14 Challenger RT cam tuning help (Spark)

[iEggsy]

Im needing help find out where idle underspeed/overspeed adaptive spark tables are... I have a Comp 274 cam and im currently trying to get the spark to become more rough at idle so it brings out the cams lobe... I've done everything from adjust idle to 600, then bumping it up by 50 per tune, ended up calling it quits and just going to keep the idle at 7-800..

Another issue im having is my RPMs jump rapidly 25-50+/- while idling, im kinda new to the whole HPTuners thing but im sure trying my best to figure it out, if someone can point me into the directions of the Idle Adaptive spark controls for underspeed/overspeed spark that would be awesome.. I'll post my tune so you guys can look at it




Full setup: BBK Tuned length headers, upgraded BBK 90mm throttle body, Cat/Reso/Muffler delete, Comp 274 Cam (w/ Phase Limiter), CAI, and a few other minor things that doesnt relate to the engine.. Im trying to get everything worked out before throwing my supercharger on, Ive ordered a Dragon Claw clutch with a lightweight flywheel, and im debating on getting underdrive pulleys for the time being

[iEggsy]

CAM ESP Test New (P2174 Fix).hpt

Trying to get an aggressive idle chop

[coanan]

Are you getting that idle movement with A/C on? Mine does this when A/C cycles, turn it off and it's stable. Probably some setting I haven't adjusted correctly.

[iEggsy]

Yea, its occurring with the A/C off! I haven't tested the RPM +/- with the A/C on, ended up noticing that over the weekend when I was tuning at a car show

[kenandjenn4551]

I have my idle set for 752 rpms with my custom grind. 224/230 112.5 LSA, so slightly more aggressive than the 274.

The key is getting the idle airflows correct.. otherwise, everything fights each other.

Once I got the airflows right, I was able to completely remove all idle throttle torque up to +/- 500 rpms.

For spark, I have very small numbers for derivative. I can't remember my exact proportional numbers, but I'll look when I get home.

My idle doesn't noticeable surge, but ranges from 650-750 rpms. I have minimum spark set to 1*, so spark swings from 1* up around 18*.

Since spark is controlling my idle, I get a nice consistent chop.

I wish the idle didn't dip quite so low, but it is hard to raise the idle up without throttle torque input.

If your airflows are too high, it will raise idle up, but your lope won't be as rhythmic. Get ready to spend many hours getting it perfect.

[kenandjenn4551]

Also, make sure your minimum idle set points are well below your desired idle set points. I also set all my desired idle tables to 752 rpms, except reverse which 824 rpms.

The 675-750 rpm range really is the sweet spot, as the chop lengthens and deepens. In the real world, our cams aren't very big so this about as good as you can do.

[Homer]

FYI - nice writeup on getting airflow setup.

https://forum.hptuners.com/showthrea...Table-Tweaking

[Jay@HAP]

I would put your spark PID's back to stock and play with the T/B airflow.

[kenandjenn4551]

I agree with starting back with stock values. You can then dial them out gradually to free up some natural cam rhythm.

[iEggsy]

I ended up putting a new clutch in witha lightweight flywheel by Hays, it was there 26 spline rated for 1200ft-lbs of torque... Lobe is pretty noticeable now, although it only apparent for a few seconds after stops.. I believe its my idle speed, because it drops some when i come to a stop, roughly around 700-725 then surges back to 750 where the tunes set up at... Im lowering it down to 696 like the rest of my Engine Run Times are.. Should I disable BARO LEARN to tune some of the graphs or just keep it off in general?

Im about to have this guy I know with an 1800hp S10 tune it and see what he can get done, so it might be worth it if i cant figure it out

I think the airflows are whats off with me installing that bigger TB, went from the stock one to a 90mm and never adjust airflow because spark is fighting the idle imo plus Comp 274's a hard cam adjust