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727 Gains RPM Issue #3055723 07/04/22 09:00 AM 07/04/22 09:00 AM
Joined: Jan 2003 Posts: 3,830 N.E. Ohio 6bblFLASH OP master
6bblFLASH OP master Joined: Jan 2003 Posts: 3,830 N.E. Ohio	Trying to help out a friend. NSS/MW car,10.70s 4.10gear. 493in wedge Last year it would occasionally gain RPM about the 1,000ft mark. Jump from 6,200 to nearly 7,000...car would slow 5 to 8 hundredths. Had trans gone thru by a GOOD trans guy and fellow MW racer. Only thing he found was some slippage on 3rd clutch. Refreshed and back in. Got worse. Ordered a new converter 9.5". Car picked up 60ft....but now gains RPM even more frequently. Pulled the trans again...teardown...no damage or evidence whatsoever. Is totally unpredictable, but he says it seems more frequent as it gains temperature...so installed bigger cooler and a gauge. Never gets past 170. I thought it sounded like it is not keeping the converter full..IE. emptying the pan. Been through all the usual things..fuel pressure/volume ..ignition...shifter. Ideas??? 70` Cuda`,440 6BBL Jerico,Dana 4.56 Still on 93 Pump Gas 9.87 @ 136/1.31-60ft.`09 Mopar Nationals PASSON PERFORMANCE "Stick-Shift" Champ! 2013 StickShift Challenge Winner@ Mopar Nationals!

Re: 727 Gains RPM Issue [Re: 6bblFLASH] #3055728 07/04/22 09:21 AM 07/04/22 09:21 AM
Joined: Feb 2008 Posts: 714 Central TEXAS!!!! sr4440 super stock
sr4440 super stock Joined: Feb 2008 Posts: 714 Central TEXAS!!!!	What transmission fluid is he using? Joe Without Data, you’re just another guy with an opinion.

Re: 727 Gains RPM Issue [Re: sr4440] #3055737 07/04/22 10:41 AM 07/04/22 10:41 AM
Joined: Jan 2003 Posts: 3,830 N.E. Ohio 6bblFLASH OP master
6bblFLASH OP master Joined: Jan 2003 Posts: 3,830 N.E. Ohio	Not sure. Probably Type F 70` Cuda`,440 6BBL Jerico,Dana 4.56 Still on 93 Pump Gas 9.87 @ 136/1.31-60ft.`09 Mopar Nationals PASSON PERFORMANCE "Stick-Shift" Champ! 2013 StickShift Challenge Winner@ Mopar Nationals!

Re: 727 Gains RPM Issue [Re: 6bblFLASH] #3055742 07/04/22 10:58 AM 07/04/22 10:58 AM
Joined: May 2003 Posts: 13,185 aZLiViN J J_BODY I Live Here
J_BODY I Live Here J Joined: May 2003 Posts: 13,185 aZLiViN	Is this per data recording?

Re: 727 Gains RPM Issue [Re: J_BODY] #3055747 07/04/22 11:06 AM 07/04/22 11:06 AM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	If you have had the trans looked at a couple of times with nothing wrong, start looking elsewhere

Re: 727 Gains RPM Issue [Re: J_BODY] #3055748 07/04/22 11:13 AM 07/04/22 11:13 AM
Joined: Jan 2003 Posts: 3,830 N.E. Ohio 6bblFLASH OP master
6bblFLASH OP master Joined: Jan 2003 Posts: 3,830 N.E. Ohio	Originally Posted by J_BODY Is this per data recording? No...tach goes up ...car noses over. 70` Cuda`,440 6BBL Jerico,Dana 4.56 Still on 93 Pump Gas 9.87 @ 136/1.31-60ft.`09 Mopar Nationals PASSON PERFORMANCE "Stick-Shift" Champ! 2013 StickShift Challenge Winner@ Mopar Nationals!

Re: 727 Gains RPM Issue [Re: sr4440] #3055749 07/04/22 11:14 AM 07/04/22 11:14 AM
Joined: Jan 2003 Posts: 3,830 N.E. Ohio 6bblFLASH OP master
6bblFLASH OP master Joined: Jan 2003 Posts: 3,830 N.E. Ohio	Originally Posted by sr4440 What transmission fluid is he using? Joe Type F from NAPA 70` Cuda`,440 6BBL Jerico,Dana 4.56 Still on 93 Pump Gas 9.87 @ 136/1.31-60ft.`09 Mopar Nationals PASSON PERFORMANCE "Stick-Shift" Champ! 2013 StickShift Challenge Winner@ Mopar Nationals!

Re: 727 Gains RPM Issue [Re: MR_P_BODY] #3055750 07/04/22 11:17 AM 07/04/22 11:17 AM
Joined: Jan 2003 Posts: 3,830 N.E. Ohio 6bblFLASH OP master
6bblFLASH OP master Joined: Jan 2003 Posts: 3,830 N.E. Ohio	Originally Posted by MR_P_BODY If you have had the trans looked at a couple of times with nothing wrong, start looking elsewhere Agreed...but what else will gain RPM and lose acceleration together? 70` Cuda`,440 6BBL Jerico,Dana 4.56 Still on 93 Pump Gas 9.87 @ 136/1.31-60ft.`09 Mopar Nationals PASSON PERFORMANCE "Stick-Shift" Champ! 2013 StickShift Challenge Winner@ Mopar Nationals!

Re: 727 Gains RPM Issue [Re: 6bblFLASH] #3055754 07/04/22 11:23 AM 07/04/22 11:23 AM
Joined: Oct 2010 Posts: 2,404 Ambridge, Pa. R rickraw top fuel
rickraw top fuel R Joined: Oct 2010 Posts: 2,404 Ambridge, Pa.	Check your line pressure in high gear. Might be some pressure loss?

Re: 727 Gains RPM Issue [Re: 6bblFLASH] #3055756 07/04/22 11:36 AM 07/04/22 11:36 AM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	Does this car have RPM limiters of any nature.. if so try to borrow some others... or get new ones (not sure if NSS cars use them)

Re: 727 Gains RPM Issue [Re: 6bblFLASH] #3055817 07/04/22 12:29 PM 07/04/22 12:29 PM
Joined: Jan 2003 Posts: 25,729 Rio Linda, CA John_Kunkel Too Many Posts
John_Kunkel Too Many Posts Joined: Jan 2003 Posts: 25,729 Rio Linda, CA	I'm thinking the transmission guy is missing something awry in one of the clutches or the pump. Deep pan or shallow? If the VB allows a line pressure gauge tap, a gauge plumbed into the cockpit might show a pressure drop at top end. If the center tap on the case is blocked, a gauge at the front servo will work. The INTERNET, the MISinformation superhighway

Re: 727 Gains RPM Issue [Re: MR_P_BODY] #3055825 07/04/22 12:43 PM 07/04/22 12:43 PM
Joined: Jan 2003 Posts: 3,830 N.E. Ohio 6bblFLASH OP master
6bblFLASH OP master Joined: Jan 2003 Posts: 3,830 N.E. Ohio	Originally Posted by MR_P_BODY Does this car have RPM limiters of any nature.. if so try to borrow some others... or get new ones (not sure if NSS cars use them) I'm sure it has a MSD chip for max RPM. I will find out. 70` Cuda`,440 6BBL Jerico,Dana 4.56 Still on 93 Pump Gas 9.87 @ 136/1.31-60ft.`09 Mopar Nationals PASSON PERFORMANCE "Stick-Shift" Champ! 2013 StickShift Challenge Winner@ Mopar Nationals!

Re: 727 Gains RPM Issue [Re: 6bblFLASH] #3055828 07/04/22 12:44 PM 07/04/22 12:44 PM
Joined: Jan 2003 Posts: 3,830 N.E. Ohio 6bblFLASH OP master
6bblFLASH OP master Joined: Jan 2003 Posts: 3,830 N.E. Ohio	He is going to install another transmission and see what happens. So we'll see what happens. I'll update when he gets results Thanks everyone.... 70` Cuda`,440 6BBL Jerico,Dana 4.56 Still on 93 Pump Gas 9.87 @ 136/1.31-60ft.`09 Mopar Nationals PASSON PERFORMANCE "Stick-Shift" Champ! 2013 StickShift Challenge Winner@ Mopar Nationals!

Re: 727 Gains RPM Issue [Re: 6bblFLASH] #3055984 07/04/22 09:47 PM 07/04/22 09:47 PM
Joined: Mar 2011 Posts: 3,068 Michigan A A727Tflite master
A727Tflite master A Joined: Mar 2011 Posts: 3,068 Michigan	Originally Posted by 6bblFLASH Trying to help out a friend. NSS/MW car,10.70s 4.10gear. 493in wedge Last year it would occasionally gain RPM about the 1,000ft mark. Jump from 6,200 to nearly 7,000...car would slow 5 to 8 hundredths. Had trans gone thru by a GOOD trans guy and fellow MW racer. Only thing he found was some slippage on 3rd clutch. Refreshed and back in. Got worse. Ordered a new converter 9.5". Car picked up 60ft....but now gains RPM even more frequently. Pulled the trans again...teardown...no damage or evidence whatsoever. Is totally unpredictable, but he says it seems more frequent as it gains temperature...so installed bigger cooler and a gauge. Never gets past 170. I thought it sounded like it is not keeping the converter full..IE. emptying the pan. Been through all the usual things..fuel pressure/volume ..ignition...shifter. Ideas??? What do you mean he saw slippage on 3rd gear clutch? What did he see exactly. Any issues with change in the stall speed or 60’? If you have a spare valve body I would try that first.

Re: 727 Gains RPM Issue [Re: A727Tflite] #3056091 07/05/22 09:36 AM 07/05/22 09:36 AM
Joined: Jan 2003 Posts: 2,296 NE Ohio DoubleD top fuel
DoubleD top fuel Joined: Jan 2003 Posts: 2,296 NE Ohio	take a look at the lines to the trans cooler - are they a soft braided or a rubber line - you might be sucking one closed - also look at the cooler itself junk inside can act like a valve restricting flow Also could be the valve body acting up - or the shifter is not aligned perfectly

Re: 727 Gains RPM Issue [Re: DoubleD] #3056107 07/05/22 09:46 AM 07/05/22 09:46 AM
Joined: Mar 2011 Posts: 3,068 Michigan A A727Tflite master
A727Tflite master A Joined: Mar 2011 Posts: 3,068 Michigan	Originally Posted by DoubleD take a look at the lines to the trans cooler - are they a soft braided or a rubber line - you might be sucking one closed - also look at the cooler itself junk inside can act like a valve restricting flow Also could be the valve body acting up - or the shifter is not aligned perfectly Both cooler lines are under pressure at all times when not in park.

Re: 727 Gains RPM Issue [Re: A727Tflite] #3056125 07/05/22 09:54 AM 07/05/22 09:54 AM
Joined: Jan 2003 Posts: 2,296 NE Ohio DoubleD top fuel
DoubleD top fuel Joined: Jan 2003 Posts: 2,296 NE Ohio	Originally Posted by Transman Originally Posted by DoubleD take a look at the lines to the trans cooler - are they a soft braided or a rubber line - you might be sucking one closed - also look at the cooler itself junk inside can act like a valve restricting flow Also could be the valve body acting up - or the shifter is not aligned perfectly Both cooler lines are under pressure at all times when not in park. I don't disagree - but pressure and flow are two different things in a hydraulic system

Re: 727 Gains RPM Issue [Re: 6bblFLASH] #3056138 07/05/22 10:07 AM 07/05/22 10:07 AM
Joined: May 2008 Posts: 5,399 Aurora, Colorado 451Mopar master
451Mopar master Joined: May 2008 Posts: 5,399 Aurora, Colorado	Could be either clutch pack(s) or converter? If the clutch pack is slipping, you should see the increased wear of the clutches and heat in the steels. Some info in rear clutch pistons and bellview springs: https://www.youtube.com/watch?v=V9Zl4gay5Jo&t=39s Last edited by 451Mopar; 07/05/22 10:08 AM.

Re: 727 Gains RPM Issue [Re: 6bblFLASH] #3056502 07/06/22 12:57 AM 07/06/22 12:57 AM
Joined: Jan 2003 Posts: 1,990 s. e. pa. C calrobb2000 top fuel
calrobb2000 top fuel C Joined: Jan 2003 Posts: 1,990 s. e. pa.	wrong seals in clutch pack ?

Re: 727 Gains RPM Issue [Re: A727Tflite] #3056513 07/06/22 02:36 AM 07/06/22 02:36 AM
Joined: Aug 2003 Posts: 43,097 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,097 Bend,OR USA	Originally Posted by Transman [quote=DoubleD Both cooler lines are under pressure at all times when not in park. isn't it around 30 lbs. or less pressure(maybe 15 to 20 Lbs. ) to the tranny cooler Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

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