4.8L 9psi Tune Advice
09-24-2015, 08:39 PM
#21
Formerly ScreamingL
George, not sure what you mean about 1.0 and 1.1 load.
My AFR in boost is 11.5 commanded, but always stays between 11.4 and 11.7.
Are you suggesting to have transition AFR at 2 and 5 psi? Should AFR at 2psi be about 13.1, and at 5psi 12.3? (or something along those lines?)
My AFR in boost is 11.5 commanded, but always stays between 11.4 and 11.7.
Are you suggesting to have transition AFR at 2 and 5 psi? Should AFR at 2psi be about 13.1, and at 5psi 12.3? (or something along those lines?)
Load is referenced to timing aka g/cyl
You ramp timing out as you ramp fuel in
No reason to be 11.5 at 5 psi
No reason to be weak on timing out of boost
09-24-2015, 08:53 PM
#22
Got it, yes I'll work on that. Timing in cells greater than what I was hitting N/A through the cells I hit at 4.5lbs are at 20 degrees advance. And then I have g/cyl cells greater than what I hit at 4.5lbs are at 14lbs.
I guess ideally it could be a smooth transition from WOT N/A g/cyl timing cells down to my base timing WOT 9psi cells? Vice the 20 degree / 14 degree table tops I got going on right now.
While we're on this subject, how do you all recommend setting PE Enable Map, PE Enable TPS, and using/not using BE?
I guess ideally it could be a smooth transition from WOT N/A g/cyl timing cells down to my base timing WOT 9psi cells? Vice the 20 degree / 14 degree table tops I got going on right now.
While we're on this subject, how do you all recommend setting PE Enable Map, PE Enable TPS, and using/not using BE?
09-24-2015, 09:02 PM
#23
Formerly ScreamingL
Got it, yes I'll work on that. Timing in cells greater than what I was hitting N/A through the cells I hit at 4.5lbs are at 20 degrees advance. And then I have g/cyl cells greater than what I hit at 4.5lbs are at 14lbs.
I guess ideally it could be a smooth transition from WOT N/A g/cyl timing cells down to my base timing WOT 9psi cells? Vice the 20 degree / 14 degree table tops I got going on right now.
While we're on this subject, how do you all recommend setting PE Enable Map, PE Enable TPS, and using/not using BE?
I guess ideally it could be a smooth transition from WOT N/A g/cyl timing cells down to my base timing WOT 9psi cells? Vice the 20 degree / 14 degree table tops I got going on right now.
While we're on this subject, how do you all recommend setting PE Enable Map, PE Enable TPS, and using/not using BE?
BE i set to target afr for each boost level
If 1.20 is 14* for you then line above it would be 16*
Line above 18* line above is 20* all the way till typical NA timing of 28 of around .76 g/cyl
Now ive been more aggressive but that is example for ya
Example i ran 24 psi on e85 and had 20* at 1.2
Line above that was 22* same style ramp to .76 where was 34*
This was on e85.......went 8.65@164
Ran 2 seasons like this
Plugs allowed for this tune up with no knock sensors
09-24-2015, 11:41 PM
#25
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That's Funny because I was just having this discussion yesterday!
Another tuner, claimed he pushed a bone stock LQ4 with 31 degrees of timing on an Engine Dyno.
He Claimed to get 56 HP over stock out of it at 31 degrees with the fueling dialed in. In another sentence below that he says he might have gotten more but the Wide Band on the Dyno wasn't working right...
Although I am not a tuner by any means, I haven't seen many NA combos pushed past that 28-30 mark that lasted very long on pump gas.
Another tuner, claimed he pushed a bone stock LQ4 with 31 degrees of timing on an Engine Dyno.
He Claimed to get 56 HP over stock out of it at 31 degrees with the fueling dialed in. In another sentence below that he says he might have gotten more but the Wide Band on the Dyno wasn't working right...
Although I am not a tuner by any means, I haven't seen many NA combos pushed past that 28-30 mark that lasted very long on pump gas.
Hell early ls1s being 97-98 took 31
My 5.3 in my jeep took 30* and showed power gain
Skeets old 6.0 that held the record for fastest NA 6.0 took 29*
4.8s take timing with having no compression and then adding a cam drops dcr
Another 6.0 i tuned made 480 with 29*
Various dynos used and different tracks to back up
Now newer motors dont take the timing....most ls3s take 26*
My 5.3 in my jeep took 30* and showed power gain
Skeets old 6.0 that held the record for fastest NA 6.0 took 29*
4.8s take timing with having no compression and then adding a cam drops dcr
Another 6.0 i tuned made 480 with 29*
Various dynos used and different tracks to back up
Now newer motors dont take the timing....most ls3s take 26*
Im not doubting anything your saying its just not what I see around here with our fuel, temperature, elevation etc. If your not tuning on a dyno with a load cell (eddy brake) then what timing it takes on a dyno is almost meaningless. I used to have a dynojet with no load cell and sold and now only use a loaded dyno. I could almost always run more timing on the dynojet than the vehicle would actually take on the street or track. I also just dont go off peak numbers either, I look at the average number for the whole run. The dyno I use breaks down the whole run like more engine dyno's and often times a run may make 2-3 more peak hp but less average hp.
There are tons of variables that can affect timing and the timing numbers I am referring to are on stock bottom end, stock compression vehicles. 99% of the ls1 I tuned made the best power at 26-28. Almost every re-tune I do from somewhere I end up making the same power or more with less timing than they came in with and they speed up at the track. Very rarely (probably 1% of the time) do I have to add timing to a vehicle when doing a re-tune.
09-25-2015, 12:18 AM
#26
I do alot of tuning on an engine dyno and the way the load is applied and depending on how the dyno is ran the it can make the tune end up way different than in an actual vehicle. I tuned a Dart 427 on 18psi in a car on the chassis dyno and then a year later had the whole motor and blower setup (intercooler and everything) on the engine dyno and had to re-do all of the tune and made less power. So they are hard to compare sometimes.
I realize there just a tool and the difference between the Engine and Chassis Dyno's can very greatly depending on many factors. IMO It was probably more of a gimmick to sell him self. His statement after the fact seems to support that.
I just find it funny how other's do so little research and buy into the BS there being served.
09-25-2015, 07:50 AM
#27
Formerly ScreamingL
I do alot of tuning on an engine dyno and the way the load is applied and depending on how the dyno is ran the it can make the tune end up way different than in an actual vehicle. I tuned a Dart 427 on 18psi in a car on the chassis dyno and then a year later had the whole motor and blower setup (intercooler and everything) on the engine dyno and had to re-do all of the tune and made less power. So they are hard to compare sometimes.
Thats about what I normally see.
Im not doubting anything your saying its just not what I see around here with our fuel, temperature, elevation etc. If your not tuning on a dyno with a load cell (eddy brake) then what timing it takes on a dyno is almost meaningless. I used to have a dynojet with no load cell and sold and now only use a loaded dyno. I could almost always run more timing on the dynojet than the vehicle would actually take on the street or track. I also just dont go off peak numbers either, I look at the average number for the whole run. The dyno I use breaks down the whole run like more engine dyno's and often times a run may make 2-3 more peak hp but less average hp.
There are tons of variables that can affect timing and the timing numbers I am referring to are on stock bottom end, stock compression vehicles. 99% of the ls1 I tuned made the best power at 26-28. Almost every re-tune I do from somewhere I end up making the same power or more with less timing than they came in with and they speed up at the track. Very rarely (probably 1% of the time) do I have to add timing to a vehicle when doing a re-tune.
Thats about what I normally see.
Im not doubting anything your saying its just not what I see around here with our fuel, temperature, elevation etc. If your not tuning on a dyno with a load cell (eddy brake) then what timing it takes on a dyno is almost meaningless. I used to have a dynojet with no load cell and sold and now only use a loaded dyno. I could almost always run more timing on the dynojet than the vehicle would actually take on the street or track. I also just dont go off peak numbers either, I look at the average number for the whole run. The dyno I use breaks down the whole run like more engine dyno's and often times a run may make 2-3 more peak hp but less average hp.
There are tons of variables that can affect timing and the timing numbers I am referring to are on stock bottom end, stock compression vehicles. 99% of the ls1 I tuned made the best power at 26-28. Almost every re-tune I do from somewhere I end up making the same power or more with less timing than they came in with and they speed up at the track. Very rarely (probably 1% of the time) do I have to add timing to a vehicle when doing a re-tune.
When i stated my jeep took 30 it was on a mustang dyno
I tune aggressively when customer asks by mph but you are right as depends on fuel and elevation
Also earlier motor knocks sensors were notorious for being triggered early and robbing ppl of power
With 26-28* thats about all 10.0+ setups need for Na
Another factor is valve angle and combustion style of head
My 13* heads take less timing then my old 15* stock castings
Now 9.0-9.5 cr motors do take more at times
As for some built combos ive pushed 34* on 110 fuel
And the fastest NA 5.3 took 38* and made over 500 rwhp on racefuel
Few the examples are right in texas
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