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WopOnTour
April 17th, 2005, 03:46 PM
Very impressed with EFI Live capabilities
I'm more of an OBDI hardware guy and have most of the tools but this is s&*t is so sweet!... props to the Devs

So anyways a Q:
On the OBDI boxes there is a cylinder select byte to allow the ECM to function in either 4,6 or 8 cylinder mode- is there anyway to change this on the LS1 PCM? OR Has anyone here successfully used the 8cyl calibration to operate a serious 4cyl (doing a boosted ECOTEC project and looking at options)

Any all comments appreciated (other than diss'n on the prospets of my ECOTEC project :oops: )
Regards
WopOnTour

Blacky
April 17th, 2005, 04:12 PM
I have no idea how or even if it can be done on the LS1.
But I think GM are coming out with a PCM controlled 4 cylinder mode for the LS2.

Regards
Paul

wait4me
April 17th, 2005, 04:36 PM
4.3 L is a 6 cyl in a v8 computer. i sent one to ross.. :) I think this could be done???

wait4me
April 17th, 2005, 04:42 PM
say for example, 1221256 operating system, at location 8027 , It will say what the cyl amount is. it is in 8 bit signed byte. a v6 cal will show 06 the v8 of the same operating system shows 08 :)

WopOnTour
April 17th, 2005, 05:10 PM
I have no idea how or even if it can be done on the LS1.
But I think GM are coming out with a PCM controlled 4 cylinder mode for the LS2.

Regards
Paul
Well on that note, the 2005 Supercharged Ecotec (ION Redline and Cobalt SS) uses an p12 PCM very similar the E40 shown in this thread
http://efilive.com/forum/viewtopic.php?t=567

How much of the calibration file of this box is known so far and what can EFILive do with this box on the LS2?? Does it maybe have a cylinder select capability?
Willing to donate a P12 with exisiting boosted ecotec software if anyone on the DEV team wants to take a look under the hood and see what they can do. Certainly with the P12 the possibility of an expanded market for your fine package might be added incentive?
Regards
WOT

wait4me
April 17th, 2005, 05:24 PM
can someone send me an unmodified bin? Ill play around with it too :)

WopOnTour
April 17th, 2005, 05:25 PM
say for example, 1221256 operating system, at location 8027 , It will say what the cyl amount is. it is in 8 bit signed byte. a v6 cal will show 06 the v8 of the same operating system shows 08 :)
Ahh right the 6cyl truck.
Sounds like a similar byte to the OBDI ECMs such as the 1227727/'730

0x8009 C0h ; cylinders mask (4=0x80, 6=0xC0, 8=0x00)
Well I guess the problem is I dont know if the LS1 box (1221256?) was ever used on a 4 cyl so maybe there will be no BIN to work from? Maybe better to go after a P12 solution?
Regards
WopOnTour

wait4me
April 17th, 2005, 05:30 PM
the pcm i was refering to was a 12200411 The operating system was the 1221256. The 4 cyl used a different computer.... From what i have seen anyways, ??

WopOnTour
April 17th, 2005, 05:46 PM
OIC Gotcha
Well I do have a calibration PN# for the latest oem reflash file (12594936) for the P12 in a 2004 Redline, but dont know how to offload it from the ECM so was attempting to "pinch it" off the TIS installation or CDs somehow. Any other way to do it?
Thanks
WOT

Blacky
April 17th, 2005, 06:09 PM
I have no idea how or even if it can be done on the LS1.
But I think GM are coming out with a PCM controlled 4 cylinder mode for the LS2.

Regards
Paul

Oh, I thought you were asking if the V8 operating systems can be modified to run an LS1 using only 4 cylinders :oops:

Yes, the LS1 PCM can run a 4 cylinder, but since there are no operating systems around for a 4 cylinder (that I know of) then it's going to be tough to figure it out. Probably too tough, since I believe some code in the PCM operating system is different between 6 and 8 cylinder applications (therefor one would assume different code for 4 cylinder operation as well).
What that means is you probably can't just recalibrate an existing OS for 4 cylinder operation. You'll probably need to make code (i.e. operating system) changes as well.

Paul

SinisterSS
April 17th, 2005, 10:23 PM
FYI - gearheads aren't supposed to ever deal with an engine less than 8 cylinders. 8)

GMPX
April 18th, 2005, 01:42 AM
Guys,

Are you sure the ECOTEC uses the E40?.
Some notes posted (edited) from a web site -

"GMPT Model Year 2004 Warren (E40) program Model Year 2004 V8 Engine Controller".

"GMPT MY2006 E38 Engine Controller Program, It is targeted for a variety of applications for passenger cars and trucks. It will work with 4, 5, 6, and 8 cylinder engine applications".

Looks like the E38 will be the universal controller, yes the E40 will run in 4cyl mode but perhaps only when in DOD mode.

As for the LS1 PCM, I suspect the problem would be the crank/cam trigger signals not being a match. If it were so universal GM would have the same PCM for the 4cyl engines and the 3800V6, of course they do not.

Cheers,
Ross

GMPX
April 18th, 2005, 01:44 AM
FYI - gearheads aren't supposed to ever deal with an engine less than 8 cylinders. 8)

Rick, you just know this thread will now turn into an argument now :wink:

Cheers,
Ross

SS2win
April 18th, 2005, 02:21 AM
Oh, I thought you were asking if the V8 operating systems can be modified to run an LS1 using only 4 cylinders :oops:


That could be useful if you're looking to make a big air compressor. :lol:

WopOnTour
April 18th, 2005, 02:39 AM
Sorry it is NOT an E40, but a P12 used AFAIK only on the supercharged ECOTECs

So I know THEY can be used in speed density or MAF, but figured it might take a couple years to sort out the code for remapping, rev/speed limiters, DTC masking etc etc, so was looking if the PCM used with the LS1 could been used in a 4cyl manner, or not.

Not too concerned at this point about the potential ignition issues as we can create pretty much any crank wheel required (4X for HVS based (2000 LD truck or even the asymetrical 24X for COP etc)

At this point just attempting to determine if it's viable of if we should be just focussing on reprogramming the P12 or aftermarket standalone such as the MOTEC.
Thanks
WOT

SinisterSS
April 18th, 2005, 03:29 AM
FYI - gearheads aren't supposed to ever deal with an engine less than 8 cylinders. 8)

Rick, you just know this thread will now turn into an argument now :wink:

Cheers,
Ross

People need to start putting a foot down to the younger generation. Imagine what sissy cars the ricers of today will be driving in 30 years. :o

It's called better gearheads through education. 8)

joecar
April 18th, 2005, 07:19 AM
FYI - gearheads aren't supposed to ever deal with an engine less than 8 cylinders. 8)
...and must have lots of cubes... 8) :D

WopOnTour
April 18th, 2005, 08:27 AM
Well I guess it could be a P5 not an E40
Anyone know how to tell the difference?
WOT

GMPX
April 18th, 2005, 09:55 AM
Well I guess it could be a P5 not an E40
Anyone know how to tell the difference?
WOT

It will either be stamped in the case or on a label.

Cheers,
Ross

emarkay
April 19th, 2005, 01:11 AM
FYI - gearheads aren't supposed to ever deal with an engine less than 8 cylinders. 8)

Rick, you just know this thread will now turn into an argument now :wink:

Cheers,
Ross

I thought it was more like "real gearheads don't let friends do FWD..."

:)

MRK

joecar
May 27th, 2005, 07:01 PM
I read that Crane Cams and Comp Cams can custom grind you a small block chevy cam with alternate firing order (so all you have to do is change the order of the spark plug wires on the distibutor); the reason you may want this "marine" firing order is that some people say it has better "intake balance and/or exhaust header balance (...something about 2 adjacent cylinders firing in sequence messes up tuned header design)", and "promotes better cooling".

So... thinking out loud, I'm wondering if it's possible to change the firing order in the LS1/LS6 PCM and get a alternate firing order cam ground...?
:?:

You could casually drop "...oh yeaarh, I changed my firing order..." in your converstions... he he he.

GMPX
May 27th, 2005, 09:35 PM
You could casually drop "...oh yeaarh, I changed my firing order..." in your converstions... he he he.

Yeah, just swap the wires!!, (I'm not kidding here!!).
As far as the PCM is concerned, it is just firing outputs A - H, how they are hooked onto the engine is upto the engineers.

Imagine running an old 455 Pontiac on an LS1 PCM :D

Cheers,
Ross

Delco
May 27th, 2005, 10:35 PM
You could casually drop "...oh yeaarh, I changed my firing order..." in your converstions... he he he.

Yeah, just swap the wires!!, (I'm not kidding here!!).
As far as the PCM is concerned, it is just firing outputs A - H, how they are hooked onto the engine is upto the engineers.

Imagine running an old 455 Pontiac on an LS1 PCM :D

Cheers,
Ross

Yah got me thinking Ross , We converted the shop 68 Firebird to Delco injection and stroked it to from a 400 to a 462 a few years back , may be time to upgrade the PCM and chuck a 4l80e into it - nah darn site easier to chuck a spare LS1 and a blower onto it than to do the conversion. :D

jsttry
May 28th, 2005, 03:18 AM
Spare LS1 and blower Delco? What are you running in the Monaro now then? ;)

And if the blower is spare send it up my way. I have a pesky silver clubbie to beat which means I need to drop from 13.0 to 12.7 somehow.

Delco
May 28th, 2005, 11:54 AM
Spare LS1 and blower Delco? What are you running in the Monaro now then? ;)

And if the blower is spare send it up my way. I have a pesky silver clubbie to beat which means I need to drop from 13.0 to 12.7 somehow.

I have a few spare LS1's laying around , no blowers though at present I sold my 2.4l whipple and are still awaiting the 3.3l whipple to turn up.

Monaro at present is running a the same bottom end as always - a 383ci 224 cammed daily driver :D The 3.3l should liven it up a little :D

joecar
May 30th, 2005, 01:58 AM
You could casually drop "...oh yeaarh, I changed my firing order..." in your converstions... he he he.
Yeah, just swap the wires!!, (I'm not kidding here!!).
As far as the PCM is concerned, it is just firing outputs A - H, how they are hooked onto the engine is upto the engineers.

Imagine running an old 455 Pontiac on an LS1 PCM :D

Cheers,
Ross

Ross, mate, you're pure genius... :D

joecar
May 31st, 2005, 11:02 AM
You could casually drop "...oh yeaarh, I changed my firing order..." in your converstions... he he he.

Yeah, just swap the wires!!, (I'm not kidding here!!).
As far as the PCM is concerned, it is just firing outputs A - H, how they are hooked onto the engine is upto the engineers.

Imagine running an old 455 Pontiac on an LS1 PCM :D

Cheers,
Ross

And you'd have to swap the injector wires also too, eh.

455 = big cubes -> big torque

455 + PCM = bigger and wider torque

(I wonder how big torque will be below 2000 RPM...? :) :) :) )