I'm currently running a procharger with 10lbs of boost, 42lb injectors, and the 90mm lightning mass air meter. I have a tune from Mike at Troyer Performance. My question is what kind of timing advance should be in my program?

When I do my datalogging in second gear with my street tune my timing advance runs around 14.5 to 15. When I did a datalogging run in third gear with the same tune, the timing stayed around 10 to 11.5. Is there room for more timing in the program?

I know I will eventually talk to Mike but sometimes it is hard to get in touch with him. I was just wanting other's thoughts.

 

I ran 12-14 on mine but I had 93 octane also...if you only have 91 octane then I wouldnt go over 12 degs

 

Hi Jason,

I *thought* that was you - as you know, we have not seen any data from you since back in February, and didn't know until today that the A/F's & fuel trims are now where they need to be from our last change. It's nice to be able to datalog everything including A/F's any time you want after all this time, the multiple blowers, etc., eh?

The A/F's have to be done before we will finalize the high gear (highest load) timing numbers, so where we are right now is, as of our discussion today, we now know that the A/F's & fuel trims are right where they should be - now we need to see your current data so we can see just exactly what it's actually doing timing-wise in the different programs, at the various load & rpm points (and gears) as we discussed. Then we can evaluate for just how much additional timing it will tolerate with your particular configuration & local fuel quality with the supercharger pumping 10 PSI of boost on the stock pistons. We always finalize the blower tune timing #'s once the MAF transfer function is nailed - tuning 101.

By now we've had a chance to talk and go over all of this in detail of course (and great talking with you again, as always), so we've covered how the increased loading of being in the higher gearing is going to cause load to go way up, and thus timing to drop from what you see in the lower gears - this is something that we *always* do that in our "baseline" blower tunes so we can make certain that engine is going to be safe for you to get the datalogging done & that info back to us. If the vehicle were here, all of that would be done within a couple of hours of course, but when we have to wait for data, it takes more time to get the tuning finalized.

Based on what we discussed, sure - it sounds like there should be room for more timing up at those highest load points, and we'll be happy to do that once we see the data. That will bring peak power up in the higher gears like it is in the lower gears, so that it pulls nice at high speed. I look forward to seeing your current data so we can get the additional timing added in, and we'll also take care of the gear ratio change you'll be doing since you want to drop back from the 4.10's to the 3.55's for the increased highway driving you will be doing, to get mpg maximized.

As always, good talking with you, Jason - and congratulations on your upcoming graduation later this year, by the way - you've been working hard for your degree for most of the time we've worked with you over these past coupla-few years thru your truck's various configurations, etc.

We'll look at your data & then finalize your blower tuning for you, & talk to you soon!