Go in the transmission tune and disable torque management for downshift.. that will get rid of the rev matching.
Go in the transmission tune and disable torque management for downshift.. that will get rid of the rev matching.
"All that is needed for the triumph of evil is that good men do nothing..."
28min idle is wayyyyy high, try around 10 and go up or down +-3/4 , it should want something around there.
Also note, you will need to let the car idle for a bit after flashing with slight revs and such to work with the idle relearn.
From my experience, no matter what changes, the the first engine start will idle terribly due to the relearn.
B1651/1652 are hard limits on throttle percentage. It doesn't matter how high a number you put in B1829, it won't go above 1651/1652 and will not be able to run when cold. That's the flaw in the drill a hole method. If you don't want to drill a hole (I won't drill one) the method won't work.
I did try this before with no luck. It does not appear to the be the same as rev matching. My stock 06 tune does not have rev matching becasue its an 06 and it does the jerky downshift thing with that tune as well. The modified tune for my modified transmission is from an 08 with rev matching and it also has the same jerky downshift problem.Originally Posted by Highlander
On another note when in sport mode the rev matching does work but the 3-2 shift and the 2-1 shift it rev matches and then shifts after the rev so no benefit. In other words the shift is to slow to take advantage of the rev match. So I need to delay the rev match or speed up the shift. I have been unable to figure out either one.
It is possible that I did not try long enough but I did try it a few times. I am quite confident that I hit the maximum setting on min idle airflow B1829 long before I got to 28 g/sec and it was just reading from the max idle B1652 number of 1.41. But what is weird is that with the corrections at 50% of stock it still would not idle maybe I just need to keep trying until it learns. Also This is not a speed density tune I am using the MAF which after reading here some more might be the problem?
I agree with you. I think I hit the max probably at around 14 or 15 g/sec in B1829 and it was using B1652 max idle area instead. But what I don't get is why it would not idle with just the correction turned on and B1829 maxed out? The step size tables B1844/5 are 50% of stock as recomended. Seems like from everything I read here it should be idling even if B1829 hit its max. Is there a chance that at 28 g/sec it was not maxed out and I need to go further? Maybe I just did not give it time to learn? How much time do I need to give it? Why won't the method work without the hole, what I read in hymey's posts was that it can only allow a 4% adjustment which he went on to say later was not a problem in big cube engines with small throttle bodies. Can I achieve the desired results adjusting B1650 max ETC area as suggested by some here? At some point I am going to upgrade to a 102mm throttle body and MAF and would like to avoid drilling my stock one if I can. After all the car idles fine I am just trying to eliminate this other downshifting issue.
Wait a minute. I thought we all agreed that you had to add to the base of 490-220 the difference from the stock cam to the new cam. I.E. My cam at .050" opens 28* earlier than the stock cam. Therefor I add 28* to the stock table that trims from 490-220. I now get 518-248. Where are you getting the solid number from and why are we subtracting now? Wouldn't that put injector timing too late after the valve opens if we subtract from the stock table since it is set up to End Of Injector Timing before the Intake valve opens stock? When I add the cam timing difference I have to pull a ton of fuel at idle. This to me says that I am not wasting fuel any more down an open intake valve. I understand your math but it is a little hard based off of advertised. I will have to go look at my cam card again. Are you not compensating for ECT and IVT any more either with one solid number? What am I missing?237 242 is a texas speed cam ? Thats 286 deg advertised duration. Half that is 143 degrees. Take that from 110 intake centreline. The inlet opens at minus 33 degrees btdc overlap . Add 360 to get it back to tdc fire so thats 393 degrees btdc compression for ending the injection. Then add another ten degrees on so it hits the back of the valve and atomizes before the valve opens. Thats 393 plus 10. 403 degrees is optimal. So 400 is close enough. Yes vve will be out a bit. Will drive like a stocker with no surging in open loop with fueling timing and most importantly airflow tables correct.
02 Z06, 573/530rw N/A 416, 10.21@136.12.
The biggest issue I had on my most recent tuning job involving a cammed 2012 Camaro was Idle with AC on and Idle speed dropping to much after a free rev.
After playing with B5157 I was able to reduce the idle hunting , Timing drop during AC kicking on , and idle dropping down during throttle blip.
I might do just this...I'm very tired of fighting the idle in my car with this flywheel...makes me never want to drive it.The biggest issue I had on my most recent tuning job involving a cammed 2012 Camaro was Idle with AC on and Idle speed dropping to much after a free rev.
After playing with B5157 I was able to reduce the idle hunting , Timing drop during AC kicking on , and idle dropping down during throttle blip.
Wow, what a great read!
Sounds like E38 Idle Tuning has come a long way through the years. Posting here in case the problem I experience may help other (assuming a solution of course!).
One simple question - Are you selecting "Idle Relearn Reset" after each new tune that is flashed?
Now the problem - I have almost 12 grams of idle air, and much more cranking. Car fires right up, but then starts sputtering and dies out. Give it a little gas and the idle will settle and it will not stall again. The issue mostly happens on hot starts, and when starting to move. Seems like timing and TP are not moving erratic, so not sure what it could be. It doesn't seem like a max idle hard limit, because it is going to almost 23.7% TP on decel and key on engine off. I went for a 20 minute ride after getting it to stay running, and did not have any stalling issues, ran fine through a parking lot with minimal surging. The idle seems a bit high as I'm commanding 900 and getting 950-975, but I would think that mush air would be causing a much higher idle with more timing correction. I did 0 out 0-48 RPM corrections (low, high, park, in gear) to avid erratic timing, so that is part of it.
Specs on combo:
LS2 with MS4 Cam 239/242, .649"/.600", 110 LSA
Long tube headers
Bosch Green Top injectors (42#)
FAST 92 MM manifold
Ls3 Throttle Body
5 speed Tremec
Last edited by LastCall; October 16th, 2016 at 06:31 PM.
00 Silverado Z71, LQ9 w/ LS3 heads, BTR cam, Whipple 2.9@8#, 4l80E
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