MS3 and LT1 Camaro

Testing and development of Megasquirt 3

Moderators: jsmcortina, muythaibxr

Dookie454
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Re: MS3 and LT1 Camaro

Post by Dookie454 »

Thanks for the info shortbus. I will most likely go that route if I can at least get this thing running, now knowing the code for the Opti isnt actually finished that makes sense that nobody is using it, I thought it was simply needing enabled.

Well I got my MS3 reading RPM with the opti, though all the settings are different than everything documented (very bad MS3 documentation in my opinion as a new guy), for one tech support recommended following "how to megasquirt your chevy LT1 LT4 L99". and this didnt even come close to working, only could read up to 600rpm, then the second method I googled worked (http://www.msextra.com/doc/ms3/ignition.html#vrv357pull) after moving the 1K resister to pins R57 and adjusting the pots. But the software has to be set to "Rising Input" to get a smooth RPM signal, with it set to "Falling Edge" I would get a irregular RPM pattern even though the RPM was held constant. Weird I know. Not sure what effect all the other settings have but RPM is steady using my electric motor.

My concern now is, in Batch fire mode, how does the MS know what side to fire and when? Is it truly random each and every time I start it, and is that ok? I just want to get it running to I feel comfortable sinking even more money into crank and cam triggers.
MS3X on 2010 Camaro LS3 + Whipple @ 10psi + HPT + AEM 30-0333/0334 WB
MS3 Knock Module + JBPerf Dual VR v2.1 (Removed), didnt play well with LS3 DBW Motor, works for VSS.
OLD: 1997 Chevy Z71 Vortec 350, + BOSCH 0261231036 WB Knock Sensor
OLD: LT1 TA 700hp + MS3X
shortbus
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Re: MS3 and LT1 Camaro

Post by shortbus »

It is good you got to where you are now. Definitely follow the megasquirt manual.
I think the aim was to get the opti code to fire sequential. James will probably have to tell us.

I have an incomplete idea how batch mode works. But I don't think it matters which side fires fuel first.
Dookie454
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Re: MS3 and LT1 Camaro

Post by Dookie454 »

After thinking about it you are probably right, batch fire would not need timing per bank since the firing order alternates banks somewhat randomly. It would obviosly matter for sequential.

There is no real manual for MS3 on LT1, they say use MS2 instructions but they do not work. They are different enough to confuse someone like me. Megatune doesnt work for MS3 and thata what the instructions say to use.

I just hope the RPM is accurate and reliable towards 6500rpm, everything else I can figure out.
MS3X on 2010 Camaro LS3 + Whipple @ 10psi + HPT + AEM 30-0333/0334 WB
MS3 Knock Module + JBPerf Dual VR v2.1 (Removed), didnt play well with LS3 DBW Motor, works for VSS.
OLD: 1997 Chevy Z71 Vortec 350, + BOSCH 0261231036 WB Knock Sensor
OLD: LT1 TA 700hp + MS3X
jsmcortina
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Re: MS3 and LT1 Camaro

Post by jsmcortina »

In the MS3 manual you'll need to read the Fuel and Ignition sections and also for a 36-1 crank wheel, see here: http://www.msextra.com/doc/ms3/trigger- ... #misscrank

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
shortbus
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Re: MS3 and LT1 Camaro

Post by shortbus »

jsmcortina wrote:In the MS3 manual you'll need to read the Fuel and Ignition sections and also for a 36-1 crank wheel, see here: http://www.msextra.com/doc/ms3/trigger- ... #misscrank

James
Nice. That answered one of my questions.. my one tooth cam wheel is a "50/50 wheel".

Thanks.

I hope my race weekend goes well and that Monday comes soon so I can start installing my new parts.
Dookie454
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Posts: 344
Joined: Mon Jul 25, 2011 9:18 pm

Re: MS3 and LT1 Camaro

Post by Dookie454 »

that is good info. I have a question since it's about the opti settings I hope it's ok here?

I got the RPM reading very smooth spinning my opti with electric motor, all the way past 15,000rpm, however... there's a range from 3600-4400rpm that RPM continues to read fine BUT the MAP sensor locks up at whatever reading it was at when you enter that window (3600-4400) rpm. No vaccumm/boost will make it change, so this also means I dont see a change in injector pulsewidth or timing. RPM still moves though and no sync errors or anything else abnormal appears to happen.

Where should I even try to start? I changed a bunch of ignition settings and no change. I was so close to trying to start the car tonight with it too! :RTFM:
MS3X on 2010 Camaro LS3 + Whipple @ 10psi + HPT + AEM 30-0333/0334 WB
MS3 Knock Module + JBPerf Dual VR v2.1 (Removed), didnt play well with LS3 DBW Motor, works for VSS.
OLD: 1997 Chevy Z71 Vortec 350, + BOSCH 0261231036 WB Knock Sensor
OLD: LT1 TA 700hp + MS3X
Dookie454
Experienced MS/Extra'er
Posts: 344
Joined: Mon Jul 25, 2011 9:18 pm

Re: MS3 and LT1 Camaro

Post by Dookie454 »

Map Sampling? I has to be MAP Sampling.

MAP Sampling Function

Because of the various mechanical, sampling, and other minor inconsistencies that go along with a running engine, the MAP sensor is not only sampled one time at the specified angle. The angle specified in the MAP sample timing curve specifies the start of MAP sampling for a particular sampling event, at which time, the MAP sensor is sampled for the duration specified in the MAP Sample Window.

During the MAP Sample Window, the MAP sensor is sampled every 0.128 ms for the duration of the MAP Sample Window angle specified. Each sample is compared with the previous sample, and the lowest value between the two is stored temporarily. At the end of the sampling window, the value that was stored temporarily will contain the lowest value sampled during the whole window. This value is then used for all table lookups and calculations that involve MAP.
MS3X on 2010 Camaro LS3 + Whipple @ 10psi + HPT + AEM 30-0333/0334 WB
MS3 Knock Module + JBPerf Dual VR v2.1 (Removed), didnt play well with LS3 DBW Motor, works for VSS.
OLD: 1997 Chevy Z71 Vortec 350, + BOSCH 0261231036 WB Knock Sensor
OLD: LT1 TA 700hp + MS3X
Dookie454
Experienced MS/Extra'er
Posts: 344
Joined: Mon Jul 25, 2011 9:18 pm

Re: MS3 and LT1 Camaro

Post by Dookie454 »

So, I wired up the MS3 to the car piggyback on the stock PCM, controlling fuel only using an optis. It actually startup up first try! I was a little rich but now is around 14.7 at idle up to about 2000rpm. It's running batch fire bank to bank, 2 squirts per cycle, alternating, even fire.

It has a larger duration cam so idle is bumpy and hard to tell how even things are, but the thing is under light free revving, around 1500-2000rpm I feel a missfire like an injector is not squirting enough fuel (lean), if I put it in gear and load it just a little bit it runs smooth, just the free revving/free cruise is lean or missfiring like on one cylinder.

It doesnt do this with the stock PCM in sequential mode (all injectors shooting 100% injector offsets).

Im imagining the batch fire is causing a problem due to combination of cam/83lb injectors, but not really sure.

Is there something I could try changing in the fire pattern or injector setup that could help this?
MS3X on 2010 Camaro LS3 + Whipple @ 10psi + HPT + AEM 30-0333/0334 WB
MS3 Knock Module + JBPerf Dual VR v2.1 (Removed), didnt play well with LS3 DBW Motor, works for VSS.
OLD: 1997 Chevy Z71 Vortec 350, + BOSCH 0261231036 WB Knock Sensor
OLD: LT1 TA 700hp + MS3X
shortbus
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Posts: 175
Joined: Wed Jun 02, 2010 6:43 am

Re: MS3 and LT1 Camaro

Post by shortbus »

I am not a tuner expert yet. But I am pretty sure you have the tuning controls to fix all that. Have you tried to do the auto tune?
Dookie454
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Re: MS3 and LT1 Camaro

Post by Dookie454 »

well the auto tune will take care of the AFR VE settings but I manually adjusted the VE tables in the no load area this occured in to get it at about 14.5AFR. It's not a lean/rich problem, it's more like only one cylinder is missfiring under weak load (free spinning between 1400-2000rpm, haven't tried higher yet). This seems like only one cylinder is weak cause it shakes a bit, but very consistent as only one cylinder is doing it and it is not a random missfire like a lean or rich condition would create.

When I put a little load on it like engage 3rd gear (its a manual) the miss turns into mostly smooth power, but I havent driven it yet so I dont know how bad it will be in higher RPM's... but right now I know this range it will cause problems. I want to make sure this cyl is not lean under power as well and there's no good way to do that.

As far as the RPM signal goes, it's very consistent and smooth so I dont think it's a signal problem.

I was wondering if there is a problem with my injector settings or something else Im not aware of. Sure feels like a batch fire related problem to me.

I have cyl's 1,3,5,7 on bank 1, and 2,4,6,8 on bank 2, Im thinking about switching some wires around and see if it improves or gets worse, I was hoping someone had this problem but it doesnt appear to be the case.

I will probably post in the main forum, thanks!
MS3X on 2010 Camaro LS3 + Whipple @ 10psi + HPT + AEM 30-0333/0334 WB
MS3 Knock Module + JBPerf Dual VR v2.1 (Removed), didnt play well with LS3 DBW Motor, works for VSS.
OLD: 1997 Chevy Z71 Vortec 350, + BOSCH 0261231036 WB Knock Sensor
OLD: LT1 TA 700hp + MS3X
jsmcortina
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Re: MS3 and LT1 Camaro

Post by jsmcortina »

I think I have some good news for you... see http://www.msextra.com/forums/viewtopic ... 89#p292289

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
Dookie454
Experienced MS/Extra'er
Posts: 344
Joined: Mon Jul 25, 2011 9:18 pm

Re: MS3 and LT1 Camaro

Post by Dookie454 »

jsmcortina wrote:I think I have some good news for you... see http://www.msextra.com/forums/viewtopic ... 89#p292289

James
James, That is some of the best news I've ever heard! Now... How do I get a copy? :yeah!: My car is up and running and I'm ready to test!
MS3X on 2010 Camaro LS3 + Whipple @ 10psi + HPT + AEM 30-0333/0334 WB
MS3 Knock Module + JBPerf Dual VR v2.1 (Removed), didnt play well with LS3 DBW Motor, works for VSS.
OLD: 1997 Chevy Z71 Vortec 350, + BOSCH 0261231036 WB Knock Sensor
OLD: LT1 TA 700hp + MS3X
jsmcortina
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Posts: 39587
Joined: Mon May 03, 2004 1:34 am
Location: Birmingham, UK
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Re: MS3 and LT1 Camaro

Post by jsmcortina »

First you need to get yourself up to speed with the alpha13 code and I'll send you a development snapshot.

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
Dookie454
Experienced MS/Extra'er
Posts: 344
Joined: Mon Jul 25, 2011 9:18 pm

Re: MS3 and LT1 Camaro

Post by Dookie454 »

James, everything is setup on my bench unit except for the 330 ohm resistors, I only had 480 ohm and installed those. It reads RPM very good down low, but upwards of 5500rpm it starts losing sync, it might work for 5-10 seconds at 5500rpm then lose sync, then lower to 5000rpm and it comes back in. If I blast to 6000-6500 it might read for 1 sec but loses sync worse the higher you go.

Do you think the resistors cause this or do I need to adjust the pots?

It's ready very steady below these RPMS.
MS3X on 2010 Camaro LS3 + Whipple @ 10psi + HPT + AEM 30-0333/0334 WB
MS3 Knock Module + JBPerf Dual VR v2.1 (Removed), didnt play well with LS3 DBW Motor, works for VSS.
OLD: 1997 Chevy Z71 Vortec 350, + BOSCH 0261231036 WB Knock Sensor
OLD: LT1 TA 700hp + MS3X
jsmcortina
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Re: MS3 and LT1 Camaro

Post by jsmcortina »

I was able to test to 5600rpm without problem. In earlier testing I was using VRout instead of VRoutinv and got nasty sync-loss around 3000rpm and above. The value of the resistors might have some effect. If the rising edge of the low-res was becoming lazy at higher rpms due to the capacitor on the input, then the sync re-check can fail.

It is possible to re-write this if needed - the hi-res slots are used for timing and the low-res slots are used for cylinder and phase information and sync re-checking. The falling edge of the low-res signal is typically more stable so I could re-write the code to use that instead.

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
Dookie454
Experienced MS/Extra'er
Posts: 344
Joined: Mon Jul 25, 2011 9:18 pm

Re: MS3 and LT1 Camaro

Post by Dookie454 »

I adjusted the pots while running, adjusting the pot near the center a few turns clockwise I can get the high RPM to be very stable up to 14000rpm, but then it becomes unstable on the lower end, and will not "start" once stopped.

VRout instead of VRoutinv, how do you think mine is wired up? Im not sure.

I'll try to find some proper resistors and get back to you.
MS3X on 2010 Camaro LS3 + Whipple @ 10psi + HPT + AEM 30-0333/0334 WB
MS3 Knock Module + JBPerf Dual VR v2.1 (Removed), didnt play well with LS3 DBW Motor, works for VSS.
OLD: 1997 Chevy Z71 Vortec 350, + BOSCH 0261231036 WB Knock Sensor
OLD: LT1 TA 700hp + MS3X
jsmcortina
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Location: Birmingham, UK
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Re: MS3 and LT1 Camaro

Post by jsmcortina »

Dookie454 wrote:VRout instead of VRoutinv, how do you think mine is wired up? Im not sure.
The normal way of wiring uses VRout. With the two inputs as tested you need to change to use VRoutinv. This is covered in the manual page.

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
Dookie454
Experienced MS/Extra'er
Posts: 344
Joined: Mon Jul 25, 2011 9:18 pm

Re: MS3 and LT1 Camaro

Post by Dookie454 »

jsmcortina wrote: The normal way of wiring uses VRout. With the two inputs as tested you need to change to use VRoutinv. This is covered in the manual page.

James

This is what I did.. let me know what you think: http://www.msextra.com/doc/ms3/optispark.html using 480 ohm in place of 330 ohm (picking some 330 up today)

I did these specific steps: "On V3.57 see here and adjust per hall, but ensure on J1 is jumpered 5-6 only."
V3.57 board - VR Input
a) Find JP1 in the bottom right of the board. Place a jumper across positions 1 and 2
d) With a small screwdriver, turn the pots, R52 and R56, about 6 turns to the fully anticlockwise position (you may feel a "click") This sets them up for most VR sensors.
For hall, opto, points, TFI, EDIS, GMDIS, LS1 input turn R56 back about 2 turns clockwise.

Thanks James!
MS3X on 2010 Camaro LS3 + Whipple @ 10psi + HPT + AEM 30-0333/0334 WB
MS3 Knock Module + JBPerf Dual VR v2.1 (Removed), didnt play well with LS3 DBW Motor, works for VSS.
OLD: 1997 Chevy Z71 Vortec 350, + BOSCH 0261231036 WB Knock Sensor
OLD: LT1 TA 700hp + MS3X
jsmcortina
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Posts: 39587
Joined: Mon May 03, 2004 1:34 am
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Re: MS3 and LT1 Camaro

Post by jsmcortina »

That sounds ok. I'm testing with a V3.57 too.

However, I've tweaked the code to re-sync on the falling edge of the slot instead. I'll mail that over for you to test.

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
Dookie454
Experienced MS/Extra'er
Posts: 344
Joined: Mon Jul 25, 2011 9:18 pm

Re: MS3 and LT1 Camaro

Post by Dookie454 »

ok, I picked up 330 ohm resistors so I'll test both and let you know what differences I find. How long did you spin it at 5500rpm? For me it would often work if I revved it up then down but holding at 5500rpm would drop out within a few seconds, the higher I went the faster it would drop.

How long are your opti signal wires? Im using your Jimstim on the main board and the 12' long MS3X on the top, connected to the Jimstim for low res opti and 5v reference.
MS3X on 2010 Camaro LS3 + Whipple @ 10psi + HPT + AEM 30-0333/0334 WB
MS3 Knock Module + JBPerf Dual VR v2.1 (Removed), didnt play well with LS3 DBW Motor, works for VSS.
OLD: 1997 Chevy Z71 Vortec 350, + BOSCH 0261231036 WB Knock Sensor
OLD: LT1 TA 700hp + MS3X
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