Okay, so I'm a little confused with some things on my most recent logs. First, heres a log:
Now what I'm confused about is if you look at the RPM, it peaks, then the tranny shows it shifts (4t40e), RPMs dip a hair and go back up, then timing is pulled and the RPMs drop. My guess is that when the RPMs drop is when it actually shifts. So that means the entire time from when it shows it shifts up to when the RPMs drop significantly, the tranny is slipping? Or is it something else? I assume the timing drop is for when it shifts, but I don't understand why the timing wouldn't drop as soon as it shows it shifts. Why the delay? You'll also notice I get a spike of knock right after the timing drops. It may be phantom knock because it does sound like its bouncing off the rev limiter (although it doesn't appear to based on the logs) when it shows those spikes. Or maybe it is real knock... again, not sure. I did lean out in 3rd and 4th gear a little on this run which explains the persistent knock in that area. (alternator died so the fuel pump voltage was dropping). How do you speed up the shifts? I have shift time set to 0 in the 300-320ft lb columns. Pressure max is 90. In the 320ft lb sift pressure columns, 1st to 2nd is set at 88, 2nd to 3rd set at 60, and 3rd to 4th at 88. Wondering if I should raise those the 90 or maybe even up the 90 max up? This run thats logged here had the B&M shiftplus on. With it off, shift pressure was lower (not maxed out at the 35
throughout the WOT pull.
12.6 @ 114.6 MPH
Start by getting rid of thre shift plus.....
P&P Tuning
420.5whp / 359.8wtq
Alright, will do. How do I raise the shift pressure enough to ensure a good shift under boost? With it off, the pressure will sometimes be less that the "35%" it maxes out at when its on. I'll go ahead and completely remove it though. The max pressure is at 90, should I raise it as well as the shift pressure tables? Just to help me understand the logs, when the RPMs do as they did in the pic, is that from the tranny slipping or something else?
12.6 @ 114.6 MPH
This is all from a lot of reading and suggestions from other 4T40E, 4T45E, and 4t65E owners....and looking over their tunes. I have only did small tweaks with my cav currently, and plan on doing more tuning to the trans soon.
Auto Shift speed > Do not mess with anything in any of these tabs unless you raised your rev limiter, and can rev higher. This can make your car not want to shift at all.
Auto Shift speed > Full throttle shift speed > normal & hot > If you did raise your rev limiter you need to start changing this. There is an excel spreed sheet on HPTuners that someone made to help with this. Getting this right is a major pain in the ass, and seems a lot like trial and error, than at X RPM you shift at X MPH. It is not black and white at all...
Auto Shift speed > Full throttle shift RPM > norma & hot >THIS HAS TO BE SET in-conjunction with shift speed. If it is wrong you effectively will not have a rev limiter!!!!!!!!!!!!!!!!!!! Personally I like to make the fuel cut off for the engine about a 1000-1500rpm more than the max of this. Just to be safer and you start over revving to hell. Also, do not forget what your spark RPM limiter is set to. I feel better with it set lower than fuel. Some set it the same as fuel. anyway....
Auto Shirt Properties > General > Force Motor Current > Everything I have been told and everything I read it do not raise the force motor current. 4T65E owners that do, end up killing solenoids. Some how ever play with the final right column and max it out. I personally haven't messed with this, and the 4T65E people say to leave it alone.
Auto Shirt Properties > shift time >Normal > Some people leave this alone, and some people scale this down. I see no reason to mess with this. I normally either drive like a normal person, or a complete asshole.
Auto Shirt Properties > shift time >performance > This can be set to all zeros', but some j-bodies just do not like this. And will start to not shift correctly. Normally setting this to zero is fine. The trans can only shift so fast though. I believe $t65E owners like either .1 or .01 sec. as the fastest it can shift.
Auto Shirt Properties > shift pressure > normal Some people scale this up more to the max pressure of 90. So effectively they are all full line pressure sooner in each gear. Some just leave it alone. Being boosted I would scale this a little.
Auto Shirt Properties > shift pressure > performance In other applications people would scale this up like they do with the normal one. On J's it is zeroed out. No idea why, and haven't messed with it.
Auto Shirt Properties > shift pressure > Max pressure Most people leave this alone. Some with build transmissions bump it up to the max. Honestly I couldn't tell a difference at max or at it current setting of 90.
Auto TCC > apply/release speed> Normal & release: I need to do more research on this. A lot of people change these if they have a higher stall converter. I got nothing, but I need to learn more since I have a 3000 RPM yank.
Auto TCC > performance > performance: Most people like to scale this up, but I have no other insight on this....
Torque Management > Abuse mode....This is were no one agrees. Some just simply turn it off. Some leave it on. I say leave it on. It is there for a reason!
Torque Management > Torque reduction > Most people zero this out...effectively removing it. I am more conservative. I feel better taking 25%-50% off of it.
Torque Management > Reduction Duration...The people that zeroed out the reduction above, zero this as well. At 100-111 degrees some people lessen / scale this to zero to the max temp setting.
Torque Management > Torque reduction > Normal...Most people zero this out...effectively removing it. I am more conservative. I feel better taking 25%-50% off of it.
Torque Management > Torque reduction > Performance...Most people zero this out...effectively removing it. I am more conservative. I feel better taking 50%-75% off of it. Re-flash might have this set to zero already...
I'm sure I missed something. If anything doesn't make sense I'll try to explain better. All the above is my opinion.
Added: Traction control can start messing with all of this. I recommend killing it while tuning these settings. My plan is to try and have mine come on above my stall encase I start spinning, but I'm not sure if this is practical at all yet. I need to do more research.
Ryan your thoughts?
Edited 3 time(s). Last edited Thursday, May 03, 2012 5:19 AM
PRND321 Till I DIE
Old Motor: 160whp & 152ft/lbs, 1/4 Mile 15.4 @88.2
M45 + LD9 + 4T40-E, GO GO GO
-MD- Enforcer wrote:
Ryan your thoughts?
You pretty much summed it up Mike!
P&P Tuning
420.5whp / 359.8wtq
Use this calculator for help!
For calc...
205/50/16 is stock tire size.
Final Drive: 3.91
First: 2.96
Second: 1.63
Third: 1.00
Fourth: 0.68
Stock Redline RPM 6550.
Edited 1 time(s). Last edited Thursday, May 17, 2012 9:57 AM
PRND321 Till I DIE
Old Motor: 160whp & 152ft/lbs, 1/4 Mile 15.4 @88.2
M45 + LD9 + 4T40-E, GO GO GO
Nice work. Thanks Mike.
So with the TCS/VSS settings all maxed out, it still does the bouncing off the rev limiter thing between shifts. Shiftplus is off as well. Things would be great if I could get past that. You feel the power surge and pull nice and hard as soon as it stops doing that. So the best time I've gotten was a 13.05 at about 15-16psi. You can deff tell thats slowing me down though since it pulls so hard as soon as it stops doing that.
The new throttle seems to be working pretty good. Only issue is an occasion CEL of "idle RPM higher than expected". I'll try swapping out the IAC later. Thanks again for your help with the adapter.
12.6 @ 114.6 MPH
Welcome...also this is what I just posted on facebook....
Riddle me this. So a stock 99 cavalier transmission tune it setup to shift at 35MPH and 6350RPM. The only problem is according to the gear ratios at 35mph it would shift at 5850rpm, or at 6350rpm should be at 39MPH.
Second is 65mph @ 6400RPM. Gear ratios would say at 65MPH you would be at 5800rpm, or at 6400RPM should be at 72mph.
Third is 100mph @ 5800RPM. Gear ratios would say at 100mph you would be at 5500rpm, or at 5800rpm should be at 106rpm.
So looking back at my dyno graphs it hit my speed limiter of 106mph in third at almost exactly 5800rpm.
So looking at other GM tunes for automatics it seems that GM likes to program the computer to see the MPH first, and then hit the RPM limit. This is the same as the Z24 as well.
So in theory if one was to raise the MPH of first to say 38MPH and the RPM to 6900rpm. It should shift the same.
So at 38MPH you really would be at 6200RPM, or at 6900rpm be at 42.5MPH. That is a fairly large jump. Maybe it would be safer to go the other way. lol Who want to play lets see if the trans shifts at 6900RPM...
So I should try....So set first for 36.5MPH and 6500RPM. That is a little safer of a test! At 36.5 rpm per gear ratio would be 5925rpm, or at 6500rpm be at 40mph.
PRND321 Till I DIE
Old Motor: 160whp & 152ft/lbs, 1/4 Mile 15.4 @88.2
M45 + LD9 + 4T40-E, GO GO GO
I believe it does go by speed rather than RPM. I've been comparing my logs to settings and damn near every time, it initiated the shift exactly at the speed it was set to regardless of what RPM the engine was at. Before I noticed this, I raised all my speeds based off of that calculator (changed specs to 4T40E first), then I started the log comparison and realized what you just did as well. I lowered all speeds just a hair based on logs as to what RPM I'd most likely be at from previous runs. I won't be able to get to the track for another 2 weeks, so we'll see. I'll keep you updated.
12.6 @ 114.6 MPH
Sounds good. Maybe I can join you with my cav.
PRND321 Till I DIE
Old Motor: 160whp & 152ft/lbs, 1/4 Mile 15.4 @88.2
M45 + LD9 + 4T40-E, GO GO GO
Well wish me luck...All is changed...going for drive in a sec...
PRND321 Till I DIE
Old Motor: 160whp & 152ft/lbs, 1/4 Mile 15.4 @88.2
M45 + LD9 + 4T40-E, GO GO GO
