lly doesn't have the bottom end

duratothemax

<--- slippery roads
Aug 28, 2006
7,139
10
0
Wyoming
Its mostly the charger IMO. Ive driven my truck back to back with a stock LLY turbo and a stock LBZ turbo. LBZ turbo is 10x more fun. Not to mention the LBZ turbo exhaust brake kicks the LLY turbos exhaust brakes ass.....

I love stock LBZ chargers....

Ben
 

Jakemax04

New member
Jun 28, 2013
127
0
0
I can't complain about no bottom end in my LLY. I'm biased as this has been the only model I've owned, but I don't have enough Turbo lag to complain about. I can definitely smoke the tires. At $200 a piece, I try and get the power to the ground tho:)
 

catman3126

Ehhh?.... You don't say?
Jul 24, 2012
2,636
0
36
NE Oregon
I believe it has everything to do with the combination of the slow non CAN electronics, the larger turbo, the pump not ramping up whether it has to do with the pump or the electronics controlling the pump but if you have ever scanned a LMM vs LLY you will see how much quicker the cp3 ramps the pressure up when you mat the throttle. And on diesels the lesser compression seems to be key in making them more responsive.
 

onebaddmaxxx

Active member
Feb 22, 2009
1,212
1
38
Cecil County Md
I believe it has everything to do with the combination of the slow non CAN electronics, the larger turbo, the pump not ramping up whether it has to do with the pump or the electronics controlling the pump but if you have ever scanned a LMM vs LLY you will see how much quicker the cp3 ramps the pressure up when you mat the throttle. And on diesels the lesser compression seems to be key in making them more responsive.


I think you'd find this statement backwards. Put 15.5:1 pistons in your truck and change nothing else. It will lag more
 

clrussell

pro-procrastinator
Sep 23, 2013
5,928
399
83
Its mostly the charger IMO. Ive driven my truck back to back with a stock LLY turbo and a stock LBZ turbo. LBZ turbo is 10x more fun. Not to mention the LBZ turbo exhaust brake kicks the LLY turbos exhaust brakes ass.....

I love stock LBZ chargers....

Ben

I've been reading this thread and wondered about this since I have an lbz charger sitting in the floor that's perfect...

Wonder how much difference it would make on an zf truck?
 

Lparrill

And here we go again
Jul 30, 2010
445
9
18
Lander, WY
My buddies LBZ lights alot faster than my LLY. I always planned on swapping to a LBZ turbo when I put a twin kit on my 05
 

duratothemax

<--- slippery roads
Aug 28, 2006
7,139
10
0
Wyoming
I believe it has everything to do with the combination of the slow non CAN electronics, the larger turbo, the pump not ramping up whether it has to do with the pump or the electronics controlling the pump but if you have ever scanned a LMM vs LLY you will see how much quicker the cp3 ramps the pressure up when you mat the throttle. And on diesels the lesser compression seems to be key in making them more responsive.

LB7/LLY ECM's do have CAN....................................

Its tuning and the turbo. I have a stock LBZ turbo on my LLY. It lights instantly, once I adjusted tuning for the LBZ charger. Much faster than a stock LLY turbo.

You cant compare logs. 2006+ ECM's log over GMLAN. 2005 and older ECM's log over Class 2/J1850. The frame rate is much much faster on 2006+ trucks. That doesnt mean the ECM is running that much slower, its just that you cant read live data as fast.....

And no, its more compression that makes them more responsive. Ive run lots of chargers and several different compression ratios. Stock LB7/LLY (the highest) is more snappy than any of the others. Tuning and turbos can account for the lower compression, but if you do nothing but change CR, the lower CR will be lazier feeling.
 

catman3126

Ehhh?.... You don't say?
Jul 24, 2012
2,636
0
36
NE Oregon
I think you'd find this statement backwards. Put 15.5:1 pistons in your truck and change nothing else. It will lag more

To each there own. ever seen Mark from Danvilles duramax videos with 15.5:1 pistons in it? that thing has more throttle response then any duramax I've ever seen. but I don't know everything.
 
Last edited:

catman3126

Ehhh?.... You don't say?
Jul 24, 2012
2,636
0
36
NE Oregon
LB7/LLY ECM's do have CAN....................................

Its tuning and the turbo. I have a stock LBZ turbo on my LLY. It lights instantly, once I adjusted tuning for the LBZ charger. Much faster than a stock LLY turbo.

You cant compare logs. 2006+ ECM's log over GMLAN. 2005 and older ECM's log over Class 2/J1850. The frame rate is much much faster on 2006+ trucks. That doesnt mean the ECM is running that much slower, its just that you cant read live data as fast.....

Yeah I didn't mean compare logs that way. So if the data can't read as fast is the ecm processing it as fast?

And no, its more compression that makes them more responsive. Ive run lots of chargers and several different compression ratios. Stock LB7/LLY (the highest) is more snappy than any of the others. Tuning and turbos can account for the lower compression, but if you do nothing but change CR, the lower CR will be lazier feeling.

So then why does anyone lower the comp ratio?
 

catman3126

Ehhh?.... You don't say?
Jul 24, 2012
2,636
0
36
NE Oregon
So if it has to do with the turbo solely then why when I changed the TLIQ (torque limited injection quanity) table did it have instant response like the LBZ/LMM, the changes I made, made mine shift terribly hard but the throttle resonse was instant. I could roll down the road and stab the throttle and blow the tires off at 15-20 mph. the way mone is now I stab it and it's 1.5 secs smoke, smoke, spool and then it will light the tires somewhat. I would have kept trying to dial int he TLIQ and see if I could get it to shift smoke but i didn't want to replace an input shaft during the leanring pricess just to gain throttle respone lol. yeah that harsh of shifts.