Problem with delievered torque

[cmitchell17]

I have never figured out why my deleivered torque is so low. I barely see over 300ft.lbs.

I know with a modded engine without dialing in the maf and VE it will not be accurate, but with a stock 5.3, just exhuast, why would it not read more like 330+ especially with a little added timing.

I can compare my stock tune deleivered torque with my modififed tune and my tune makes about 10-30ft.lbs more torque, but thats at part throttle.
At wot its the its a little more but about the same.

It seems like gm tested these engines under a lot of conditions and monitored the torque they made. So what conditions do I have that I am not making the correct torque.
However, it makes good torque at low rpms according to the deleivered torque. It makes the same torque at 1500-2000rpms as it does at 4000.

Anybody else with a 5.3, what is your delivered torque?

I think i could also control my shift pressures a little better with more torque reading at WOT.

I have cleaned my maf with maf cleaner.

Also while im asking a question what does it mean when your logging TCC mode and it says, TCC apply enabled, or TCC coast? Mine likes locking up when giving it more gas to go up a hill, and then it starts lugging untill you give it more then it finnaly releases. It does this with stock settings too.

[joecar]

Also while im asking a question what does it mean when your logging TCC mode and it says, TCC apply enabled, or TCC coast? Mine likes locking up when giving it more gas to go up a hill, and then it starts lugging untill you give it more then it finnaly releases. It does this with stock settings too.This is what it is believed to mean:

Off = "Off" -> A-B and I-J
App = "Applying" -> B-C-D
AppEn = "Apply Enabled" -> D-E
Lock = "Locked" -> F-G
Coast = "Coasting" -> H (similar to D-E, see note below)
Rel = "Releasing" -> H-I
http://img521.imageshack.us/img521/6403/tccmodebg4.png

note:
H-I might also have an intermediate stage so it may look like the mirror of B-C-D-E;
in this case, then "Coast" would probably be the flat part.

Diagram is from post #5 of this thread: showthread.php?t=4304 (http://forum.efilive.com/showthread.php?t=4304)

[cmitchell17]

Thanks joecar for the input.

I just don't see why my converter always locks when I give it more throttle and the speed stays the same or decreases speed. I can't really figure out if its in 4th TCC unlock when I hit the hills or what. It seems that ways and the logs look that way.

I wish the 4l60 had a few more gears like a gear between 3rd and 4th to cruise with the TCC unlocked, and definately a gear between 1st and 2nd.

[cmitchell17]

I found another 5.3 log out of a yukon. And I see about 292lb. feet of torque at about 4000rpms.

But I remember a log from a 6.0 that showed about 350-360lbfeet of torque.:nixweiss:

[southern]

I just looked at some logs I had on my pc and the highest I could find was 305 but I will have to log my current tune and see

[Gordy M]

A log from my LQ9 6.0L shows 398 in second gear under acceleration. HTH. I could not find any files from my 5.3L Yukon.

[cmitchell17]

I logged a LQ4 and I think I remember it showing around 350-360. Thats what its rated for I think.

But I wonder why the 5.3 is only making 300.

Was the LQ9 running the stock timing.

[cmitchell17]

What are yalls IAT.

I think that has a effect on it. I think I saw higher in the winter.

If you have no internal engine work stock heads cam intake, I would not see why this would not be accurate.

I wonder if the delievered transmission torque is diffrent from the engine torque.

[southern]

Well I did a little tuning tonight just messing around waiting on my wideband and the highest I saw was 316 at I think 86*

[Gordy M]

Was the LQ9 running the stock timing.
The engine was stock but I just installed a trans tune. RPM was 4019, IAT was 95, TPS was 100, MAF was 214 and temps were 195. HTH

[southern]

hey cmitchell17 I know that after I did my auto VE that my torque jumped up to the 33x range from the normal 30x-31x I usually see.

[cmitchell17]

Whats your setup?

Are you stock?

If you are stock or close to stock you mind sharing what you got out of the Auto ve, mabey I could try a little of you ve table I wouldnt see why it would be diffrent if we both got stock cams heads.

[southern]

Here you go here is my tune as far as the low timing goes I am running on 87 with no problems. Look at the VE table compared to the factory one it is not perfect for my truck just yet but it is getting close. And the highest I found was 343 and but mostly in the 33x range. Yes it is factory except for a magnaflow and the tuning.

[cmitchell17]

I thought your ve table looked wierd and was a little too much.
So I took a ve table from a 2005 5.3 and it was just a little diffrent from yours.

So I guess GM might have screwed up with the ve tables on the older 5.3s?
I dont think there were any diffrences in the motors. Unless they changed the cam but would that cause the ve to change by around 10% in some places especially in peak torque.

[southern]

when was it that they swapped to the new heads, cam, and flat top pistons? Wasnt that in 05? If so then ya I would think the VE table would be off quite a bit compared to the early ones.

[cmitchell17]

I thought the LM7 was unchanged through the years, in 05 electric fans went on and the LM7 was rated at 295hp instead of 285. The L33 had diffrent heads which put the compression at 9.9 to 1 instead of 9.6 the L33 also had a bigger cam and an alumimnum block.

The spark table for the 05+ are different. The 01 ve table is diffrent from my 00 and im pretty sure nothing was changed through these years.

[southern]

I was not sure when they did or in which ones they changed them in. When I get to fealing better I will finish me VE and post it up for you but only changing that my mid-range is a lot better now and i have to be care full to not break loose on wet roads now as well. But i need to finish it and jump back on my timing tables.

[cmitchell17]

Mabey if we could find some timing tables people have used with even 5.3 with exhaust. I dont think headers and exhaust would change that much. Its just that every one that tunes on a dyno would probably have a cam or heads and that would work for our timing.

Im starting to doubt the optimal timing table as the best timing after reading so much about how little timing is needed on these gen III heads.

I wouldnt see where timing would be diffrent with headers besides the increased ve headers would give you.

[southern]

Well the best timing table would be built, compared to the one that gm puts on all the trucks. But that would be a major pita to do ( I would think. ) I agree most people with a dyno tune are usually well into modding them. So have you tried out the new VE table yet? I checked mine last night and came up with the bins ranging from .98 to 1.02 I think and the target area is +/-.01 from 1.00 so it should be pretty close.

[cmitchell17]

I just updated to a 2002 os which I think fixed my trans shifiting and made it smoother. But my delievered torque hasnt changed.

[southern]

did you change you PE table? Cause mine is still showing in the 33x range

[cmitchell17]

No I still have my PE like it was at about 12.4-12.8AFR. What does your torque drop off to at high rpms?

Are you logging deleivered trans torque or deleivered engine torque?

I dont no if that makes a diffrence or not.

Have you done some tuning on your spark yet? Ive always had knock when the TC is locked under loads like going up a hill. Ive never really cared that it did it and usually it stopped if I ran 93, but this time I took out a lot of timing in the low rpm high grams per cyl. range. So now most of the table is going to be a couple degrees from stock. At low cyl. airmass levels wouldnt the stock tune have the optimal timing becuase there is less chance for knock?

I would think that but I dont know.
Im going to test it out tommarow.

[HINDZY]

im only a beginer here and dont know 2 much about tuining but there was a couple of things in your log i noticed that somebody might be able to shed some light on.

1. i thought that there seemed to be alot of timing in places

2. there seemed to be some huge dips in timing advance then sudden rise back up
as if it was knock but no knock has been logged, maybe burst knock?

3. there was knock retard logged in your stock log but none on your other log, was something done to fix this?

once again this may be nothing i just thought it was a little strange

[cmitchell17]

I agrees with you that there was a little to much timing I was using to much of my optimal timing.

I notice the huge drops in timing too, there always at part throttle, and I believe they are the reason for a jolt feeling right before its about to shift. Ive udated os to a 2002 os so mabey that fixed it.

Im pretty sure I left the Knock Retard Settings stock. But your right I never see any knock retard anymore, but its always been about like that. I can hear knock but can't see it.

[southern]

I am logging engine torque. Seems to peak around 3600-4000 range. I was looking at an log and saw 383 and was like wtf and then I noticed it was an auto VE log.

[cmitchell17]

Does the auto ve make the torque read high?

Mine peaks around 3600-4000too but only by about a couple ft. lbs. It remains in the 290+ range from 2000-4500 then starts to fall to 220ft.lbs. at 5600rpm.

[cmitchell17]

On one log after switching to a 2002os I noticed my Predidcted grams per cylnder climb to as high as .76. Before it would only go to as high as about .64. I logged again and they were lower back to about high 60's but they still looked higher than they were originally.

The troque looks like its the same mabey +5ft.lbs.

One thing that might explain it, I think I was using your ve table when the grams were at .76, but now im using a stock ve table from a 2002.

[southern]

so is the 02 os working better for you? aslo you found any timing tables or more info about them?

[cmitchell17]

The 2002os seems to make my shifts a little better. It would clunk on every downshift especially on the 3-2 and give a hard 2-3 at low tps. The 2002os seemed to help it a lot but it kind of seems its coming back, so I think ill just give up and deal with it shifting bad.

After copying and pasting all my idel stuff over it seems to be normal.

I havent found any spark tables from anybody but im still looking.


One thing ive been thinking about:
If people sell custom tunes for trucks that require 93octane for their best tune, then I would think that my timing should be just about whats in the optimal timing table becuase I have to run 93 to make the knock stop.
They have no benifit if you run 93 octane and they want the tune to make the most power, so I must be right in my thinking that the 27-30WOT timing is best.

Stock it goes up to about 27.

Ive found that with the optimal timing the low rpms high airmass needs to be dropped a lot. Like when the TC is locked (the gm settings keep it locked for a lot of the throttle) it starts to knock but stops after I drop the timing 3-5 degrees to about 1-3 degrees from stock.

Im also using the timing table from a 05+ truck when I blend it with the optimal timing.

Either way the optimal timing is only about 2-3/4 degrees off in the normal airmass ranges, but in the high airmasses its about 3-6/7degrees more.

But then you still have the question as to what condition gm got the table.
Mabey they got it at an AFR of 12.5 with a IAT of 50degrees with high octane fuel? But arnt there SAE standerds they have to follow, so what would the IAT's be then?

If they tested it with 93 then I guess we be just right running the full optimal timing. The LM7 only has like 9.5:1 compression so it seems you would be able to run optimal timing with a relativly low octane, but I don't know.

[southern]

I would think that they would tune for the worst conditions, since the tunes are all the same. That way it covers them and gives a safety net in there for when people pull loads with them. If they had them set up for best performance then it would be 93 octane and no heavy loads right?

[cmitchell17]

Will I guess the low octane spark table would be the best timing in the worst conditions.

The optimal timing would be the best timing in the best conditions.

But the IAT would be normal, best conditions: 72,80degrees
Sea level, Octane gas?, ECT?

Is 91/93 octane gas required to run the optimum timing with the diffrent truck heads? A LS1 optimal timing is lower than the vortec optimal timing(I think).

My knock sensor dosent think I need high octane it thinks 87s fine with whatever timing, but I hear knock with any kind of raised timing without 93 octane.

I might be overlooking something simple, but I don't see how a load on the motor would make it knock. Besides the fact that it might lower the rpms causing mabey more airmass in the cylinders.

I never see knock in the low end at wot. I always see it from around 3800-5200 and sometimes up.