are you using one of those voltage wot switches? if you are i bet the throttle actualy is closing and shuting off the nitrous, i could see mine close on atap and on the wideband, not even just at the shifts.

 

the throttlebody actually closes even when you have it floored with a fly by wire TB? maybe that's why the shifts are so soft in my mom's 03 yukon 5.3, it's basically stock also but the shifts are musshy.

 

No, I have it mounted to the plastic around the firewall, with the switch tripping by the petal. When I was installing it, it worked fine, but when I'm running and stomping on the petal, the WOT switch gets twisted by the petal and shuts off. At least thats what I thinks going on. Either that, or my soleniods aren't getting enough power or something. Not completely sure so I may have more than one issue. I do know that my nitrous is not on all the time like my old manual TB truck. I'm thinking of swapping to the NX voltage sensor switch this week.

I have it shifting at 6250, but I logged a 6615 value on a 1-2 shift, so my trans appears to be slipping some. So Jim, hurry up with that 80E swap.

 

hey big tex, did you catch the part of my swap where the output shaft is larger on the 4l80e? the 2 output shafts on the transfer case are the same for the 1500autotrack and the 2500hd transfercase so my driveshafts will work but i have to use the 2500hd transfercase. no more auto 4wd for me.

in your case you wouldn't be able to keep your AWD transfer case, have to change to something for a 2500, the autotrack for 2500 might work but i called a couple of places just to see how much and they didn't evel list them, just the electric shift and non electric shift ones. i am going to try the manual shift hd case and just leave it in 4hi, then let the front diferentil be the only disconect.

i ecpect to have all my parts by tuesday and have it running next weekend.

 

I heard somewhere that GM is going to add the 4L80E to the SS for next year. I dunno if that's BS or not.

How far do you want to take your truck power wise? You will lose the AWD if you go to a 4L80E too and pretty much defeat the purpose of it in the first place. The '03+ 4L80E's in the 2500HD truck you can get an AutoTrac transfercase so you may be able to convert to a part-time 4WD setup then.

I'd say a properly and fully built 4L60E should hold up to about 550rwhp in a heavy truck. Could be more.

 

Hey Parish.I have been gone for over a week and missed the bigger output shaft on the 4L80E.That is what i said 2 weeks ago and someone said i was wrong.Sounds like you have all the parts you need either way.Now what is your time frame again?

 

i hope to have it running by friday, i get the shorter/longer driveshafts back tomorrow, the stall and computer on tuesday and have the rest of what i need right here. here is some info

https://ls1tech.com/forums/showthread.php?t=112777
https://ls1tech.com/forums/showthread.php?t=113736

 

Ok Parish,you always have been a man of your word, when you say you are going to do something you do.Hope it all goes together like you plan,thanks for being the pioneer.How much time do you expect this to cost you based on your best ET yet with this truck?You will have a stall now were you didnt before right? Ok .3 tenths sound about right?
https://ls1tech.com/forums/showthread.php?t=108872

 

Hey parish.I will ask you first,you know my truck you can see my mods. Recenty my towing mileage and towing power took a dump.8MPG pulling around 5500LBs now. When i was getting since the time of the install 13.5 towing 4k LBS.-5Klbs.The power feels like the 5.3 when towing. The truck feels the same and has all the power it always had running empty.I did plug in my auto xray when towing and the SOB goes onto open loop at 58% throttle position,that was the only thing i could see on the scanner that was happening out of what i think is the norm.Ed wright shut off a lot of **** so it may want to code but there is none.Now that i am home i took off my UPD and the TBI spacer and swapped the MAP re-torqued the intake and installed my other ED wright that was getting me 33.5 degrees at WOT,other than that that PCM works great.Feel free to ask questions Thanks.BigTeX jump in anytime or others.Someone on here had a 6.0 fuel mileage take a dump,who was that? He did say new plugs made no difference,me neither.

 

sorry tex, not sure how this got to be about my truck

i dont expect it to cost me anything. before i ran a 13.48 with a 4.8, 100shot, electric fans, tstat. this round of mods adds...

6.0
py3400e
4l80e(slow me down some)
step up to a 150shot(for starters)
tuning with edit and wideband, delete TM, shift points.
upd intake

seems hard to imiagne not geting a second out of that. cutouts, fuel system and a larger shot are next in line if all goes well.