Torque Management: Pics of how it works

[Nick]

Originally Posted by 91_bowtie

I've never heard of a 5.3 getting 17/22. My friend's that have them here are seeing closer to 14/17.

The worst tank I've gotten has been 17, that was just driving in town. My '94 couldn't ge close to the mileage I get on the '04 and I have 95 hp more.




BTW, on you having friends.

[4x4K1500]

so my 96 doesn't have torque management? Or if it does would an SPE Proflash programmer get rid of it?

[91_bowtie]

Originally Posted by Nick99Chevy

The worst tank I've gotten has been 17, that was just driving in town. My '94 couldn't ge close to the mileage I get on the '04 and I have 95 hp more.




BTW, on you having friends.

I know that the MPFI is more efficient than TBI. I'm just saying that the mileage is not very significant. I've gone through 3 full thanks on the tahoe, and I've been averaging 14.5mpg. Thanks to the engineers at GM, I'm not seeing close to the advertised HP rating. My TBI, which got 13mpg in the city, is MUCH quicker than the tahoe.

[Hit Man X]

Originally Posted by 91_bowtie

I've never heard of a 5.3 getting 17/22. My friend's that have them here are seeing closer to 14/17.

My Z averages 15.5mpg and gets nearly 20mpg on the freeway...that's in an ECSB LT package with a big stereo and nearly 6000lbs. 285 ATs, 3.73:1 gears, and few bolt on mods. I have a full custom tune also from Allen Nelson.

I cruise 65-72mph only on the freeway. You must remember you're driving a heavy truck not a light aerodynamic car.

[justin]

Originally Posted by 91_bowtie

I know that the MPFI is more efficient than TBI. I'm just saying that the mileage is not very significant. I've gone through 3 full thanks on the tahoe, and I've been averaging 14.5mpg. Thanks to the engineers at GM, I'm not seeing close to the advertised HP rating. My TBI, which got 13mpg in the city, is MUCH quicker than the tahoe.

Jenna's Tahoe gets right around 14.5 average as well. I figured it would do better than my truck, since the sticker claims were higher... but nope.

How does it do on the highway? I was able to get 19mpg one trip with the SS, so a 5.3 should be able to get 20-21 on that same trip, assuming similar driving manners...

[Dan R.]

Thanks for the interesting information. I have to say, as ignorant of current ignition curves as I may be, that your complaint of the timing being dumped when you open the throttle sounds like the same thing you see with a timing light on an older vehicle- the vacuum advance does the same thing in response to load changes. Also, aren't they just momentarily backing off ignition advance during a shift to soften it up? Thanks again.

[91_bowtie]

Originally Posted by justin

Jenna's Tahoe gets right around 14.5 average as well. I figured it would do better than my truck, since the sticker claims were higher... but nope.

How does it do on the highway? I was able to get 19mpg one trip with the SS, so a 5.3 should be able to get 20-21 on that same trip, assuming similar driving manners...

I was also a little dissapointed with the 14.5mpg. I knew it would be around 15, and it wasn't really a concern of mine. I hope to have a Nelson tune by the end of November.

Last weekend, I picked up an exhaust tip from a 2004 SS. I just hope the Magnaflow I got isn't too loud.

[justin]

Originally Posted by Dan R.

Thanks for the interesting information. I have to say, as ignorant of current ignition curves as I may be, that your complaint of the timing being dumped when you open the throttle sounds like the same thing you see with a timing light on an older vehicle- the vacuum advance does the same thing in response to load changes. Also, aren't they just momentarily backing off ignition advance during a shift to soften it up? Thanks again.

That would be understandable. But in my situation, even moderately going from closed throttle to WOT, you can very noticably feel the acceleration fall off as you get above 1/2 throttle. WOT downshifts into high rpms feels like there is no power at all

[Nick]

Originally Posted by justin

That would be understandable. But in my situation, even moderately going from closed throttle to WOT, you can very noticably feel the acceleration fall off as you get above 1/2 throttle. WOT downshifts into high rpms feels like there is no power at all

Get a tuned PCM, I put a pcmforless in my '04. Pull's much harder than it used to.

[justin]

Originally Posted by Nick99Chevy

Get a tuned PCM, I put a pcmforless in my '04. Pull's much harder than it used to.

Yeah, I intend to... or take the class offered on EFI101.com... and purchase HPTuners software and do it myself...

How much did your pcmforless cost ya?

[Nick]

Originally Posted by justin

Yeah, I intend to... or take the class offered on EFI101.com... and purchase HPTuners software and do it myself...

How much did your pcmforless cost ya?

$250, Feels much better. Firmer shifts, speed limiter gone, gets mean on the kickdowns now. Have about 200 miles on it since the tune, I'm starting to notice a HP gain now.

Bryan Herter, the tuner for them, said he gained 32 hp at the wheels on his 04 SS.

[oldred95]

I know there is a night and day difference between a TBI and a vortech but can a programmer tune the computer on a TBI engine so it doesn't retard the timing? I have checked my truck at an idle and the stupid computer keeps the timing somewhere around 25 degrees BTDC. Would there be any downsides to this, or would it have terrible pinging and spark knock?

[Troll]

25 degrees BTDC means that the timing is advanced. To check the base timing on a TBI you need to disconnect the tan wire that is near the junction box on the firewall. I don't believe TBI 's have torque managment, at least not like the NBS has. Your TBI would benefit from a performance chip, but you might need to run a higher octane gas to prevent pinging.

[oldred95]

The always get the advance and retard mixed up. I have checked the timing with the wire unhooked and everything but I checked just to see what was going on when it was hooked up and the timing was way advanced. So when a chip burner says they change the ignition curves does that mean they monkey with the timing so it doesn't advance it and keeps it at the base timing?

[Troll]

I believe the base timing is 2 deg BTDC. Yes, changing the ignition curve would be messing around with the timing. You want it to be advanced to get more power. However, too much advance will cause detonation. That is why you have to run super unleaded with a performance chip or tune to prevent this.

[oldred95]

So I need to set if after top dead center or before to make the most power?

[Troll]

You want to set it before top dead center, which will be advanced. This will make the plug fire before the piston gets to the top of the cylinder. When I had my 89, I had my base timing at 4deg. BTDC. I would advance the base timing about 1 degree untill the engine would ping under a load with the AC on. Then back the timing off untill it doesn't ping any more. You will have to make several runs to do this. I tested mine by going up an overpass at wot. If you have a scanner you can check for knock retard. That will show you if the ECM is picking up any detonation. If not, just listen for the pinging.
A dyno would be the best way to do this, but not everyone has a dyno in their garage.

[SSMANIAC]

PCMFORLESS took care of the POS Torque management in my truck, love the difference now. nice to see the numbers thanks

[justin]

Originally Posted by Nick99Chevy

$250, Feels much better. Firmer shifts, speed limiter gone, gets mean on the kickdowns now. Have about 200 miles on it since the tune, I'm starting to notice a HP gain now.

Bryan Herter, the tuner for them, said he gained 32 hp at the wheels on his 04 SS.

Gracias. I will probably have to pick one up for Jennabear and one for me then in the next month or two

[Reds]

With the PCMFORLESS do you have to run high octane gas?