Author Topic: REAR ENDS - OPEN, SPOOL or LOCKER??  (Read 24262 times)

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Offline floydjer

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REAR ENDS - OPEN, SPOOL or LOCKER??
« on: February 04, 2008, 10:20:59 AM »
Greetings....A noob w/ a question. What type of dif. is preferred and why? If this has been covered already, please steer me in the right direction. Thanks in advance.   Jerry
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Offline jimmy six

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Re: Open differential or locked?
« Reply #1 on: February 04, 2008, 12:16:45 PM »
This has been covered many times and I don't know where tyo find it in the site.

With that said long wheel base cars seem to live with anything. With all others: if you have a locked rear and spin, take it out. if you don't have one and spin, put one in..........Listening and learning over the years...JD
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Offline SPARKY

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Re: Open differential or locked?
« Reply #2 on: February 14, 2008, 11:47:52 AM »
JD---this is a good example of why you should keep posting---and not go ONLY pm---thanks for your input!!!!!!!!!!
Miss LIBERTY,  changing T.K.I.  to noise, dust, rust, BLUE HATS & hopefully not scrap!!

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Offline Pat Kinne / Salt201

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REAR ENDS - OPEN, SPOOL or LOCKER??
« Reply #3 on: March 19, 2008, 08:30:06 AM »
     Having run an open rear-end in a short wheelbase Monza with some sucess , A spool or locked rear end in a variety longer wheelbased cars, again with some sucess, we tried a "locker type" configuration as recommened by the Winters Rear End people.  We had problems right off the starting line with what seemed to be the locker sending power from one wheel to the other - not a good deal. I am not sure what brand of "locker" they put in the quickchange but it sure didn't work for us.
     Has anyone else had a good expierence with type of "traction control??   - Pat Kinne

Offline doug odom

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Re: REAR ENDS - OPEN, SPOOL or LOCKER??
« Reply #4 on: March 19, 2008, 11:53:23 PM »
Pat, To my way of thinking, run an open or spool. When a locker screws up it really is a hand full. Been there, done that.   lol    Doug Odom in big ditch
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Offline SPARKY

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Re: REAR ENDS - OPEN, SPOOL or LOCKER??
« Reply #5 on: March 20, 2008, 12:41:21 AM »
Pat, When I spun my Lakester in '05 at El Miriage---I went around asking as many people as I could find that I knew to have be around for a while, about "OPEN" or "SPOOL". 

The bottom line consenus was:  If you have a spool and have problems---switch to an OPEN- :-D-If you are open and have problems  switch to a SPOOL!!!! :-D!!!!!  I would like to add if you have done all of the above and are still having problems- :evil: :evil:-check your "SCRUB RADIUS"---I hope that this solves the problem, as I have tried it both ways!!!!!!!!!!!  LOL
Miss LIBERTY,  changing T.K.I.  to noise, dust, rust, BLUE HATS & hopefully not scrap!!

"Security is mostly a superstition. It does not exist in nature, nor do the children of men as a whole experience it. Avoiding danger is no safer in the long run than outright exposure. Life is either a daring adventure or nothing."   Helen Keller

We are going to explore the racing N words NITROUS & NITRO!

Offline Roadster943

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Re: REAR ENDS - OPEN, SPOOL or LOCKER??
« Reply #6 on: March 20, 2008, 03:10:37 AM »

 I too have asked around and got the same response as Sparky. What works for me may be totaly wrong for you. I run a spool and am happy at this point. Vince
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Offline Joe Timney

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Re: REAR ENDS - OPEN, SPOOL or LOCKER??
« Reply #7 on: March 20, 2008, 05:53:06 AM »
I would not recommend a locker...still shuttering from a triple loop 30 years ago. If a quick change customer wants an open dif, I recommend the Winters Track, it is a worm style posi without clutches. It senses which tire has the bite and applies the power to it. For what it's worth!!!
joe
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Offline Pat Kinne / Salt201

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Re: REAR ENDS - OPEN, SPOOL or LOCKER??
« Reply #8 on: March 20, 2008, 10:05:19 AM »
   Thanks guys - Thats how this forum is suppposed to work - good information from people that have been there and done that - Great.
   The bottom line is that we will be going to a locked rear end for this year - all things concidered, we know that will work and get you done the track. Your point of "problems with spool change to open - problems with open change to spool" is well taken - Thanks for participating - Pat

Offline doug odom

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Re: REAR ENDS - OPEN, SPOOL or LOCKER??
« Reply #9 on: March 20, 2008, 12:12:21 PM »
Pat, I know you know this but for anyone new there are other things that effect the rear tires also. Be sure that both rear tires are the exact same circumference and air pressure. Weigh the car on 4 scales to be sure you don't have any cross weight. Your not going to pitch it into a corner so cross weight is bad. check toe on the rear axle also.
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Offline 1 fast evo 2

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Re: REAR ENDS - OPEN, SPOOL or LOCKER??
« Reply #10 on: March 20, 2008, 10:47:39 PM »
I was just reading along but the last comment about checking rear toe got my attention. What is rec. for rear toe for bonneville in a sedan bodied car ?
                                 
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Re: REAR ENDS - OPEN, SPOOL or LOCKER??
« Reply #11 on: March 21, 2008, 12:27:12 AM »
What about us FWD guys?  :lol:

I started in 2004 with a welded diff (no money) and it worked great with 160 HP to the wheels. I got some cash and bought a quaiffe LSD. This was in 2005 and I had 540 HP to the wheels and the salt was god-awful. As I hit soft spots and hard sports with each front tire, the car would dart off to the other side due to power being put onto the "good" wheel. I literally almost hit the 3 mile marker and the 5 mile marker flags. I got out of the car shaking. In 06 I changed to a spool (welded diff + cash = spool) with 540 HP again and blew the motor up before I got a definitive answer to the question. I have since talked to a few other high HP FWD guys and they swear by open difs.

In short, All I know for sure is that the salt sucked in 2005 so I am going to try the spool again this year as it's already installed in the trans.
« Last Edit: March 21, 2008, 12:29:25 AM by John Romero »

Offline 836dstr

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Re: Open differential or locked?
« Reply #12 on: March 21, 2008, 02:14:13 PM »
Topics like this are what makes this Forum GREAT.

Coming from a Drag Race background I had preconceived ideas that a Posi was best. I run a 300" carb'ed gas engine so less affected by large torque #'s. I'm running a 700R4 with 4:88's. Worked good @ Bonneville but at El Mirage if I have to lift in OD the engine drops off the curve and will not recover @ top end.

I talked with Mark @ Pro Gear about building a third member with a 3:40 gear set and only using the first 3 gears @ ElMo. He asked me why I wanted a "Posi" which caused me to pause. He said that the majority of guys are running open rearends so that's what I'm running this year.

Like JD says, if it doesn't work I can always switch back.

We had a Club guy with a real torque monster. Always wanted to go left. They were running a Posi. At Bonneville 2 years ago they pulled the Posi and went to an open Dif. Still had the problem. Turns out the tires were mismatched. Went to another set that were matched for circumfrence and went straight.

So many variables!

Tom

Offline Sumner

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Re: Open differential or locked?
« Reply #13 on: March 21, 2008, 02:54:40 PM »
Topics like this are what makes this Forum GREAT.

.................................I talked with Mark @ Pro Gear about building a third member with a 3:40 gear set and only using the first 3 gears @ ElMo. ...............Tom

I'll bet you do better.  I have a 700R4 in my truck and love it, but the  30% drop on the 3-4 shift is a killer.  I recently got a 4L80E rebuilt that will go in the truck next winter with the anticipation of running it for time only.  When I do I'll change rear gears and just run the first 3 like you are talking about.

c ya,

Sum

John Romero

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Re: Open differential or locked?
« Reply #14 on: March 21, 2008, 03:06:46 PM »