beertestr

iTrader: (5)

What ambient temps are you finding the loss of power? Is it really hot out, or is it wintry?

If it is not too warm where you are, then welcome to the great white North!!

IF it is soft, I still think it is the 4.10's not allowing the 2-1 downshift. If you wanted more, have a programmer move the max speed detent points up, but realize that the short 2-1 downshift WAAAAAAA will get shorter UNLESS you pull the 1-2 WOT shift point up. Every truck I have seen upshifts at about 5600 1-2 and 5200 2-3 and 3-4. You can push that up, but there is no way to make it do that only when you want it, your WOT upshift speed will always be what they change it to. I am not sure if you would see much acceleration benefit for spinning the engine so high, just more time 1st when you get the downshift.. If you know anybody with a similar truck, but 3.42's or 3.73's, you may want to try their truck and see if you like it better, I think the 4.10's are a bit much unless you are towing at GVW often. You give up 2-1 downshift availability, and more importantly to me, you lose 4-2 downshift availability on the highway.


If it is sunny and hot where you are (80+F), you suck..

The L33 got a bump in compression, so it is more prone to knock. The cals usually pull spark when sensors are reading levels that make the engine more prone to knock. Specifically, coolant temp and inlet air temp are big contributors to telling the PCM to pull spark. If your coolant temp is reaking a bit high, there is a good chance you are pullingspark. If the inlet temp is high, same thing. Both of these sensors are good indicators of the engine's propensity to knock, along with TPS and MAP. If you are losing power on warm days, a 160 t-stat might add a little room to keeping the coolant temps lower, and reducing the spark retard.

Mike_J

Temps have been on the cooler side since I've had the truck. I'm in WV so the extremes go from below 0 to around 100 degrees.

I wanted 3.73 gears, but in the half ton 4x4 for '05 its either 3.42 or 4.10. Given the mountains around here the low gears seemed like a no-brainer.

My friend and I have decided to get one of the programmers that use a laptop to hook to the truck. He is much more knowledgeable about the programmer since he has an '02 like my '05 and has been reading up on the 5.3L for awhile now.

I think that will be my start point for this project.

zippy

programming it yourself is probably a great place to start. not many have went after L33 tuning, post some updates as you go.

therock

iTrader: (2)

As posted above, I too have the L33. Another thing I have noticed better on the 05 than my previouse trucks is the 05 seems to shift much better. Much faster between gears and a tad firmer too. How about yours?
We will be all ears on the tuning. Good Luck.

tooquick2beslo

Does the L33 come in the avalanches too ?

04BlackGmc

iTrader: (18)

Just get the basics.. Tune CAI and exhaust...Stock computer is the DEVIL!

Mike_J

I'll definately post updates as I get them. Dont anticipate to do anything for at least another month or so though. Starting from scratch here. Previous expirence was with the good old 350's , carbs and TBIs.

Can't really comment on the tranny too much, my last truck was a '95 w/ 350 auto. I installed a Superior shift correction kit. I think when I had the kit installed that one shifted quicker and firmer (not as much power going through it though). When the tranny was rebuilt at 150K miles, it was done with stock GM parts and it seemed to shift softer, just like my friends all stock '98. The '05 shifts better than the '95 after the rebuild, only as mentioned before the '95 ALWAYS downshifted when you needed it too.

Wouldnt mind a slightly firmer shift. I've been told they have problems with the sun shell stripping out? Anything that can be done to prevent this...or did they make any changes for '05?

WvGearhead

So guys how hard is it to learn tuning with hp tuners? Mike_J and I might in on this purchase. I really like to learn how to do it myself instead of getting a mail order done. Hopefully it will help my 01 5.3 and mikes 05.

zippy

i believe the only other vehicle is the tahoe.

ludicrist2500hd

ecsb Z71 only as per gm

I have an 05 L33 3:42's , it is a little soft in the bottom end . I came from a 2500hd ecsb 6.0l 4:10s so i no what your saying . I just got the hp tuners and I'm waiting for a software fix from them to use it . I think the torque managment takes away some low end I'll post a review when it works .