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Re: Big power & 727… input or output shaft the weak link? [Re: polyspheric] #3125707 03/01/23 05:00 PM 03/01/23 05:00 PM
Joined: Jan 2003 Posts: 75,005 U.S.S.A. JohnRR I Win
JohnRR I Win Joined: Jan 2003 Posts: 75,005 U.S.S.A.	Originally Posted by polyspheric What does this remind me of? "When should I stop "improving" my 8-3/4 and get a 9"?" Rossler T400 They blow up too. running up my post count some more .

Re: Big power & 727… input or output shaft the weak link? [Re: topfueldart] #3125708 03/01/23 05:03 PM 03/01/23 05:03 PM
Joined: Jan 2003 Posts: 75,005 U.S.S.A. JohnRR I Win
JohnRR I Win Joined: Jan 2003 Posts: 75,005 U.S.S.A.	Originally Posted by topfueldart Originally Posted by J_BODY I’d run em! Personally I’ll think you’ll be fine. At its current power level, I think it’s ok, but being it’s turbo’d, it’s really easy to pickup another 100 horse. I did already break a set of stock pump gears, and I plan to do a drag and drive this year, so considering all upgrade options since it’s already out. I think my combo is potentially pretty hard on hard parts leaving on a bunch of boost with the transbrake, and stiff/short radials. Spend it now or spend it later. Trans is out, it's hard to find 727 parts when everyone else is running .. insert GM trans here .... running up my post count some more .

Re: Big power & 727… input or output shaft the weak link? [Re: JohnRR] #3125718 03/01/23 05:45 PM 03/01/23 05:45 PM
Joined: Jan 2003 Posts: 2,697 Renton Wa T topfueldart OP master
topfueldart OP master T Joined: Jan 2003 Posts: 2,697 Renton Wa	Originally Posted by JohnRR A friend of mine was doing the burnout contest at carlisle one year and broke the output shaft at the end of the front planet splines. Car was stationary , 383 - 2bbl in a 69 Satellite wagon. What happened was the spiders in his single track 3.23 gear rear end seized on it's shaft shaft and in the split second it took for the spiders to break into pieces it shocked the driveline enough to break the output shaft. He was lucky because the rear sprag in the trans was also rolled, I don't know when that happened though as he didn't really beat on the car outside of that one burnout contest. My pumps gears broke on decel or engine shut off, after a usual pass. Fired the car back up at the ticket shack and it wouldn’t move. 11.48 @ 120 with a 1.80 60' 318, stock 1.88 heads, stock 904, Pump Gas, 13 lbs of boost. 9.94 @ 134, 318 on pump gas, 14 lbs w/ Eddies, transbrake 727, 3600 lbs, 3.54 gear and 28's.

Re: Big power & 727… input or output shaft the weak link? [Re: 440Jim] #3125753 03/01/23 07:38 PM 03/01/23 07:38 PM
Joined: Jan 2003 Posts: 11,711 Portage,michigan B B3422W5 I Live Here
B3422W5 I Live Here B Joined: Jan 2003 Posts: 11,711 Portage,michigan	Originally Posted by 440Jim Originally Posted by dvw My input and output shafts have 850+ passes. Though all are footbrake. I've broken 3 Dana pinion gears. Dizusters turbo car also ran stock shafts. Its broken rear axle pinion shafts, aftermarket steel drive shafts. But never either trans shaft, Both were over 850 hp. His weighed 3750, mine 3350. Both are 65 push button. Both have stripped stock front planet carriers. Both run stock pump gears. Doug I broke the "ears" off one set of stock 727 pump gears also. It happened during the Mopar weekend about 2008, during time trials. With the help of a couple racers, we pulled the trans, took it apart, found some new pump gears at a vendor; and I made the first round of eliminations. I remember being under your Dart getting it out….lol You helped me running a charger up to the lanes in later rounds 69 Dart GTS A4 Silver All steel, flat factory hood, 3360race weight 418 BPE factory replacement headed stroker, 565 lift solid cam Best so far, 10.40 @127 1/4 1.41 best 60 foot 6.60 at 103.90 1/8

Re: Big power & 727… input or output shaft the weak link? [Re: topfueldart] #3125825 03/02/23 12:25 AM 03/02/23 12:25 AM
Joined: Jan 2007 Posts: 287 So. IL. USA PLUM BAD enthusiast
PLUM BAD enthusiast Joined: Jan 2007 Posts: 287 So. IL. USA	I broke a hub two years ago. [/url][/img] And a band anchor last year. [/url][/img]

Re: Big power & 727… input or output shaft the weak link? [Re: polyspheric] #3125841 03/02/23 08:17 AM 03/02/23 08:17 AM
Joined: Jan 2022 Posts: 138 Connellsville 7 71Demon528 member
71Demon528 member 7 Joined: Jan 2022 Posts: 138 Connellsville	T400s fail too, just like every transmission can. Their biggest advantage is they have an aftermarket SFI certified case. So if they do have an internal failure, it will help contain the explosion. Being that the 727 we are discussing has a bolt in sprag and billet front drum, the main explosion risk is already addressed. He is simply asking about upgrading to hardened shafts. At his power level, and intended use, the stock shafts should be fine, but if he upgraded, he will never need to worry about it again.

Re: Big power & 727… input or output shaft the weak link? [Re: PLUM BAD] #3125849 03/02/23 09:31 AM 03/02/23 09:31 AM
Joined: Mar 2011 Posts: 3,075 Michigan A A727Tflite master
A727Tflite master A Joined: Mar 2011 Posts: 3,075 Michigan	Originally Posted by PLUM BAD I broke a hub two years ago. [/url][/img] And a band anchor last year. [/url][/img] Your hub broke due to the very common issue of hub to support interference. Notice the shiny area just above the break.

Re: Big power & 727… input or output shaft the weak link? [Re: B3422W5] #3125889 03/02/23 12:30 PM 03/02/23 12:30 PM
Joined: Jan 2003 Posts: 16,925 NC 440Jim I Live Here
440Jim I Live Here Joined: Jan 2003 Posts: 16,925 NC	Originally Posted by B3422W5 I remember being under your Dart getting it out….lol You helped me running a charger up to the lanes in later rounds Blast from the past. Eric on the back of my mini-bike, hauling a generator and charger to the staging lanes. From the date on this pic, it was 2005. It looked so funny, someone took a picture and gave it to us later... LOL 1993 Daytona, 5.50 at 130mph (1/8) 1.19 sixty ft (PG). Link to 572 B1 - Part 1

Re: Big power & 727… input or output shaft the weak link? [Re: A727Tflite] #3125927 03/02/23 02:52 PM 03/02/23 02:52 PM
Joined: Jan 2003 Posts: 2,697 Renton Wa T topfueldart OP master
topfueldart OP master T Joined: Jan 2003 Posts: 2,697 Renton Wa	Originally Posted by Transman Your hub broke due to the very common issue of hub to support interference. Notice the shiny area just above the break. Can you elaborate on this at all? Any specific cause, or just something to keep an eye out for? I imagine a thicker fiber washers would help push the hub back. 11.48 @ 120 with a 1.80 60' 318, stock 1.88 heads, stock 904, Pump Gas, 13 lbs of boost. 9.94 @ 134, 318 on pump gas, 14 lbs w/ Eddies, transbrake 727, 3600 lbs, 3.54 gear and 28's.

Re: Big power & 727… input or output shaft the weak link? [Re: topfueldart] #3125932 03/02/23 03:08 PM 03/02/23 03:08 PM
Joined: Mar 2011 Posts: 3,075 Michigan A A727Tflite master
A727Tflite master A Joined: Mar 2011 Posts: 3,075 Michigan	Originally Posted by topfueldart Originally Posted by Transman Your hub broke due to the very common issue of hub to support interference. Notice the shiny area just above the break. Can you elaborate on this at all? Any specific cause, or just something to keep an eye out for? I imagine a thicker fiber washers would help push the hub back. Edit - incorrect or broken #1 or 2 thrust, or mismatched parts. Notice the earlier picture of a truly broken hub, it has a rough appearance. The second image is a smooth break, like it was machined in a lathe. When first building the unit, place the empty support on the input assembly and see if there is interference. Last edited by Transman; 03/02/23 08:18 PM.

Re: Big power & 727… input or output shaft the weak link? [Re: topfueldart] #3126379 03/04/23 09:55 AM 03/04/23 09:55 AM
Joined: May 2003 Posts: 13,189 aZLiViN J J_BODY I Live Here
J_BODY I Live Here J Joined: May 2003 Posts: 13,189 aZLiViN	I think I have a good 727 input shaft and hub in the archives. I’ll look. I certainly don’t need it.

Re: Big power & 727… input or output shaft the weak link? [Re: 440Jim] #3126384 03/04/23 10:05 AM 03/04/23 10:05 AM
Joined: Jan 2003 Posts: 11,711 Portage,michigan B B3422W5 I Live Here
B3422W5 I Live Here B Joined: Jan 2003 Posts: 11,711 Portage,michigan	Originally Posted by 440Jim Originally Posted by B3422W5 I remember being under your Dart getting it out….lol You helped me running a charger up to the lanes in later rounds Blast from the past. Eric on the back of my mini-bike, hauling a generator and charger to the staging lanes. From the date on this pic, it was 2005. It looked so funny, someone took a picture and gave it to us later... LOL Haha….I remember seeing that years ago. You guys bailed me out that night! 69 Dart GTS A4 Silver All steel, flat factory hood, 3360race weight 418 BPE factory replacement headed stroker, 565 lift solid cam Best so far, 10.40 @127 1/4 1.41 best 60 foot 6.60 at 103.90 1/8

Re: Big power & 727… input or output shaft the weak link? [Re: topfueldart] #3126947 03/06/23 12:06 PM 03/06/23 12:06 PM
Joined: Jan 2003 Posts: 13,363 Marion, South Carolina [><] an8sec70cuda I Live Here
an8sec70cuda I Live Here Joined: Jan 2003 Posts: 13,363 Marion, South Carolina [><]	FWIW I still have the stock shafts in the 727 in my cuda. It's over 3800 lbs and ran mid 9s NA from 2006-2015 w/ no trouble. Been running 8s on nitrous ever since. I don't race it very often though. From what others have experienced, it wouldn't surprise me if it snapped something the next time I ran it. CHIP '70 hemicuda, 575" Hemi, 727, Dana 60 '69 road runner, 440-6, 18 spline 4 speed, Dana 60 '71 Demon, 340, low gear 904, 8.75 '73 Chrysler New Yorker, 440, 727, 8.75 '90 Chevy 454SS Silverado, 476" BBC, TH400, 14 bolt '06 GMC 2500HD LBZ Duramax

Re: Big power & 727… input or output shaft the weak link? [Re: an8sec70cuda] #3127442 03/08/23 02:22 AM 03/08/23 02:22 AM
Joined: May 2003 Posts: 13,189 aZLiViN J J_BODY I Live Here
J_BODY I Live Here J Joined: May 2003 Posts: 13,189 aZLiViN	I do have a 727 input hub assy

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