I thought it linked, had to repost with the link. Its call BC or Bluecat Transmission software. I picked up a copy of HPTuners website. You can either join the forum and download the file or I can send you the file later this week.Originally Posted by Scrufdog
Got it. I'll see if I can figure it out and go from there. I take it from this little piece of software, that its fairly common for GM transmission shifting/lockup to be based on MPH as opposed to the more logical RPM?
1995 Chevy C2500 Suburban 5.7 4L80-E, 16197427, BNKM, $31
Hooker Long Tubes headers, dual 2.25" exhuast, mufflers. TBI mods, Moates APU1, TunerProRT, CAI, 4 core radiator
MPH is actually very logical and easy once you get the hang of it. Compared to output shaft RPM that Chrysler uses it is a walk in the park. WOT is the only shift points that use RPM.
Life gets busy....
Messing with this tonight a little bit. Having never used BlueCat before I think I got it worked out. Here's a screenshot of what I worked out with BlueCat vs. my stock tables.
What do you guys think?
...... EDIT
Might need to make it bigger, let me know...
1995 Chevy C2500 Suburban 5.7 4L80-E, 16197427, BNKM, $31
Hooker Long Tubes headers, dual 2.25" exhuast, mufflers. TBI mods, Moates APU1, TunerProRT, CAI, 4 core radiator
ok, bigger
1995 Chevy C2500 Suburban 5.7 4L80-E, 16197427, BNKM, $31
Hooker Long Tubes headers, dual 2.25" exhuast, mufflers. TBI mods, Moates APU1, TunerProRT, CAI, 4 core radiator
Drop the minimum RPM down to about 1200 rpm and drop the accel gear to 3rd.
Earlier in the thread you said to set the lockup to 1800-2000 RPM, thats why I put it at 1800, how come the change of recommendation?
Also, the little mouse over for Accel Gear mentions that 4Lxx transmissions are generally recommended to leave the Accel Gear at 4th gear. I assume you go with 3rd gear to retain lockup while accelerating in 3rd, something like a tow tune?
Trying to learn
Thanks
1995 Chevy C2500 Suburban 5.7 4L80-E, 16197427, BNKM, $31
Hooker Long Tubes headers, dual 2.25" exhuast, mufflers. TBI mods, Moates APU1, TunerProRT, CAI, 4 core radiator
Because for some reason I kept thinking 4L60E. The 4L80E converter on newer trucks even gets locked in 2nd at WOT. The 4L80E is more efficoemt with a locked converter or I should say takes a bigger hit that the 60e does with an unlocked converter.
ok, so with my 1995 4L80-E, keep the lockup low, shift points slightly delayed (higher RPM/MPH to help that 1600RPM lug) ... should I set it to lock in 2nd or stay wit 3rd gear lockup?
1995 Chevy C2500 Suburban 5.7 4L80-E, 16197427, BNKM, $31
Hooker Long Tubes headers, dual 2.25" exhuast, mufflers. TBI mods, Moates APU1, TunerProRT, CAI, 4 core radiator
That is where you can play with the settings to find what works best for you. I was using 1800 rpm mininum, but found some situations where it cause a slightly delayed, harsh upshift. Your TBI engine will be happier running in the lower RPM ranges than my cammed vortec is. I personally like locking it as early as 2nd gear, accel lock, but no two drivers or vehicles are alike. If your engine had a larger cam, I would say stay unlocked longer and shift a touch earlier, but stock cam seems to like the opposite.
Im gonna start with this one here, and see how it feels and acts. When I drop the Accel Gear down to 3rd, it shows that it wont engage 4th gear until 53 miles per hour minimum and increases from there. Seems a little high, might try it out at some point though. Opinions?
1995 Chevy C2500 Suburban 5.7 4L80-E, 16197427, BNKM, $31
Hooker Long Tubes headers, dual 2.25" exhuast, mufflers. TBI mods, Moates APU1, TunerProRT, CAI, 4 core radiator
not bad, first gear felt great, but never felt the TCC kick in during around town driving, I usually would. The 'Lug Spot' was still there. Messing with this and talking to you guys gives me a better understanding of whats going on. I think I'm going to start back off with the stock shift tables and hand tweak them up from there, using BlueCat as a general guide.
Thanks for the help. I'll post back at some point with some results.
....
While your listening... whats the Line Pressure Modulation Time vs. Shift? 1 --> 2 and 2 --> 3 are 4 seconds and 3 --> 4 is 2.1 seconds. How does this effect shift times, or is it for something else?
1995 Chevy C2500 Suburban 5.7 4L80-E, 16197427, BNKM, $31
Hooker Long Tubes headers, dual 2.25" exhuast, mufflers. TBI mods, Moates APU1, TunerProRT, CAI, 4 core radiator
With the settings you are running you will never get 3rd TCC unless you have the shifter in 3rd. The 3-4 shift points are at a lower MPH than the 3rd gear TCC lockup. You can play with the slope, offset, up(shift), down(shift), accel and cruise lock gear, etc with BlueCat. Never have liked the stock GM shift/TCC settings, always found them attrociously horrible with the 4L80E.
Been some time since I have played with the 0D and OE masks so I would have to look at the hack and code to see what that does exactly. Probably helps control pressure ramp of the EPC during the shift.
If you want OD to engage earlier, need to drop the minimum RPM lower.
So this is what I ended up with, that I'll upload and try tomorrow.
Started with the stock tables, left the top end stock, since in the engine's current form, no more RPMs are needed. Bumped up the speed for all shift points and smoothed it out. I checked the timing retard spot I was hitting and I think I got it just right to downshift in that area instead of lugging out. Will tweak as needed.
1995 Chevy C2500 Suburban 5.7 4L80-E, 16197427, BNKM, $31
Hooker Long Tubes headers, dual 2.25" exhuast, mufflers. TBI mods, Moates APU1, TunerProRT, CAI, 4 core radiator
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