VN 5L Tune need help :(

[vn_ss_cm]

Hello Guys,

I have missed the boat in getting the nvram stuff. Can an expert please tune the current file to suit a VN 5L with the following mods.
I have tried but still learning and need the car to run. The attached tune has been running fine for years until I upgraded the intake.
Current issue is the 19 AFR's underload with missfire, 10 afr when idling warm and very low rpm cold start splutters abit.
Any help will be appreciated.

5L, Crane 276 deg Camshaft, VT V6 Injectors, edelbrock airgap intake manifold, 1200CFM throttle body, pace maker Extractors, twin cat system, 3inch exhaust,

[vlad01]

Going by the cam specs you will need bigger injectors. I would get at least the 36Lb L67 injectors the Vt v6 ones are only like 16Lb at 3 bar and about 19lb at 3.5 bar.

I maxed out my 20Lb ones straight away on my v6 with similar cam specs, I run 39lb ones and hit 65% DC so at 100% DC you will need at least 26LB so min of 30Lb to stay anywhere near the recommended 80% DC.

['quipt4it]

If the injectors are 0280 155 777 (VT), then they are 21.5lb/hr @ 3.5 bar. Around 19lb/hr at your reg. pressure of 3 bar. About the same as stock 5 litre.
Most say you can run 85-90% duty cycle with no worries. You would likely be exceeding that now. You can up the fuel pressure with an adjustable regulator to give you more flow (within limits), but this is a cheap work-around.
Can you describe exactly the dimensions of the exhaust at each point, ie cat, dual pipes, and is it single 3" rear/ single muffler.
I'm going over the tune now and I'll send it to you when I'm done.

[vn_ss_cm]

thanks guys I have ordered some l67 ones if you dont mind make 2 tunes one for the ecotec 777 and l67 pretty please.

its 2.5 inch from extractors to twin 2.5 inch 200cell cats merged into a single 3inch all the way to the back.

['quipt4it]

PM'd the 1st tune.
The 3" single will flow less than the duals. It is effectively the size of the whole system.

[antus]

It sounds like people are going to have a go, but it'll all be some level of guesswork if you dont post any logs and they cant see whats happening now to work from there.

Unless they just start from scratch and send you a 12P tune, which would be the obvious next step. You can still get an nvram, contact gareth.

['quipt4it]

There is nil stock, plus anything is better than the tune DS was using.
Added:

...I have tried but still learning and need the car to run...

[antus]

There is more stock now.

['quipt4it]