Surprising Dyno Session Today. LS6's like 22 deg Total Advance.
08-23-2002, 01:56 PM
#21
TECH Senior Member
Join Date: Nov 2001
Posts: 10,341
Likes: 0
Received 0 Likes
on
0 Posts
Re: Surprising Dyno Session Today. LS6's like 22 deg Total Advance. You need to wideband to be sure. I am running 10.8:1 compression with 93 octane and get no KR with 27 degrees advance and 12.5:1 AF across the board.
You could also be getting false knock from vibration as well.
cheers,
Chris
You could also be getting false knock from vibration as well.
cheers,
Chris
08-23-2002, 02:10 PM
#22
TECH Fanatic
Thread Starter
Join Date: Nov 2001
Location: Corona CA
Posts: 1,324
Likes: 0
Received 0 Likes
on
0 Posts
Re: Surprising Dyno Session Today. LS6's like 22 deg Total Advance. I'm going to "wideband" it at two different settings:
22 deg with avg.89 02.
26 deg with avg.89 02.
My stock LS1 liked 02s (never had a wideband) of .87-.89 for peak power. Pulled 339rwhp with a cutout , stock cats, y-pipe, pulley, programming and airlid. Nearly stock.
I'll lean it out 3%, drive 100 mi, go WOT before the pulls, then tie down.
If 26 makes more power than 22, I'll buy more pulls and go 28, otherwise, I'll adjust mixture instead.
22 deg with avg.89 02.
26 deg with avg.89 02.
My stock LS1 liked 02s (never had a wideband) of .87-.89 for peak power. Pulled 339rwhp with a cutout , stock cats, y-pipe, pulley, programming and airlid. Nearly stock.
I'll lean it out 3%, drive 100 mi, go WOT before the pulls, then tie down.
If 26 makes more power than 22, I'll buy more pulls and go 28, otherwise, I'll adjust mixture instead.
08-23-2002, 03:56 PM
#23
TECH Senior Member
Join Date: Nov 2001
Posts: 10,341
Likes: 0
Received 0 Likes
on
0 Posts
Re: Surprising Dyno Session Today. LS6's like 22 deg Total Advance. Forget what the O2's are telling you via ATAP and go only buy what the AF for the wideband looks like.
Try to get the graph smooth at 12.5-12.8:1 AF on the wideband and then play with your timing via LS1Edit. Dynojet only loads about the equiv of a 2800 pounds car so it is safer to run a little richer and a degree or so less timing to account for the added load of real street/track driving.
Chris
Try to get the graph smooth at 12.5-12.8:1 AF on the wideband and then play with your timing via LS1Edit. Dynojet only loads about the equiv of a 2800 pounds car so it is safer to run a little richer and a degree or so less timing to account for the added load of real street/track driving.
Chris
08-23-2002, 04:19 PM
#24
Re: Surprising Dyno Session Today. LS6's like 22 deg Total Advance. FWIW back when i tuned with the MAFT on the open road i tuned using my pos autometer a/f gauge with the sh!tty stock o2's on the maft until i saw between 12.8 and 13.0 on my meter..
that translated to 12.5:1 on a wideband dynojet.
considering the dyno wheel weighs less than my car, giving less load and therefore richer air fuel, i say my STOCK 02's and crappy a/f meter are pretty damn accurate!
maybe im just lucky??
that translated to 12.5:1 on a wideband dynojet.
considering the dyno wheel weighs less than my car, giving less load and therefore richer air fuel, i say my STOCK 02's and crappy a/f meter are pretty damn accurate!
maybe im just lucky??
08-23-2002, 04:22 PM
#25
TECH Fanatic
Thread Starter
Join Date: Nov 2001
Location: Corona CA
Posts: 1,324
Likes: 0
Received 0 Likes
on
0 Posts
Re: Surprising Dyno Session Today. LS6's like 22 deg Total Advance. </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Chris ARE 360:
<strong>Forget what the O2's are telling you via ATAP and go only buy what the AF for the wideband looks like.
Try to get the graph smooth at 12.5-12.8:1 AF on the wideband and then play with your timing via LS1Edit. Dynojet only loads about the equiv of a 2800 pounds car so it is safer to run a little richer and a degree or so less timing to account for the added load of real street/track driving.
Chris</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Correct! I'm going to adjust it close BEFORE showing up for the dyno using the 02's, then fine tune it there. No sense buying more stock pulls.
<strong>Forget what the O2's are telling you via ATAP and go only buy what the AF for the wideband looks like.
Try to get the graph smooth at 12.5-12.8:1 AF on the wideband and then play with your timing via LS1Edit. Dynojet only loads about the equiv of a 2800 pounds car so it is safer to run a little richer and a degree or so less timing to account for the added load of real street/track driving.
Chris</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Correct! I'm going to adjust it close BEFORE showing up for the dyno using the 02's, then fine tune it there. No sense buying more stock pulls.
08-23-2002, 04:32 PM
#26
TECH Resident
Join Date: Jan 2002
Location: USA
Posts: 754
Likes: 0
Received 0 Likes
on
0 Posts
Re: Surprising Dyno Session Today. LS6's like 22 deg Total Advance. </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by John@PACE:
<strong>1) Stock O2 readings DO NOT EQUAL real A/F @ WOT
2) You CAN NOT use PCM "calculated" Torque/RWHP as a comparison ESPECIALLY if you tune the MAF or it's NOT STOCK!
McRat - As ChrisB stated above, you'll probably find different results with playing with fuel/timing on a WB.
TeamZR1 - Are all those power numbers in your spreadsheet dyno generated or are those EASE #'s?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">NOT True, it is if the tuner or mod shop does not know what they are doing.
Who cares what the 02s exact value should be, there has been countless dyno tests and when the powertrain is at its best performance window the 02s read from .880 to .910 mVolts and what is bogus is using a cold 02 which is reading air sitting in a muffler tip.
Where a bogus torque reading computed by the PCM is due to junk ported MAFs and throttle bodies esp when the MAF freq has been stupidly screwed with or with a MAF-T.
Very very few modded cars will need to pull over 11,000 Hz and thus those high priced so called custom MAF or TB is not needed nor proven to be needed,
I just cleaned up a powertrain where the owner bought custom MAF and TB from a vendor I will not mention but one that claims to know it all and the car ran like crap, even with the car being PCM tuned by some so called pro tuner, the knock and HP numbers stunk.
He replaced the ported, polished, super tuned MAF and TB back to stock and ALL the ills went away.
Doing a lousy solder job adding a resistor to fake the PCM as to airflow, yes will bogus Tq numbers but that is done because the tuner has no clue to how to properly tune.
Zero reason for most modded powertrains to need a larger MAF or TB. GM did their homework and the stock MAF, airbridge and TB can more then handle 500 HP.
WB is a marketing tool and maybe its cool hearing the exhaust on a dyno but there is zero proof taking a adaptive learning PCM can be long term tuned with a few runs on a dyno to warrant the price of doing the dyno when valid performance values are computed by the PCM, and do not say the delivered Tq PCM produces are bogus, for I am sure the functions found in a C5 by GM have to be rrue else when active handling, traction control or ABS kicked in the del Tq is an important part of the decisions those functions do.
Those getting invalid delivered torque values, I would assume they love autotap and got their views from it when its proven that scanner produces incorrect DelTq values and has for 2 years I know of.
Many PCM recording I have were produced during cars being on a dyno proved, DelTq and 02 values are correct and simple understanding of proven math and engine functions produce then HP and Tq results.
Anyone just using 02 values to tune is not looking at the right test methods and should understand the PCM does NOT use 02s during PE.
Unless the owner has added supercharger, turbo or lots of NOS, almost all cars with heads, cam, header mods pull less then 450 HP at rear wheels and thus stock MAF, airbridge and TB are fine and will allow correct torque to be computed by PCM.
My computed numbers, Hate to tell you but scanner's do not compute, they report, and my numbers have always compared close to what owner got on a dyno, and are more valid to real world over siting on a dyno drum that does not equal the cars full weight, nor does it produce conditions the car sees when we are on the race track nor does it see all the differnt engine loads seen driving on the streets.
So save the dyno costs and use the money for better purposes.
<strong>1) Stock O2 readings DO NOT EQUAL real A/F @ WOT
2) You CAN NOT use PCM "calculated" Torque/RWHP as a comparison ESPECIALLY if you tune the MAF or it's NOT STOCK!
McRat - As ChrisB stated above, you'll probably find different results with playing with fuel/timing on a WB.
TeamZR1 - Are all those power numbers in your spreadsheet dyno generated or are those EASE #'s?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">NOT True, it is if the tuner or mod shop does not know what they are doing.
Who cares what the 02s exact value should be, there has been countless dyno tests and when the powertrain is at its best performance window the 02s read from .880 to .910 mVolts and what is bogus is using a cold 02 which is reading air sitting in a muffler tip.
Where a bogus torque reading computed by the PCM is due to junk ported MAFs and throttle bodies esp when the MAF freq has been stupidly screwed with or with a MAF-T.
Very very few modded cars will need to pull over 11,000 Hz and thus those high priced so called custom MAF or TB is not needed nor proven to be needed,
I just cleaned up a powertrain where the owner bought custom MAF and TB from a vendor I will not mention but one that claims to know it all and the car ran like crap, even with the car being PCM tuned by some so called pro tuner, the knock and HP numbers stunk.
He replaced the ported, polished, super tuned MAF and TB back to stock and ALL the ills went away.
Doing a lousy solder job adding a resistor to fake the PCM as to airflow, yes will bogus Tq numbers but that is done because the tuner has no clue to how to properly tune.
Zero reason for most modded powertrains to need a larger MAF or TB. GM did their homework and the stock MAF, airbridge and TB can more then handle 500 HP.
WB is a marketing tool and maybe its cool hearing the exhaust on a dyno but there is zero proof taking a adaptive learning PCM can be long term tuned with a few runs on a dyno to warrant the price of doing the dyno when valid performance values are computed by the PCM, and do not say the delivered Tq PCM produces are bogus, for I am sure the functions found in a C5 by GM have to be rrue else when active handling, traction control or ABS kicked in the del Tq is an important part of the decisions those functions do.
Those getting invalid delivered torque values, I would assume they love autotap and got their views from it when its proven that scanner produces incorrect DelTq values and has for 2 years I know of.
Many PCM recording I have were produced during cars being on a dyno proved, DelTq and 02 values are correct and simple understanding of proven math and engine functions produce then HP and Tq results.
Anyone just using 02 values to tune is not looking at the right test methods and should understand the PCM does NOT use 02s during PE.
Unless the owner has added supercharger, turbo or lots of NOS, almost all cars with heads, cam, header mods pull less then 450 HP at rear wheels and thus stock MAF, airbridge and TB are fine and will allow correct torque to be computed by PCM.
My computed numbers, Hate to tell you but scanner's do not compute, they report, and my numbers have always compared close to what owner got on a dyno, and are more valid to real world over siting on a dyno drum that does not equal the cars full weight, nor does it produce conditions the car sees when we are on the race track nor does it see all the differnt engine loads seen driving on the streets.
So save the dyno costs and use the money for better purposes.
