4l60e nitrous issue
#1
4l60e nitrous issue
i dynoed 505 on a 150 shot, .. i have stock 4l60e and stock stall on a 98 pcm.
I'm dead set on a 4l80 after talking to jakes transmissions, but just out of curiosity:
I did a test shot with a 1/4 full nitrous bottle and my trans bangs rev 1-2 and 2-3. My WOT on n/a works fine from a stand still stalled at 1600, but from a 35'ish roll it'll bang rev when i have it in 1 (not all the time.. but the same with n20). If i let off the gas and floor it again it will shift.
Now my theory is, its my shift points or my pcm is too slow. OR ..is my tranny finally giving out? 55k miles
thanks
I'm dead set on a 4l80 after talking to jakes transmissions, but just out of curiosity:
I did a test shot with a 1/4 full nitrous bottle and my trans bangs rev 1-2 and 2-3. My WOT on n/a works fine from a stand still stalled at 1600, but from a 35'ish roll it'll bang rev when i have it in 1 (not all the time.. but the same with n20). If i let off the gas and floor it again it will shift.
Now my theory is, its my shift points or my pcm is too slow. OR ..is my tranny finally giving out? 55k miles
thanks
#2
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Well even though you're pushing the limits of a stock 4l60e, you car shifts fine n/a so that's good. What are your desired shift points and where are you cutting off the nitrous at, or are you trying to spray through the shifts? Have your tuner log some passes. He might need to lower your shift mph and/or RPM a little and see if it'll shift on the bottle. Both values need to be satisfied to command a shift. Also, every car is different and hardly will it ever shift exactly what it's set at in your computer. There's always going to be a delay, some more than others so if you don't lower it to command a sooner shift you'll hit the rev limiter. Especially on the bottle, or did it shift fine on the bottle at one time and now all of a sudden it started to hit the rev limiter?
#3
Well even though you're pushing the limits of a stock 4l60e, you car shifts fine n/a so that's good. What are your desired shift points and where are you cutting off the nitrous at, or are you trying to spray through the shifts? Have your tuner log some passes. He might need to lower your shift mph and/or RPM a little and see if it'll shift on the bottle. Both values need to be satisfied to command a shift. Also, every car is different and hardly will it ever shift exactly what it's set at in your computer. There's always going to be a delay, some more than others so if you don't lower it to command a sooner shift you'll hit the rev limiter. Especially on the bottle, or did it shift fine on the bottle at one time and now all of a sudden it started to hit the rev limiter?
I changed the trans fluid and the filter 20k miles ago, and at first i thought the trans fluid might be the culprit since its a lil more 'slippery' and requires a break in period +/- from what i understood. (dex 3 oreilys brand) when i first sprayed my car i had 20k~ miles and it did shift with a slight hang under 7k but it would shift. I didnt trying spraying from a stand still again recently, i tried spraying form a 35 roll only and i shifted on the shifter from 1-D and it just bangs (low bottle pressure too from lack of n2o in the bottle) It didn't start to bang rev till i changed the fluid, if that means anything.
I have a window switch from 3-6.5 i think, with no progression, I'll have to ask my tuner what he set it at exactly but its definitely in the 6k range.
I have a nano, but its not hooked up, I'm looking to put it on soon.
I need to log some passes
#4
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The stock tune has the WOT shift mph and rpm very close to redline. Your nitrous is probably causing the torque converter to slip a bit more and you are therefore hitting the rev limiter just before hitting the shift MPH.
As rmata said, have the tuner reduce the WOT shift MPH by e.g. 5 mph, and you should be good to go.
As rmata said, have the tuner reduce the WOT shift MPH by e.g. 5 mph, and you should be good to go.
#6
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The stock tune has the WOT shift mph and rpm very close to redline. Your nitrous is probably causing the torque converter to slip a bit more and you are therefore hitting the rev limiter just before hitting the shift MPH.
As rmata said, have the tuner reduce the WOT shift MPH by e.g. 5 mph, and you should be good to go.
As rmata said, have the tuner reduce the WOT shift MPH by e.g. 5 mph, and you should be good to go.
Had the same problem with my car. Had the window switch set to 5600 and car shifted perfect..then tried to up it to 5800 and just banged the rev limiter. I turned it back down to 5600 and never had a problem out of it again.
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#8
if i may ask, how many times did u spray on your 4l60?
Oh that is being put on my budget as we speak, going with a level 2 4l80 w/ revmax converter. I'm not even going to keep ******* with a 4l60, I'm tired of it.