Corvette C5 Vortech misfires

[Hocky]

I have mounted a A&A Vortech supercharger on a Corvette C5 2001.
Been on the dyno last year and a couple of days ago.
LS6 Engine has a Fast intake, headers and a bigger throttle and MAF.

The engine is running fine and makes good power up to 5300rpm. Then its missfires at different cylinders until 6000rpm. Most common is that its one cylinder misfires.
This symtom was the same both last year (5psi) and now (8psi).
Engine did not have this symptom before supercharger install.

Engine makes 490hp @6080rpm and 605Nm@5170.
Missfires comes just after the max torque.

Tried this:
- New sparkplugs with different gaps down to 0,017"
- Tried a known working coil packs including cables
- Upgraded fuel system, now Racetronix pump and MSD 2351
- Compression test was made and all cylinders where around 10
- Different AFR tested but is now around 11.5

I was not mapping the engine myself but the tuner had HP tuner doing it so I was not totally lost.

Any ideas of what this can be?
Maybe something strange in the tune, something going over the limit or something? I have not found anything.

Can it be the ecu itself?

The tune is attached to this post if someone with a good eye can catch anything.

Sorry no log files but Ill try to get some.

This is really really frustrating so I am glad for any help!

[c5mtl]

I have mounted a A&A Vortech supercharger on a Corvette C5 2001.
Been on the dyno last year and a couple of days ago.
LS6 Engine has a Fast intake, headers and a bigger throttle and MAF.

The engine is running fine and makes good power up to 5300rpm. Then its missfires at different cylinders until 6000rpm. Most common is that its one cylinder misfires.
This symtom was the same both last year (5psi) and now (8psi).
Engine did not have this symptom before supercharger install.

Engine makes 490hp @6080rpm and 605Nm@5170.
Missfires comes just after the max torque.

Tried this:
- New sparkplugs with different gaps down to 0,017"
- Tried a known working coil packs including cables
- Upgraded fuel system, now Racetronix pump and MSD 2351
- Compression test was made and all cylinders where around 10
- Different AFR tested but is now around 11.5

I was not mapping the engine myself but the tuner had HP tuner doing it so I was not totally lost.

Any ideas of what this can be?
Maybe something strange in the tune, something going over the limit or something? I have not found anything.

Can it be the ecu itself?

The tune is attached to this post if someone with a good eye can catch anything.

Sorry no log files but Ill try to get some.

This is really really frustrating so I am glad for any help!

maybe its no help...but i had the same broblem and it turned out to be an arching spark plug boot that had been melted by my headers

[Hocky]

maybe its no help...but i had the same broblem and it turned out to be an arching spark plug boot that had been melted by my headers

I have changed all ignition parts with to known working parts with no success.
Anyone that had problems like this and found out that replacing the PCM was the solution?

[exploder]

replacing pcm is not going to fix it. you need to post some log files.

[98 tigershark]

Did you get the misfire problem fixed. If not check your fuel pressure under load What is the PSI at over 5300 rpms.
If it does that when you are hitting peak torque what is your INJ duty cycle?
Does it do it at the same rpm in every gear or a little lower rpm every gear?
Let me know. Also are you using a boost a pump?
98 tigershark

[98 tigershark]

What are size injectors, fuel pump and regulator are you using and at what PSI at what RPM. KPa 0, 8.81250
5,8.86719
10,8.92188 and on
So let me know if you are OK
Best wishes,
98 tigershark

Did you get the misfire problem fixed. If not check your fuel pressure under load What is the PSI at over 5300 rpms.
If it does that when you are hitting peak torque what is your INJ duty cycle?
Does it do it at the same rpm in every gear or a little lower rpm every gear?
Let me know. Also are you using a boost a pump?
98 tigershark