Cam only guys - looking to see your dyno and a/f ratio, and timing if possible
#1
Cam only guys - looking to see your dyno and a/f ratio, and timing if possible
sup guys -
got cam installed and think the torque under 3500 is off due to incorrect a/f and/or low timing. Mods:
stock 241 heads
FAST 92mm intake and NW tbody
85mm maf and bigger TSP lid to fit
1 7/8 speed engineering headers and 3" off road Y, stock WS6 cat-back (single on the left)
SSRA
Can you please post up your dyno graph if you have a/f displayed? Can you also say where the 02 sensor was placed? in header bung or in tailpipe? In my attached graph, it was in header bung. I believe its about .4 leaner if done in tailpipe.
I also think mid-range torque at peak torque is off slightly from being too rich by a little bit; I think there are gains to be made there while still being safe.
if you have hptuners, I'd love to see your timing table.
got cam installed and think the torque under 3500 is off due to incorrect a/f and/or low timing. Mods:
stock 241 heads
FAST 92mm intake and NW tbody
85mm maf and bigger TSP lid to fit
1 7/8 speed engineering headers and 3" off road Y, stock WS6 cat-back (single on the left)
SSRA
Can you please post up your dyno graph if you have a/f displayed? Can you also say where the 02 sensor was placed? in header bung or in tailpipe? In my attached graph, it was in header bung. I believe its about .4 leaner if done in tailpipe.
I also think mid-range torque at peak torque is off slightly from being too rich by a little bit; I think there are gains to be made there while still being safe.
if you have hptuners, I'd love to see your timing table.
#3
awesome thanks dude.
thats what i wanted to see. i'll try it on dyno and log to make sure. i'm only gonna fudge with the 2000 to 3500 zone as i see you make put in about 3 more degrees. i will try in small steps.
side question - do you adjust a/f ratio by adjusting maf table or PE EQ Ratio? I'm reading conflicting methods.
thats what i wanted to see. i'll try it on dyno and log to make sure. i'm only gonna fudge with the 2000 to 3500 zone as i see you make put in about 3 more degrees. i will try in small steps.
side question - do you adjust a/f ratio by adjusting maf table or PE EQ Ratio? I'm reading conflicting methods.
#4
TECH Fanatic
iTrader: (11)
Ideally, you'd want about 12.7-12.8 before and after peak tq and about 12.5-12.6 at peak torque. Notice the hump at 3800 as you pass through 12.8:1. At 3800 you are good. Lower, raise your VE a little, above lower your VE. Near redline you are really close. Maybe .5% off.
Set your PE table for the target I listed above and dial in your VE to make commanded match WB.
You've left a little power on the table running rich. I'll take a look at my laptop at home this evening and see what I can post up. You'll always get a little weird looking graph near throttle tip in. Should stabilize within a couple hundred rpm. Could you also post your PE and VE tables?
Set your PE table for the target I listed above and dial in your VE to make commanded match WB.
You've left a little power on the table running rich. I'll take a look at my laptop at home this evening and see what I can post up. You'll always get a little weird looking graph near throttle tip in. Should stabilize within a couple hundred rpm. Could you also post your PE and VE tables?
Last edited by Exidous; 06-16-2015 at 07:18 AM.
#5
Launching!
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awesome thanks dude.
thats what i wanted to see. i'll try it on dyno and log to make sure. i'm only gonna fudge with the 2000 to 3500 zone as i see you make put in about 3 more degrees. i will try in small steps.
side question - do you adjust a/f ratio by adjusting maf table or PE EQ Ratio? I'm reading conflicting methods.
thats what i wanted to see. i'll try it on dyno and log to make sure. i'm only gonna fudge with the 2000 to 3500 zone as i see you make put in about 3 more degrees. i will try in small steps.
side question - do you adjust a/f ratio by adjusting maf table or PE EQ Ratio? I'm reading conflicting methods.
Only use the maf table to calibrate the maf. Use the PE EQ ratio after your maf is dialed in to get your commanded. For example 14.7/12.5 = 1.176
If you aren't hitting your commanded, then your maf needs some more tuning to get it dialed in. I'm assuming you're running a maf only tune? If you're blending, I would start with the ve table and then work over on the maf.
#7
hi guys - thanks again.
Main VE and PE tables attached, as well as 3 logs from the highway, showing commanded AFR. one of the logs is 2nd gear WOT and the other 2 are 3rd gear WOT.
My maf table should be dead on as the car was tuned and it idles great (except cold start stalls it out if i try to move before some temp is built up).
Obviously i'm new to this and just trying to take my combo to the level where I think it should be. I think the peak HP is good and in line with other dyno's I've seen, but I feel the torque is not where it should be (even before cam and intake I was making more torque under 3500).
Main VE and PE tables attached, as well as 3 logs from the highway, showing commanded AFR. one of the logs is 2nd gear WOT and the other 2 are 3rd gear WOT.
My maf table should be dead on as the car was tuned and it idles great (except cold start stalls it out if i try to move before some temp is built up).
Obviously i'm new to this and just trying to take my combo to the level where I think it should be. I think the peak HP is good and in line with other dyno's I've seen, but I feel the torque is not where it should be (even before cam and intake I was making more torque under 3500).
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#8
Launching!
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Are you running open loop, or just not capturing fuel trims? Can you send me your tune? I'd like to look at a couple of things. In your first post your afr is all over the place. After I take a look, I'd like to see some pulls with maf disabled and maf only, using some histograms.