LS3-480 ECU questions
07-08-2012, 09:47 PM
#1
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Thread Starter
LS3-480 ECU questions
I've dug through the LS swap sticky--and wondered if someone could break it into smaller chunks somehow. I'm not sure of the tech, but seems like once a library gets too big, you need a system to find your way around!
I'm doing an LS3 swap into my low mile 78. I've done a lot of research, but the ECU tuning and programming eludes me. I went to the tuners forum and got more confused, so came back to the gearheads where I'm at home. Can someone help me with these ECU questions--
1. I've read that the 480 hp programmed ECU does not have all of the combustion tables that are in the standard LS3 ECU-- and worse, that the controller cannot be wiped entirely to remedy this lack, i.e. even after retuned, the controller always has this weak library that is missing tables. Anyone heard of or know what I'm talking about? Seems it would have to be bogus, but I've gotta know!
2. The GMPP accessory systems all come with variable displacement AC compressor, but the controller specifies that it doesn't control the AC. That doesn't make sense, but I've seen no complaints--so does it? Or does everyone end up dropping a Sanden in there, and run it with their C3 system--perhaps looking for the compressor power at WOT during the tune to drop power? Anyone used the standard gm variable displacement AC compressor with a stand-alone GMPP ECM?
3. I've read a bunch about the Mast M90, and even looked closely at their HO Cam/Springs/m90 controller packages (why don't they put prices up there!
). They seem to be highly prized. Question--is the M90 better than the GMPP controller, or once you start tuning-- they end up with similar abilities? Any tuner types that can help me understand the differences here?
4. I've read that the quality of the fuse box and entire ECM is lower quality of fabrication then expected from GMPP. Some argue that a pull-out rewire of a late model harness is much superior to this packaged controller. Anyone describe their experience?
And this last bonus question is an opinion question about value. GMPP offers the LS3 as a "connect-and-cruise" package with tranny, controllers, sensors--all but front accessories and starter. The 480 hp package comes with a 4L70e tranny, and the 430hp unit with the 4L65 tranny. Net price difference=$800. Is 50 hp, and one size up tranny worth $800--or is the tranny irrelevant and a bump stick and spring package from Comp Cams would be a wiser spend?
I haven't posted a thread before-- so besides writing to much, let me know where I screwed up?!
Les
I'm doing an LS3 swap into my low mile 78. I've done a lot of research, but the ECU tuning and programming eludes me. I went to the tuners forum and got more confused, so came back to the gearheads where I'm at home. Can someone help me with these ECU questions--
1. I've read that the 480 hp programmed ECU does not have all of the combustion tables that are in the standard LS3 ECU-- and worse, that the controller cannot be wiped entirely to remedy this lack, i.e. even after retuned, the controller always has this weak library that is missing tables. Anyone heard of or know what I'm talking about? Seems it would have to be bogus, but I've gotta know!
2. The GMPP accessory systems all come with variable displacement AC compressor, but the controller specifies that it doesn't control the AC. That doesn't make sense, but I've seen no complaints--so does it? Or does everyone end up dropping a Sanden in there, and run it with their C3 system--perhaps looking for the compressor power at WOT during the tune to drop power? Anyone used the standard gm variable displacement AC compressor with a stand-alone GMPP ECM?
3. I've read a bunch about the Mast M90, and even looked closely at their HO Cam/Springs/m90 controller packages (why don't they put prices up there!
). They seem to be highly prized. Question--is the M90 better than the GMPP controller, or once you start tuning-- they end up with similar abilities? Any tuner types that can help me understand the differences here?4. I've read that the quality of the fuse box and entire ECM is lower quality of fabrication then expected from GMPP. Some argue that a pull-out rewire of a late model harness is much superior to this packaged controller. Anyone describe their experience?
And this last bonus question is an opinion question about value. GMPP offers the LS3 as a "connect-and-cruise" package with tranny, controllers, sensors--all but front accessories and starter. The 480 hp package comes with a 4L70e tranny, and the 430hp unit with the 4L65 tranny. Net price difference=$800. Is 50 hp, and one size up tranny worth $800--or is the tranny irrelevant and a bump stick and spring package from Comp Cams would be a wiser spend?
I haven't posted a thread before-- so besides writing to much, let me know where I screwed up?!
Les
07-09-2012, 03:14 AM
#2
Drifting
Have you been over to ls1tech.com?You may find more answers over there,lots of experience there with all the various PCM's and tuning.The GMPP stuff seems a bit pricey,(no such thing as econo,cheap or budget when it comes to these swaps
)you may be better off sourcing your harness and PCM from other sources.I don't think I would trust 480hp to a bone stock 4L65 or 4L70e,they have enough trouble standing up to a 4.8 or 5.3 in a pick up truck,more torque and hp will only kill it faster,its not if you will be rebuilding or replacing it-but when. 
)you may be better off sourcing your harness and PCM from other sources.I don't think I would trust 480hp to a bone stock 4L65 or 4L70e,they have enough trouble standing up to a 4.8 or 5.3 in a pick up truck,more torque and hp will only kill it faster,its not if you will be rebuilding or replacing it-but when.
07-09-2012, 06:45 AM
#3
1. LS1tech.com has a PCM tuning forum. Lots of info there. Pro-touring.com has an LSx forum too. I've seen several posts about the GMPP LS3 packages there and in their buils forums.
2. There variable displacement compressors will work with an older AC system or one designed for fixed displacement. Howerver efficiency is decreased. You need to integrate the pressure sensor in the system in order to get the ecu to control it. Even later fixed displacement units are controlled via data link from thr BCM. Guessing GM didn't want to make it too complex. You can useAC without ecu. I'm driving 2 swaps with Vintage and Classic Auto Air, no ecu control, no problems.
3. Mast stuff is very pricey. Not sure if their controller has any greater capabilities rgan GM stuff.
4. No experience there. I did completely rewire my car becausr of so many changes and integrated a harness I reworked myself.
The extra 50 hp is only ay 6000 rpm+, not worth much in my opinion, but it's supposed to have a more lumpy sound.
2. There variable displacement compressors will work with an older AC system or one designed for fixed displacement. Howerver efficiency is decreased. You need to integrate the pressure sensor in the system in order to get the ecu to control it. Even later fixed displacement units are controlled via data link from thr BCM. Guessing GM didn't want to make it too complex. You can useAC without ecu. I'm driving 2 swaps with Vintage and Classic Auto Air, no ecu control, no problems.
3. Mast stuff is very pricey. Not sure if their controller has any greater capabilities rgan GM stuff.
4. No experience there. I did completely rewire my car becausr of so many changes and integrated a harness I reworked myself.
The extra 50 hp is only ay 6000 rpm+, not worth much in my opinion, but it's supposed to have a more lumpy sound.
07-09-2012, 09:55 PM
#4
Drifting
Can't help to much in the tuning department, but I can say that if you need someone to help you with a base starter tune, I would recommend http://tunedbyfrost.com/ Steve Williams is great to work with and will be helping me with my tune via my HP tuner program software, I will be street tuning the car and having Steve help me tweak the program through Email down loads since I don't have a dyno tuner near by. I will in time learn the tuning aspect of the LS swaps and use what I learn from Steve on my next LS swap I will be doing in my truck.
Your LS3 tuning questions may also be better answered if posted at Hp tuners Forum in the tunning section
If you wanted to go after market with a control and harness, http://www.holley.com/550-602.asp and a few others that have slipped my mind at this moment offer after market controllers and harness.
The 4L70E is a junk transmission in it's stock forum, just ask most SS Trail Blazer owners that have added HP to their setups. The input and out put shafts are weak and will not tolerate much horse power or abuse over 400 HP, also the servos in the trans are prone to fail as well. I would stick with the 4L60E, 4l65E, or 4L80E, these seam to have very little problems from what I have read.
Riggs
Your LS3 tuning questions may also be better answered if posted at Hp tuners Forum in the tunning section
If you wanted to go after market with a control and harness, http://www.holley.com/550-602.asp and a few others that have slipped my mind at this moment offer after market controllers and harness.
The 4L70E is a junk transmission in it's stock forum, just ask most SS Trail Blazer owners that have added HP to their setups. The input and out put shafts are weak and will not tolerate much horse power or abuse over 400 HP, also the servos in the trans are prone to fail as well. I would stick with the 4L60E, 4l65E, or 4L80E, these seam to have very little problems from what I have read.
Riggs
07-17-2012, 12:53 PM
#5
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Thread Starter
Thanks for the feedback from each of you--believe it or not, I've been having trouble posting back to this! Some error about something out-of-date when I finish typing in all my information--it is very annoying as then I have to THINK it all again, then type again! So hopefully, doing this on my PC rather than my iPad or iPhone will make it work!
Based on your thoughts, and on some other research, it seems like sticking with the stock 430HP LS3 is where I should start. I can add the cam / springs / whatever that fits me better after I find out what the base does in my C3. Also have seen where the stock 4L70e does not get much love anywhere. The 4L65 has the 5 pinions, and seems to be the favorite of the Automatic systems. The stock system comes with LS3 & 4L65E, with controllers from GM for both engine and tranny.
I don't like the idea of losing any efficiency on a GM variable displacement compressor. You guys all know that the C3 isn't an icebox--and I haven't yet ripped out all the interior to isolate me from the heat. There is another member down here in Jacksonville FL, and he'd agree that we need all the AC we can get! Losing any bit of capability at the compressor seems like a bad idea. I think I will use a Sanden compressor, and lose the variable displacement. I wonder though--if I'm using a 'standard' 430hp LS3, what stops me from putting a standard 2009 LS3 (C6) software in, then clipping out the security and other things? Wouldn't this then allow control--or is this then a wiring complexity (I can handle a few wires, even a solenoid or two, but I'd not like to mess with any kind of analog output device to accommodate AC.) I guess that all gets into 'Tuning.'
I've got to say that though I love the way the LS systems run, there really is something to say about HEI and no computer chips to deal with... But, I'd like to drive this every day for at least 30 minutes each way--so I guess I need the mpg from the tune. Look under the hood of any 1940's car, and see the grass, or parking lot under there--the motor looks like an ice cube in a glass--the LS definitely fills the glass.
I'm just starting this swap, and I am already considering a truck swap too--my 1990 F150 still runs ok, but loses some oil...burns LOTS of gas, and I'm not convinced that there is such thing as a great Ford engine to drop into it. But try to find anyone on line interested in a F150 swap--Fox Body yes, truck--no one. Weird, but these guys all lose their minds when someone wants to mix a Chevy engine into a Ford body. I like the truck...a 5.3 would be a nice fit in there.
Thanks for all the information guys. I'm going to go with the standard LS3, non-GM air compressor, and stick with the GM ECU (for now.) I guess I'm also going to have to learn more about Tuning. (sigh.) Sorry so long in my reply.
Based on your thoughts, and on some other research, it seems like sticking with the stock 430HP LS3 is where I should start. I can add the cam / springs / whatever that fits me better after I find out what the base does in my C3. Also have seen where the stock 4L70e does not get much love anywhere. The 4L65 has the 5 pinions, and seems to be the favorite of the Automatic systems. The stock system comes with LS3 & 4L65E, with controllers from GM for both engine and tranny.
I don't like the idea of losing any efficiency on a GM variable displacement compressor. You guys all know that the C3 isn't an icebox--and I haven't yet ripped out all the interior to isolate me from the heat. There is another member down here in Jacksonville FL, and he'd agree that we need all the AC we can get! Losing any bit of capability at the compressor seems like a bad idea. I think I will use a Sanden compressor, and lose the variable displacement. I wonder though--if I'm using a 'standard' 430hp LS3, what stops me from putting a standard 2009 LS3 (C6) software in, then clipping out the security and other things? Wouldn't this then allow control--or is this then a wiring complexity (I can handle a few wires, even a solenoid or two, but I'd not like to mess with any kind of analog output device to accommodate AC.) I guess that all gets into 'Tuning.'
I've got to say that though I love the way the LS systems run, there really is something to say about HEI and no computer chips to deal with... But, I'd like to drive this every day for at least 30 minutes each way--so I guess I need the mpg from the tune. Look under the hood of any 1940's car, and see the grass, or parking lot under there--the motor looks like an ice cube in a glass--the LS definitely fills the glass.
I'm just starting this swap, and I am already considering a truck swap too--my 1990 F150 still runs ok, but loses some oil...burns LOTS of gas, and I'm not convinced that there is such thing as a great Ford engine to drop into it. But try to find anyone on line interested in a F150 swap--Fox Body yes, truck--no one. Weird, but these guys all lose their minds when someone wants to mix a Chevy engine into a Ford body. I like the truck...a 5.3 would be a nice fit in there.
Thanks for all the information guys. I'm going to go with the standard LS3, non-GM air compressor, and stick with the GM ECU (for now.) I guess I'm also going to have to learn more about Tuning. (sigh.) Sorry so long in my reply.
