Scale tune or lower timing in last cells?

I have an 85 foxbody with a 5.3 out of a 2001 Silverado with ls6 cam 80lb injectors and on3 7875 turbo currently running 7 psi. OLSD Tune. I recently bought the car and it was tuned on pump gas and I have switched it over to e85 and have been tuning it. The Car runs good as is but Im about ready to turn the boost up and make some more power but I noticed in my log the the timing table grams/cylinder is maxed out. Ive done some searches and read a bunch of threads and it seems like people are re scaleing the tune or just running low timing in the 1.20 cells at the bottom of the table. Which is better to do? Also Could You guys have a look at my tune and datalog and tell Me what You think I could improve on. Thanks in advance!

I just set my timing in that last row. It's where you will spend all the time anyway once you hit full boost. It's working fine for my 5.3 on E85

Ron

Scaling will get you the most control over timing. Leaving it in that last row doesn't allow you to tune for pressure variations.

Pressure variations? Like Baro? I'm looking to bump the boost up to 700hp or 20psi which ever comes first

I'm right at 700 wheel if I calculate backwards from 146 mph @ 3400 lbs.
I'm at 15 psi.

I'd be interested in scaling if there were a detailed process to do so. I haven't found that online. Just general comments like oh it's easy....

Sounds like your car/tune is working great! I wouldn't change it. What timing and afr are you at? Car to post your tune?

I've stayed conservative. 16 deg timing and 11.1 AFR. Car became a handful due to something in the suspension. That is all rectified now, just waiting on weather. I never got a chance to try a little leaner or mess with timing.
Shoot me a PM with your email and I'll send you the tune.
Injectors are ID1000 btw at 56 psi base pressure.
I've dataloged every pass, and AFR follows commanded very nicely.

Quote:

---

Originally Posted by pyro719

Pressure variations? Like Baro? I'm looking to bump the boost up to 700hp or 20psi which ever comes first

---

By pressure variations, he meant like if different conditions make you hit different boost. The engine will do better with more timing when there's less boost, but needs to have less timing with more boost. A turbo setup can make boost without being at full throttle, and boost can come in at different RPM's. Plus weather and altitude can affect the boost. Or if you did something as simple as adjust the boost controller for more boost.

Gm/cylinder timing table is maxed out at 7psi so that should be a problem

Anybody have a write up on scaling?

This is a good reference/starting point:
http://injectordynamics.com/wp-conte...SteckScale.pdf

The main thing to understand is that anything that references air mass or air flow has to be scaled down with a few exceptions.

I've read that. Is the gen 4 stuff the same as gen 3 ? Do you have list if parameter s that need to be changed?