Atap results: line pressure at shift
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From: Victoria, TX
Re: Atap results: line pressure at shift How do you get such high psi (140-160) from .53A when it's sort of between the 55psi and 165-180 number? From what I've heard, GM sets the 2-3 shift at 75% of the psi of the 1-2 shift. That would put the 2-3 shift closer to 125 psi if I'm not mistaken.
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2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
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From: Live Oak, FL - in the woods where the creatures lurk.
Re: Atap results: line pressure at shift Well, that's a good question. Someone posted a link to a chart, I copied the chart. Is it right? Dunno. I'll look for the link.
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Re: Atap results: line pressure at shift Okay, here's the link someone posted:
http://www.transonline.com/electroPu...cfm?pageID=564
http://www.transonline.com/electroPu...cfm?pageID=564
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Re: Atap results: line pressure at shift Okay, the first post was with the tranny temps fairly low (110-130).
After another run with I suspect (but did not monitor) the tranny temps were a little higher:
1-2 shift 0.33A, 100% calc load
2-3 shift 0.45A, 98.43 calc load
Seems there could also be a correlation between trans oil temp and pressure, (makes sense) but the commanded pressure, i.e. Amp readings are higher. Might take a lot of logging to average out some numbers.
After another run with I suspect (but did not monitor) the tranny temps were a little higher:
1-2 shift 0.33A, 100% calc load
2-3 shift 0.45A, 98.43 calc load
Seems there could also be a correlation between trans oil temp and pressure, (makes sense) but the commanded pressure, i.e. Amp readings are higher. Might take a lot of logging to average out some numbers.
Re: Atap results: line pressure at shift Glad to see you found that parameter on Atap.Your results are slightly better on the 1-2 shift & about in line on the 2-3 shift with the 3 cars I tested.Either way,this further proves that our tranny's do not shift at full pressure as is commonly said.
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From: Live Oak, FL - in the woods where the creatures lurk.
Atap results: line pressure at shift Made a couple of runs logging "Press Cont Act Crrnt", rpm, current gear.
1-2 shift (both runs): 0.16A (165-185 psi?)
2-3 shift (both runs): 0.53A (140-160 psi?)
Cruising @ 1450 rpm: 1.05A (<55 psi?)
Forgot to catch calculated load these runs.
Comments on how that compares with you?
I have 100% stock MAF, Direct Flo Lid, "home ported" TB, Yank ST3500.
1-2 shift (both runs): 0.16A (165-185 psi?)
2-3 shift (both runs): 0.53A (140-160 psi?)
Cruising @ 1450 rpm: 1.05A (<55 psi?)
Forgot to catch calculated load these runs.
Comments on how that compares with you?
I have 100% stock MAF, Direct Flo Lid, "home ported" TB, Yank ST3500.
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From: Live Oak, FL - in the woods where the creatures lurk.
Re: Atap results: line pressure at shift I would be interested in seeing any before/after numbers with a change from stock to ported MAF, if any available.
If the variables the pcm looks at are:
calculated load
MAP
TPS
Trans oil temp (maybe?)
ECT
Is calculated load taken solely from the MAF, or is it a combination of factors?
If the variables the pcm looks at are:
calculated load
MAP
TPS
Trans oil temp (maybe?)
ECT
Is calculated load taken solely from the MAF, or is it a combination of factors?
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Re: Atap results: line pressure at shift Yes, my MAF assy is stock, screen in, and ported (I think, I'll have to check <img src="gr_emb.gif" border="0"> ). My Throttle body, OTOH, has been modified, but I don't think that would have any bearing here, or would it?
I'll do some more runs with fewer parameters, check my MAF, and then I think I'll try some with the setup I had in there before (stock ported MAF w/red Granatelli ends) just for shnitz & grins.
If anybody knows a way to post up .xls files here, let me know. (Don't have a website)
Rich
Notice: All this is on hold 'til the weather clears up. We're supposed to get snow and rain here in Dallas all weekend, so I'm staying home and doing some <img src="graemlins/gr_chug.gif" border="0" alt="[chug]" />
<img src="gr_grin.gif" border="0">
[ March 01, 2002: Message edited by: Rich3fan ]</p>
I'll do some more runs with fewer parameters, check my MAF, and then I think I'll try some with the setup I had in there before (stock ported MAF w/red Granatelli ends) just for shnitz & grins.
If anybody knows a way to post up .xls files here, let me know. (Don't have a website)
Rich
Notice: All this is on hold 'til the weather clears up. We're supposed to get snow and rain here in Dallas all weekend, so I'm staying home and doing some <img src="graemlins/gr_chug.gif" border="0" alt="[chug]" />
<img src="gr_grin.gif" border="0">
[ March 01, 2002: Message edited by: Rich3fan ]</p>
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From: Live Oak, FL - in the woods where the creatures lurk.
Re: Atap results: line pressure at shift Cool. When you get some data, if you can't get it posted up, will you email to me? Excel format is fine; I can't post it but I can look at it.
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From: Holly Springs NC
Re: Atap results: line pressure at shift Hi Daryl<--probably spelled it wrong what else is new? <img src="images/icons/rolleyes.gif" border="0"> And Hello Rich, long time it's been.
Claire <img src="gr_images/icons/wink.gif" border="0">
Claire <img src="gr_images/icons/wink.gif" border="0">
On The Tree
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Re: Atap results: line pressure at shift Hi Claire, yes it has...
I got good news, and I got bad news. The good news is, I got one WOT run in under pretty good conditions. The bad news is...
I got caught in the act! <img src="gr_images/icons/mad.gif" border="0">
It's my own damn fault though. I told him what I was doing, but he didn't care. 22 mph over the limit. It's been exactly 1 year since I last took Defensive Driving, so you know where I'm heading. <img src="graemlins/gr_devil.gif" border="0" alt="[devil]" />
Anyway, the .xls file is on it's way gwj. If anyone else wants a look-see, LMK.
Rich
[ March 08, 2002: Message edited by: Rich3fan ]</p>
I got good news, and I got bad news. The good news is, I got one WOT run in under pretty good conditions. The bad news is...
I got caught in the act! <img src="gr_images/icons/mad.gif" border="0">
It's my own damn fault though. I told him what I was doing, but he didn't care. 22 mph over the limit. It's been exactly 1 year since I last took Defensive Driving, so you know where I'm heading. <img src="graemlins/gr_devil.gif" border="0" alt="[devil]" />
Anyway, the .xls file is on it's way gwj. If anyone else wants a look-see, LMK.
Rich
[ March 08, 2002: Message edited by: Rich3fan ]</p>
Re: Atap results: line pressure at shift Hi Claire,Yes you spelled it wrong AGAIN. <img src="images/icons/rolleyes.gif" border="0">
Rich ,Sorry to hear about your ticket.
With all the Atap runs I've been making lately,I thought for sure it would be me getting that ticket.
I had an interesting conversation with an engineer from TransGo.He said that those amperage #'s we're monitoring are not an exact measurement of what the line pressure is actually doing.He said there is enough discrepency between different solenoids that .1 amp on one could equal the same line pressure as .3 for someone else!The only way to know for sure is to put a pressure gauge on it.He also said NOT to use thier kit on 98 & up cars until Torque Management has been removed.He said the kit can actually worsen or create TM problems where you didn't have them before.
Rich ,Sorry to hear about your ticket.
With all the Atap runs I've been making lately,I thought for sure it would be me getting that ticket.
I had an interesting conversation with an engineer from TransGo.He said that those amperage #'s we're monitoring are not an exact measurement of what the line pressure is actually doing.He said there is enough discrepency between different solenoids that .1 amp on one could equal the same line pressure as .3 for someone else!The only way to know for sure is to put a pressure gauge on it.He also said NOT to use thier kit on 98 & up cars until Torque Management has been removed.He said the kit can actually worsen or create TM problems where you didn't have them before.
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From: Live Oak, FL - in the woods where the creatures lurk.
Re: Atap results: line pressure at shift Got it, Rich. Sorry about the ticket. <img src="gr_sad.gif" border="0">
AFTICA; Yes, I agree different solenoids will differ in current draw.
I'm not sure what to say about results, not enough data yet. I'll try to get some more runs this week (back roads!)
AFTICA; Yes, I agree different solenoids will differ in current draw.
I'm not sure what to say about results, not enough data yet. I'll try to get some more runs this week (back roads!)
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From: Live Oak, FL - in the woods where the creatures lurk.
Re: Atap results: line pressure at shift Anyone else out there want to send some data including solenoid current, ported MAF/stock MAF/Pace MAF,Granatelli MAF etc., I will try to get a database together and see if there are any constants.