V10 viper Odd TDC Injector timing?

[Exige]

Hello

 

what would be correct injection timing for Viper 8.3 

base ignition timing is set correctly (done with timing light)

60-2 crank trigger wheel + stock cam wheel

left side of the engine (cyl 2,4,6,8,10) runs leaner at free rev rpms like 2000-3000-4000 and exhaust manifold gets RED hot. 

AFR on left side cyl 2,4,6,8,10) goes lean 16-18  and right side is OK 13-14AFR (cyl 1,3,5,7,9)

i set custom dtc points to:

 0    72    144    216    288    360    432    504    576    648

Firing order is:

1    10    9    4    3    6    5    8    7    2

ignition is set to: Odd fire wasted spark
injectors are set to: Multipoint-Group

Injector outputs active : 1-6

Injection Rate: 1

Injector Timing is set to: End of injection / 340

can be this issue?

physically there is no fuel pressure issue, injectors tested on flow bench and all is perfect. i even have fuel pressure sensor on fuel rail and monitor it so it is not changing with rpm.

i dont understand how one side can go lean and other stay good. 

there is no close loop fuel control, it is OFF.
 

so left side on Idle is richer than right side, and on free rev higher than idle RPM left side gradually goes lean up to 20afr.
switched lambda sensors and still the same
even without lambda u can see blue flame coming out of exhaust on 2000-3000rpm when right side no flame at all
and left side pops continiously on idle.

checked ignition pairs:
IGN1 Cyl 1&6
IGN2 Cyl 10&5
IGN3 Cyl 9&8
IGN4 Cyl 4&7
IGN5 Cyl 3&2

injector pairs:

INJ1 Cyl 1&10
INJ2 Cyl 2&7
INJ3 Cyl 3&6
INJ4 Cyl 4&9
INJ5 Cyl 5&8

what else to look for?

please suggest

viper-base.pclr

[Adamw]

Your TDC angles are wrong which means your spark is ~20 retarded on every 2nd cyl.   The TDC angles you have set are evenly spaced 72 deg apart which would be an even fire engine - you would need a block with a 72deg vee for this to work.  

The viper block is a 90deg vee, so when coupled with the shared crank pins that are 72deg evenly spaced you end up with odd firing angles 54 & 90deg apart.  

TDC points should be as follows:

[Exige]

7 hours ago, Adamw said:

Your TDC angles are wrong which means your spark is ~20 retarded on every 2nd cyl.   The TDC angles you have set are evenly spaced 72 deg apart which would be an even fire engine - you would need a block with a 72deg vee for this to work.  

The viper block is a 90deg vee, so when coupled with the shared crank pins that are 72deg evenly spaced you end up with odd firing angles 54 & 90deg apart.  

TDC points should be as follows:

I have already tried that before i switched 72 degree one, it ran exactly the same no improvement so i tried both. None works

left side is still red and hot. Only thing that affected was i set injection timing to 470 instead of 340 and it got better a bit

[Electredge]

7 hours ago, Adamw said:

Your TDC angles are wrong which means your spark is ~20 retarded on every 2nd cyl.   The TDC angles you have set are evenly spaced 72 deg apart which would be an even fire engine - you would need a block with a 72deg vee for this to work.  

The viper block is a 90deg vee, so when coupled with the shared crank pins that are 72deg evenly spaced you end up with odd firing angles 54 & 90deg apart.  

TDC points should be as follows:

In the help section it says these Custom TDC Points need to be in the firing order. If I'm understanding that correctly I think it would look like this. 

 

1 = 0

2 = 630

3 = 288

4 = 198

5 = 432

6 = 342

7 = 576

8 = 486

9 = 144

10 = 54

Sorry not on my tuning computer and don't have the software on this machine

Let me know if that looks right Adam

[Adamw]

2 hours ago, Electredge said:

In the help section it says these Custom TDC Points need to be in the firing order. If I'm understanding that correctly I think it would look like this. 

The table I posted is correct, it is from an engine I set up and tuned a couple of years ago.   

The note in the help file is referring to the numbers across the top of the table.  So cell 1 is the angle that the first cyl fires at, cell 2 is the angle that the 2nd cyl fires at, etc.

 

3 hours ago, Exige said:

I have already tried that before i switched 72 degree one, it ran exactly the same no improvement so i tried both. None works

left side is still red and hot.

Did you do a power cycle each time you changed?  What is your trigger offset set at - I remember it was difficult to set the base timing on these since you get one flash that is correct then the next flash that is wrong.  

[Exige]

On 3/28/2021 at 10:55 AM, Adamw said:

The table I posted is correct, it is from an engine I set up and tuned a couple of years ago.   

The note in the help file is referring to the numbers across the top of the table.  So cell 1 is the angle that the first cyl fires at, cell 2 is the angle that the 2nd cyl fires at, etc.

 

Did you do a power cycle each time you changed?  What is your trigger offset set at - I remember it was difficult to set the base timing on these since you get one flash that is correct then the next flash that is wrong.  

oh yes, on this car you can not start engine without power cycle.

my current base timing offset is now 0

trigger wheel is 60-2

when i crank engine and set base timing yes one flashes correct another flash is off.

when engine is running  flashlight is flashing at 0 on cyl1 (TDC)

 

[Exige]

 Only thing that affected was i set injection timing to 470 instead of 340 and it got better a bit

[Adamw]

8 hours ago, Exige said:

my current base timing offset is now 0

trigger wheel is 60-2

These engines dont normally have 60-2?  Is is an aftermarket wheel?  What trigger mode are you using?  What pattern is on the cam?

Zero seems like an odd offset?  When the engine is at TDC#1, is the missing tooth gap right underneath the sensor?

 

7 hours ago, Exige said:

Only thing that affected was i set injection timing to 470 instead of 340 and it got better a bit

It is not related to injector timing.  Fuel will happily sit in the intake port until the next time the valve opens.  If you have red pipes then ignition timing is very retarded, combustion is happening closer to when the exhaust valve is open.    

[Exige]

here is file and log that i took today. please check and advice. 

idle left side is rich, free rev it goes leaner, at the end manifold gets red hot only on left side

 

base.llg Base_test.pclr

[dx4picco]

What is your trigger system? 

[Exige]

Just now, dx4picco said:

What is your trigger system? 

crankshaft 60-2
camshaft trigger Stock Viper 8.3
 

[dx4picco]

Maybe add a trigger scope to the files you posted so Adam can have all the tools. 

Are you sure that when you said that 1 bank is at 0 it corresponds to the mechanical tdc and not some unprecise markings? 

[Exige]

5 minutes ago, dx4picco said:

Maybe add a trigger scope to the files you posted so Adam can have all the tools. 

Are you sure that when you said that 1 bank is at 0 it corresponds to the mechanical tdc and not some unprecise markings? 

i have pulled cylinder 1 piston all the way up to TDC, marked crank pulley and front cover so i know where TDC is, then checked with timing light and set base ignition timing that way

triggerscope logs

Trigger Scope Log 2021-03-30 2;59;19 pm.llg Trigger Scope Log 2021-03-30 2;59;59 pm.llg Trigger Scope Log 2021-03-30 3;00;08 pm.llg

[Adamw]

For checking base timing, I would temporarily set it to direct spark, unplug all coils except #1 and confirm timing while cranking.  This will get rid of the second flash which makes it hard to do it right.