[holdinslab]

Anybody have the secret sauce to getting a Procharger and cam combo to idle decent without to much rpm surge. I have tired rescaling the airmass tables and maf to reduce the torque commanded but it seems to be good one day and back to the same surge the next.

Car has Btr Blower cam, p1sc1 Procharger 10lbs, lt2 intake baro breakout, headers, full bust bottom end, monster clutch triple disc clutch m6... working with hptuners

[Joshinator99]

Originally Posted by holdinslab

Anybody have the secret sauce to getting a Procharger and cam combo to idle decent without to much rpm surge. I have tired rescaling the airmass tables and maf to reduce the torque commanded but it seems to be good one day and back to the same surge the next.

Car has Btr Blower cam, p1sc1 Procharger 10lbs, lt2 intake baro breakout, headers, full bust bottom end, monster clutch triple disc clutch m6... working with hptuners

Needs a tune by someone who knows what they’re doing. A cammed Gen5 LT engine is a tough one to learn on. MAF is just the tip of the iceberg, VVE and VT tuning is critical to getting a cammed LT to idle and drive well.

[JimGnitecki]

Originally Posted by Joshinator99

Needs a tune by someone who knows what they’re doing. A cammed Gen5 LT engine is a tough one to learn on. MAF is just the tip of the iceberg, VVE and VT tuning is critical to getting a cammed LT to idle and drive well.

That was SO politely said! And hopefully he will listen.

Jim G

[holdinslab]

I built the car myself , just not much of a tuner. trying to learn. that's the only way right? thanks for the help though.

[Joshinator99]

Originally Posted by holdinslab

I built the car myself , just not much of a tuner. trying to learn. that's the only way right? thanks for the help though.

This is a very tough platform to learn to tune on. Watch Greg Banish’s Calibrated Success videos if you want to try to understand this better.

[LT1ornothing]

Originally Posted by holdinslab

I built the car myself , just not much of a tuner. trying to learn. that's the only way right? thanks for the help though.

Agreed with the other guys, let a good LT tuner take care of the tune. You got Jeremy Formato and Howard Tanner relatively local to you.

[SOCAL.M6.ZLE]

Originally Posted by Joshinator99

This is a very tough platform to learn to tune on. Watch Greg Banish’s Calibrated Success videos if you want to try to understand this better.

Great advice.

[JimGnitecki]

holdinslab: You can do serious harm to your engine "learning" how to tune. Worth the risk?

Jim G

[KingLT1]

VTT and VVE more then likely need work.

[cjperformance]

Originally Posted by holdinslab

Anybody have the secret sauce to getting a Procharger and cam combo to idle decent without to much rpm surge. I have tired rescaling the airmass tables and maf to reduce the torque commanded but it seems to be good one day and back to the same surge the next.

Car has Btr Blower cam, p1sc1 Procharger 10lbs, lt2 intake baro breakout, headers, full bust bottom end, monster clutch triple disc clutch m6... working with hptuners

Being a learner myself, my suggestion would be to get a "base tune" from a remote tuner, and finish dialing it in yourself.

The base tune will get you in the ballpark, then you can make incremental changes yourself and see how things respond.

[KingLT1]

^That's the only way to go. It's how I started. It all comes down to putting in the time and effort to learn this stuff.

[holdinslab]

I have gotten a base tune from a well established tuner already. I have recently moved to a different part of the country and the car is acting funky on cold starts. VVT goodies have been deleted on the car and I'm not completely lost, just trying to get some thoughts from others.

[KingLT1]

Maf is used for fueling not torque control. The Virtual torque tables are referenced for torque modeling and controls idle spark. Need to be logging spark and see what it's doing at idle.

Basically, you need to fail the maf, tune vve, turn maf back on, tune maf, then get the torque modeling correct in order to get sufficient idle spark. Then if it still surges you likely have something else going on.

Goat rope garage has some fairly decent YT videos on MAF, VVE, and VVT tuning for Gen 5 LT.


*If I had to guess, your base tune might have the minimum spark table cranked way up to get the idle spark in range and it's fighting the torque tables which will cause the engine to surge. The is common LS tune methodology that doesn't work on LT engines. I never raise minimum spark higher then 4-5 degrees in the 4-800colums and that is only so the trans shifts with more timing. Again, the proper way to get correct idle spark is go into the Virtual torque tables and pull torque in the idle areas for the timing tables up to 10 degrees only... pulling torque will increase timing. Adding torque will reduce timing.

[JimGnitecki]

Originally Posted by KingLT1

Maf is used for fueling not torque control. The Virtual torque tables are referenced for torque modeling and controls idle spark. Need to be logging spark and see what it's doing at idle.

Basically, you need to fail the maf, tune vve, turn maf back on, tune maf, then get the torque modeling correct in order to get sufficient idle spark. Then if it still surges you likely have something else going on.

Goat rope garage has some fairly decent YT videos on MAF, VVE, and VVT tuning for Gen 5 LT.


*If I had to guess, your base tune might have the minimum spark table cranked way up to get the idle spark in range and it's fighting the torque tables which will cause the engine to surge. The is common LS tune methodology that doesn't work on LT engines. I never raise minimum spark higher then 4-5 degrees in the 4-800colums and that is only so the trans shifts with more timing. Again, the proper way to get correct idle spark is go into the Virtual torque tables and pull torque in the idle areas for the timing tables up to 10 degrees only... pulling torque will increase timing. Adding torque will reduce timing.

That was nice of you, KingLT1.

Jim G