Help with Tune Review

[jpollard38]

Hello -

I'm new to HP Tuners and wanted to ask those more knowledgeable than I to take a look at my tune. I'm happy with my local tuner, but am looking to learn and understand more about my car and the tune specifically. The car is a 2009 G8 GT, stock motor, mild cam. At stop lights it occasionally shakes a bit and I've had to up the idle to around 750 to help reduce it as much as possible. Additionally, when cold, there seems to be very little vacuum as the brakes require a large amount of effort to engage. Finally, I'm seeing ~15mpg combined now where as I was seeing 20ish before the cam.

To be completely clear, I'm happy with the car, I would just like to learn more about the car such as why I'm seeing such poor mileage and am getting the shakes. If anyone could review my log and tune I'd love to start learning!

Thanks

[jpollard38]

While the tuner asked me not to share specifics on the cam, generalities might be helpful here. 23x/23x 59x/61x 115 LSA

[gn2beatu]

Form 3:00 to around 3:25 there are two differant idle areas where the O2's are doing opposite things. The first one is where the O2's hold for several seconds at 800mv + and the 2nd time they hold around 35mv for an even longer time. Both are similar RPM, INJ PW, and MAF. The only change was kpa from 55kpa to closer to 59kpa. Then right at 3:28 you go back to 55kpa and it goes rich and holds rich with no O2 switching. Have your tuner tweek the VE constants. Im betting those tables will need addressing a little more as your most likely at a breakpoint between two values in the MAP constants. Those tables have to be dialed in right when you have a bigger cam.

A second thought I noticed by ~5000 rpm your only at 45% injector duty cycle (bigger injectors?). What injectors are you running as its very important to have the inj tables correct. If your tuner missed that part, your goona have fits with the bigger inj at idle.

As a side note, get rid of the KR in the 1800-2000rpm areas and 4400-4800rpm areas, you have up to 3 degrees KR. Subtract the amount of KR from your timing table plus an additional 2-3 degrees (I would do three) as your running 29 degrees of timing above 4800rpm which is peak TQ and that is too high. In fact you where at 60% throttle while running 29 degrees of timing which means your load value at that RPM and KPA is going to be high, so Id tweak the whole timing table a tad in that area.

[BigDaddyCool]

I didn't look at the log per say but it looks a little hacked together....... eg. maf scale, low octane table still stock? max 2 degree's at wot for knock maximum?..... raised idle but left torque management controls..... can u upload your stock tune to compare?

Looked at the log now......... hmmm ve way out in the lower cells? I could give you some advice just to 'try' ....... in the high octaine table...... just hit smooth selection until it stops changing values, reflash and see what you think........ the reason I say this is because it will add timing in the lower map area's and may smooth our your rich condition......... its a quick way of doing things....... again just something to 'try' if you would like, it will help with idle stumble and just generally smooth out timing.

May or may not work..... either way, advice.