mile time slip and I would be good to go..LOL
Thanks for your input
This is a 05 LS2 with a BTR stage 2 cam and lifters, stock intake, with 1 7/8 Kook headers. Just installed the headers and got retuned. The shop is really good and does excellent work and I only ask as I am not at all familiar with tuning or what is right or wrong.
It seems to me the down low dip is a lean condition above 13:1 when compared to my past tune. I "think" it needs to go back to the 12.5-12.8 across the run as with the original tune, and maybe a bump in timing later on above 5K. I do not have any of the tables and would not know how to read them anyway
But if I knew anything about tuning then I would not have to be here asking questions. Give me a carb, box of jets, a timing light, and a 1/4 mile time slip and I would be good to go..LOL
Thanks for your input
05-21-2018, 04:27 PM
#6
Supporting Vendor
Gary
This is a 05 LS2 with a BTR stage 2 cam and lifters, stock intake, with 1 7/8 Kook headers. Just installed the headers and got retuned. The shop is really good and does excellent work and I only ask as I am not at all familiar with tuning or what is right or wrong.
It seems to me the down low dip is a lean condition above 13:1 when compared to my past tune. I "think" it needs to go back to the 12.5-12.8 across the run as with the original tune, and maybe a bump in timing later on above 5K. I do not have any of the tables and would not know how to read them anyway
But if I knew anything about tuning then I would not have to be here asking questions. Give me a carb, box of jets, a timing light, and a 1/4 mile time slip and I would be good to go..LOL
Thanks for your input
This is a 05 LS2 with a BTR stage 2 cam and lifters, stock intake, with 1 7/8 Kook headers. Just installed the headers and got retuned. The shop is really good and does excellent work and I only ask as I am not at all familiar with tuning or what is right or wrong.
It seems to me the down low dip is a lean condition above 13:1 when compared to my past tune. I "think" it needs to go back to the 12.5-12.8 across the run as with the original tune, and maybe a bump in timing later on above 5K. I do not have any of the tables and would not know how to read them anyway
But if I knew anything about tuning then I would not have to be here asking questions. Give me a carb, box of jets, a timing light, and a 1/4 mile time slip and I would be good to go..LOL
Thanks for your input
Can't hurt to add a little fuel in the low range and see if it helps bring that torque curve back up.
05-24-2018, 02:57 PM
#8
Racer
I usually end up between 0.88 and 0.9 lambda on NA LS setups...so for a 14.1 stoich that is about 12.5 to 12.8:1.
Whats the timing map look like? He could be yanking some timing there for no good reason, or the knock sensors are pulling a bunch of timing where the dip is observed and then slowly ramping it back in.
Whats the timing map look like? He could be yanking some timing there for no good reason, or the knock sensors are pulling a bunch of timing where the dip is observed and then slowly ramping it back in.