First Time Tune Review Request: 91oct LQ9 with BTR Stage3 V2 cam and 1.75" long tubes

[arbartz95]

Hi all,

Finally got my truck about where I think I want it. Have a few small things to iron out (return to idle could be slightly better, but it isn't terrible), but for the most part, my fuel trims are all within 3% and she seems to be running well.

All of that being said, I'm obviously a DIYer, and don't have access to a dyno (I know I could take it somewhere and get it tuned by a pro, but what's the fun in that?). So, I'd like to see if any of you fellas here would mind giving it a quick look over to see if there's any glaring issues or no-nos. 2004 Chevy Silverado SS - PCM - Trans - v3.0 - Eng - v2.0_SD.hpt

One of the big things that I'm just plain not sure of is ignition timing, and I know it's the easiest place to send my rods packing.
2021-11-29 21_25_57-.png

Compared to the stock timing map, I've been able to add a pretty good amount of timing at WOT without seeing knock. I was just adding a degree or two at a time, then doing 3 back to back 2nd gear pulls from 2500RPM with the converter locked. However when I did a full pull from a dig and let it shift I felt the torque take a nosedive as it approached 6000RPM and beyond. Then it would grab 2nd gear and pull hard. Looking at the logs I realized that the timing falls off at higher RPM quite a bit. Even though I'd been adding timing, I'd been doing it across the whole range of WOT, vs adding more at higher RPM.

So, I "flattened" out the curve. I always thought timing was supposed to rise with RPM and drop with load. So I now have a "flat" timing map at WOT, and I feel like that is sub-optimal, but just plain not sure.

Any insight is greatly appreciated! Just a hobbyist here looking to learn more.

Oh, and here's the specs:
2004 Silverado SS AWD
Stock LQ9, except for BTR Stage 3 Truck Cam v2 (218/224 .553/.553 110+0), with valve springs to match
Unknown CAI (came with the truck), but I put a new K&N filter on it
DynaTech SuperMaxx 1.75" Long Tube Headers w/ 2.5" Catless Mid Pipes
Summit 2500RPM Stall Lock-Up Converter
Mildly built 4L65E

Thanks!

[5FDP]

You gotta be way out of fuel injector aren't you?

With how high you have your VE table and how small those injectors are, you are likely pushing well past 100-105% injector duty cycle.


The PE enable settings are still stock, you should change that up too. Raise the MAP kpa to 80kpa, lower the enable torque to 50%. Lower the RPM delay to 1,500rpm and lower the pedal enable to 65%. I'd also lower the EQ ratio to 1.200 in the upper rpm instead of 1.230, it shouldn't need to be that rich.

I'd turn off the engine side abuse mode as well and max out the burst knock enable delta table so burst knock doesn't get in the way when you floor it.

[arbartz95]

Oh yes, certainly out of injector, should've mentioned that. Was creeping up to 0.950 lambda at 6500RPM. I just ordered a set of these and they should arrive on Wednesday. https://deatschwerks.com/products/35...369ef4bf&_ss=r

I will change up those PE settings, but just for my education, why should I make those changes? I can get leaning it out a tad. 0.813 lambda seemed awfully rich. Was thinking 0.850 seemed more reasonable.

Good to know on the abuse mode stuff and burst knock. Thanks!

[blindsquirrel]

The reverse drum on 60/65/70E's likes to fling itself apart if you go above 6K in first gear. It spins at 3x crankshaft speed in 1st, then has to come to a complete stop in less than 1/2 a second when the band applies for 2nd gear. The lower your 1-2 shift RPM the longer your trans will survive.

reverse drum.png

[arbartz95]

Well, I don't want that to happen... I'll drop that shift point for 1st gear to 6k then.

Is this something that upgraded parts exist for that can handle higher 1st gear shift speeds? Looking forward to when I need to get a more serious build when I go turbo.

[blindsquirrel]

There are aftermarket gearsets that drop 1st gear to 2.84:1, which helps some but is a lot of money. The easiest way to fix all the 4L60E limitations is to stick in a mildly built 4L80E.

[kevin87turbot]

Well, I don't want that to happen... I'll drop that shift point for 1st gear to 6k then.

Is this something that upgraded parts exist for that can handle higher 1st gear shift speeds? Looking forward to when I need to get a more serious build when I go turbo.

Blindsquirrel is correct about the likelihood of the drum being damaged by continuous high rpm use. However, there are a few applications that shift up to 6400 rpm in stock applications...(look at the 2005 Corvette and the TBSS applications.)

I've got a couple of customers that like to live on the edge. I just tell them of the likely long-term consequences and let them make up their mind. One of my customers has the quickest NA Silverado SS. He likes it to shift at 7500+ rpm! It's amazing that the 4L65E holds up in that application, but it does.

[arbartz95]

@blindsqurrel, I am aware of the 2.84:1 gearset (I believe from Sonnax, right?), but yeah seems like a lot of money for a fully built 4L60 vs just going 4L80. Just somewhat equally expensive and a pita to keep the AWD with the 4L80. I don't even know if people are still making the special input shaft adaptor.

@kevin87turbot, that is good to know that there are stock applications which shifted higher than 6k. I figure I'm never spending a lot of time up there, it's just a quick 1-2 shift, not really hanging on the limiter or anything.

That's nuts to hear he's shifting at 7500RPM! I didn't even think the pump inside would handle that.

[DougO]

They make the adapter, I kept my AWD