Notices
Series I Tech Garage The place to discuss anything technical about the RX-8 that doesn't fit into any of the categories below.

Welded Diff options?

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old 07-30-2010 | 04:04 PM
  #26  
dannobre's Avatar
Modulated Moderator
iTrader: (3)
 
Joined: Feb 2004
Posts: 13,719
Likes: 338
From: Smallville
Caution: Moron Speaking
Old 07-30-2010 | 04:22 PM
  #27  
RIWWP's Avatar
Registered
iTrader: (2)
 
Joined: Oct 2007
Posts: 16,684
Likes: 261
From: Pacific Northwest
Originally Posted by jasonrxeight
was it a power on into a corner or was it a off power into the corner?
I feel when off power turn in the corner, locked would give me a bit of understeer, and open diff would give me a bit of oversteer. as you get on power its the opposite. thats why LSD is for.
On or off power, if you are turning at all, the inside tire travels a shorter distance than the outside tire. If they can rotate independantly, then the inside tire will rotate slower and the outside tire will rotate faster so that they cover the different distances in the same period of time.


Locking the 2 together via a welded diff means that if you are turning, both tires are turning at the exact same rate, so one of the tires will have to rotate faster than it is traveling or slower than it is traveling. Usually, due to weight transfer, the outside tire has more grip, the inside tire less grip, so usually the inside tire rotates faster than the ground is passing under it. Even if it is by 1-2%, then HAS to mean there is tire slippage, and not a firm contact with the ground. Under these conditions, you have 2 tires up front that are gripping, but only 1 in the rear...


OVERSTEER!


In the best possible conditions no where near the limits of grip, this means extra tire wear and that's about it.

Approach the limits of grip, usually when in low traction conditions like rain, this means that your car will have a tendancy to snap oversteer with even slight steering input.


Perfect for drifting on the track


Perfectly stupid if you drive it on the street at all.


Can you survive it? Can you be lucky?

Sure. Just like you can play Russian roulette and not blow your brains out.
Old 07-30-2010 | 04:44 PM
  #28  
jasonrxeight's Avatar
Registered
 
Joined: Jan 2010
Posts: 3,487
Likes: 3
From: Omaha, NE
Originally Posted by RIWWP
On or off power, if you are turning at all, the inside tire travels a shorter distance than the outside tire. If they can rotate independantly, then the inside tire will rotate slower and the outside tire will rotate faster so that they cover the different distances in the same period of time.
.
with opendiff when you off power turn in, the outside wheel is more likely to turn then locked diff so you likely to oversteer.
on power situation is different because the power goes to the inside wheel the outside wheel cant brake loose so you have more understeer than locked diff.
locked diff distribute engine brake and power more evenly than open diff.


Originally Posted by RIWWP
Locking the 2 together via a welded diff means that if you are turning, both tires are turning at the exact same rate, so one of the tires will have to rotate faster than it is traveling or slower than it is traveling. Usually, due to weight transfer, the outside tire has more grip, the inside tire less grip, so usually the inside tire rotates faster than the ground is passing under it. Even if it is by 1-2%, then HAS to mean there is tire slippage, and not a firm contact with the ground. Under these conditions, you have 2 tires up front that are gripping, but only 1 in the rear...


OVERSTEER!
in a corner when a lot weight transfer, inside wheels dont really grip due to very low pressure, even this you make the inside wheel spinning like crazy, say using an open diff, it wont make the car oversteer. to make the car oversteer when a lot of weight transfter, you need to spin the outside wheel.

Last edited by jasonrxeight; 07-30-2010 at 04:51 PM.
Old 07-30-2010 | 05:06 PM
  #29  
dannobre's Avatar
Modulated Moderator
iTrader: (3)
 
Joined: Feb 2004
Posts: 13,719
Likes: 338
From: Smallville
Since we have a LSD..why is all this open diff talk relevant anyway

It's a stupid hacked way to do something that can be done properly...and likely cheaper than the cost of all the broken parts
Old 07-30-2010 | 05:28 PM
  #30  
paulmasoner's Avatar
Asshole for hire
iTrader: (1)
 
Joined: Jun 2006
Posts: 3,214
Likes: 3
From: Colfontaine, Belgium
Originally Posted by dannobre
Since we have a LSD..why is all this open diff talk relevant anyway

It's a stupid hacked way to do something that can be done properly...and likely cheaper than the cost of all the broken parts

Originally Posted by paulmasoner
what OEM is, and banter about under/oversteer is all beside the point. the point is, if for some reason you are going to do this, you'll likely have to figure it all out on your own. i doubt you'll find much support or help here for making such a dumb move


i hate being right lol

it keeps being said, but no one is home
Old 07-30-2010 | 05:45 PM
  #31  
dannobre's Avatar
Modulated Moderator
iTrader: (3)
 
Joined: Feb 2004
Posts: 13,719
Likes: 338
From: Smallville
Can't wait for the " Totaled my 8" thread that results from this one
Old 07-30-2010 | 05:48 PM
  #32  
paulmasoner's Avatar
Asshole for hire
iTrader: (1)
 
Joined: Jun 2006
Posts: 3,214
Likes: 3
From: Colfontaine, Belgium
Originally Posted by dannobre
Can't wait for the " Totaled my 8" thread that results from this one
Old 07-30-2010 | 07:24 PM
  #33  
RIWWP's Avatar
Registered
iTrader: (2)
 
Joined: Oct 2007
Posts: 16,684
Likes: 261
From: Pacific Northwest
Originally Posted by jasonrxeight
with opendiff when you off power turn in, the outside wheel is more likely to turn then locked diff so you likely to oversteer.
on power situation is different because the power goes to the inside wheel the outside wheel cant brake loose so you have more understeer than locked diff.
locked diff distribute engine brake and power more evenly than open diff.



in a corner when a lot weight transfer, inside wheels dont really grip due to very low pressure, even this you make the inside wheel spinning like crazy, say using an open diff, it wont make the car oversteer. to make the car oversteer when a lot of weight transfter, you need to spin the outside wheel.
You are missing 1 key fact. If 1 wheel is spinning too fast or too slow, doesn't matter, and is no longer maintaining a solid 1-to-1 contact patch with the road, then it does not have grip. I don't care if it is inside or outside, fast or slow, etc... It doesn't have grip.

If you have 2 tires on the front with grip, and only 1 tire on the rear with grip, you WILL have an oversteer condition. I don't care if it is braking, acceleration, neutral, left, right, whatever. The ONLY way you will not have an oversteer condition is if the demand of grip on the rear of the car is below what ONE tire can provide. If it is beyond that 1 tire, then you will lose the grip of that 1 tire that is trying to hold grip (since the other has already lost it due to the locked diff), and no grip on the rear = oversteer.

This is why drift cars often lock the diff, because as soon as you start turning the steering wheel, you immediately start losing grip on the rear, making it incredibly easy to start those drifts. You also keep both tires spinning as you slide, for that smoke some people care about. IF you put on really sticky tires, then instead of the rubber against the road slipped and breaking traction, you have an axle breaking. With a locked diff, SOMETHING has to give, if it's a tire, you have oversteer. If it's not a tire, you have broken equipment.


Our LSD means exactly that "Limited Slip". It allows 1 tire/axle to slip vs the other one for a limited amount so you can turn without the loss of grip of a locked diff. It's limited, because if it was open, then we would only get power down to 1 wheel, like 16 passenger vans, and that's stupid for performance.


Originally Posted by dannobre
Can't wait for the " Totaled my 8" thread that results from this one


100% agree. locking/welding the diff is like putting on slicks. Sure it may be fine for dry weather, or at least workable, but the first rain will equal a tree through the side of the car.
Old 07-30-2010 | 08:02 PM
  #34  
bse50's Avatar
#50
 
Joined: Nov 2007
Posts: 7,521
Likes: 11
From: Caput Mundi
What's the point? Instead of ruining a sports car why don't you just pick the right set-up? With just sway bars and the right wheel alignment drift can be ok.
Anyway since you already stated
[QUOTE=JPotta;3655225 I only have a half mile drive everyday so im not really worried about it. [/QUOTE]
that translates to "I don't care about the car\engine's health" then do whatever pleases you. A cheap 2 way lsd would do. Selling the rx8 and getting an mk1 mr2 would work wonders as well.
Old 07-30-2010 | 09:52 PM
  #35  
jasonrxeight's Avatar
Registered
 
Joined: Jan 2010
Posts: 3,487
Likes: 3
From: Omaha, NE
Originally Posted by RIWWP
You are missing 1 key fact. If 1 wheel is spinning too fast or too slow, doesn't matter, and is no longer maintaining a solid 1-to-1 contact patch with the road, then it does not have grip. I don't care if it is inside or outside, fast or slow, etc... It doesn't have grip.

If you have 2 tires on the front with grip, and only 1 tire on the rear with grip, you WILL have an oversteer condition. I don't care if it is braking, acceleration, neutral, left, right, whatever. The ONLY way you will not have an oversteer condition is if the demand of grip on the rear of the car is below what ONE tire can provide. If it is beyond that 1 tire, then you will lose the grip of that 1 tire that is trying to hold grip (since the other has already lost it due to the locked diff), and no grip on the rear = oversteer.

This is why drift cars often lock the diff, because as soon as you start turning the steering wheel, you immediately start losing grip on the rear, making it incredibly easy to start those drifts. You also keep both tires spinning as you slide, for that smoke some people care about. IF you put on really sticky tires, then instead of the rubber against the road slipped and breaking traction, you have an axle breaking. With a locked diff, SOMETHING has to give, if it's a tire, you have oversteer. If it's not a tire, you have broken equipment.


Our LSD means exactly that "Limited Slip". It allows 1 tire/axle to slip vs the other one for a limited amount so you can turn without the loss of grip of a locked diff. It's limited, because if it was open, then we would only get power down to 1 wheel, like 16 passenger vans, and that's stupid for performance.
.
blah blah blah. I cant be bothered anymore.
Old 07-30-2010 | 10:00 PM
  #36  
TeamRX8's Avatar
Registered
iTrader: (25)
 
Joined: Apr 2005
Posts: 26,866
Likes: 2,083
Originally Posted by dannobre
Caution: Moron Speaking

WTF, I didn't say a word.
Old 07-30-2010 | 11:03 PM
  #37  
yiksing's Avatar
the giant tastetickles
 
Joined: Sep 2005
Posts: 2,758
Likes: 0
From: in the basement
Get a clutch packed LSD from Kaaz, etc do it right.
Old 07-31-2010 | 12:11 AM
  #38  
dannobre's Avatar
Modulated Moderator
iTrader: (3)
 
Joined: Feb 2004
Posts: 13,719
Likes: 338
From: Smallville
Originally Posted by TeamRX8
WTF, I didn't say a word.


I thought that there would at least be a WOW
Old 07-31-2010 | 12:33 AM
  #39  
laythor's Avatar
I zoom therefore I am.
 
Joined: Mar 2007
Posts: 4,919
Likes: 12
From: San Jose, CA
don't do it just because your friends do it... worst reason ever to do anything
Old 08-01-2010 | 04:08 AM
  #40  
JPotta's Avatar
Thread Starter
Registered
 
Joined: May 2006
Posts: 131
Likes: 0
Oh this place is great! Thanks to those of you who are understanding but I guess I'll just go along with this ****. I go to events almost every weekend annnnnd I understand how a diff works so we really dont need to go over that. Its just an F-ing diff its not gonna ruin my car or kill me, it acts the same as a 2 way most of the time. (lets argue that fact)

Zoom you have never even heard of a welded diff till now so thanks for your input but ill be ok you can drive a welded diff on the street. One tire will skip a bit backing out of parking spaces or doing u-turns but its not a big deal.

Mike[piston eater] You are the most rational person on this forum, thanks for doing your best to help me out.

Paulmasoner... sadly youre probably right I'll just go to a drift forum and get some real input on this hopefully it works out.

The rest of you have fun with your cars. I'll post up some videos when I'm all done. For now im just out getting seat time.
Old 08-01-2010 | 04:20 AM
  #41  
JPotta's Avatar
Thread Starter
Registered
 
Joined: May 2006
Posts: 131
Likes: 0
Originally Posted by bse50
What's the point? Instead of ruining a sports car why don't you just pick the right set-up? With just sway bars and the right wheel alignment drift can be ok.
Anyway since you already stated

that translates to "I don't care about the car\engine's health" then do whatever pleases you. A cheap 2 way lsd would do. Selling the rx8 and getting an mk1 mr2 would work wonders as well.
Sorry normaly I wouldnt do this but....

I love my car, a lot. It's amazing to drive, every time I take it drifting I just tear it up and people are surprised how well it does for a low powered NA car. But i could really use a locked diff. Anyway I'm not gonna sell my car for a f***ing mr2.
Old 08-01-2010 | 04:24 AM
  #42  
paulmasoner's Avatar
Asshole for hire
iTrader: (1)
 
Joined: Jun 2006
Posts: 3,214
Likes: 3
From: Colfontaine, Belgium
Originally Posted by JPotta

Paulmasoner... sadly youre probably right I'll just go to a drift forum and get some real input on this hopefully it works out.

The rest of you have fun with your cars. I'll post up some videos when I'm all done. For now im just out getting seat time.
ya, you go do that

i wouldnt bother, you're still gonna get the same response because we all still think you're an idiot if you do this.

get all the seat time you can because the first time you loose traction you'd better hope its low speed, otherwise you could kiss your *** goodbye along with the car
Old 08-01-2010 | 04:25 AM
  #43  
JPotta's Avatar
Thread Starter
Registered
 
Joined: May 2006
Posts: 131
Likes: 0
Originally Posted by paulmasoner
If I'm not banned already I will be if i respond to this. I really wish you guys could come with me on some touge runs or come to a drift practice. I've never lost traction before so I'm sure it will really take me by surprise and I'll crash.
Old 08-01-2010 | 04:35 AM
  #44  
paulmasoner's Avatar
Asshole for hire
iTrader: (1)
 
Joined: Jun 2006
Posts: 3,214
Likes: 3
From: Colfontaine, Belgium
Originally Posted by JPotta
I really wish you guys could come with me on some touge runs
yeah, i'd like to have that on cam... theres nothing illegal in recording someone falling down a mountainside is there?

Originally Posted by JPotta
or come to a drift practice.
to what purpose? nothing to be seen there that will change anyones mind concerning how ******* ignorant it is to weld your rear end

Originally Posted by JPotta
I've never lost traction before so I'm sure it will really take me by surprise and I'll crash.
your sarcasm is wasted. i remember th rednecks in the 80's who thought this was the coolest **** ever to do this, and its all cool and fun in your HS parking lot. wait till yo hit a seam in the road on the highway in the rain. if you're still capable, come back then to apologize for being so stupid and stubborn
Old 08-01-2010 | 05:01 AM
  #45  
paulmasoner's Avatar
Asshole for hire
iTrader: (1)
 
Joined: Jun 2006
Posts: 3,214
Likes: 3
From: Colfontaine, Belgium
Originally Posted by JPotta
**** you *** hole, what have you ever done that makes you someone worth listening to. Have you ever driven a welded diff or even seen someone drive on one. It's not a ******* bomb in the rear end. I really wish you lived closer cuz im sure I would drive circles around you. Just dont bother posting on my thread if youre just gonna talk ****.
thanks for the unsolicited PM.

to answer your questions in order:
-well, at some point in the past i read and was shown in person how different differentials work. but last i checked, theres a a lot full of others who are CERTAINLY more qualified than me saying the same thing i am....

-yes i have drove a welded diff. and have done so in good and bad conditions at low and high speeds.

-if you lived closer i would have knocked some sense into you by now
Old 08-01-2010 | 05:24 AM
  #46  
JPotta's Avatar
Thread Starter
Registered
 
Joined: May 2006
Posts: 131
Likes: 0
ugggghhh I give up.
Old 08-01-2010 | 05:31 AM
  #47  
yiksing's Avatar
the giant tastetickles
 
Joined: Sep 2005
Posts: 2,758
Likes: 0
From: in the basement
Originally Posted by JPotta
ugggghhh I give up.
Lol don't give up, while I do not suggest/recommend anyone welding their diff, I do recognize its the cheapest way drifters do but think about it, why not save some money for a Kaaz LSD and you can tune the gripping power of the LSD while you learn to drift?

club4ag.com might have answer to your questions
Old 08-01-2010 | 05:38 AM
  #48  
JPotta's Avatar
Thread Starter
Registered
 
Joined: May 2006
Posts: 131
Likes: 0
thanks man, glad to have some positive input.


It's not that I'm against a 2 way or think a welded is better but it would certainly be better than my stock diff to get me by for now. Down the road a kaaz would be ideal but I feel there are other things that should come first for me right now.
Old 08-01-2010 | 05:52 AM
  #49  
bse50's Avatar
#50
 
Joined: Nov 2007
Posts: 7,521
Likes: 11
From: Caput Mundi
Originally Posted by JPotta
thanks man, glad to have some positive input.


It's not that I'm against a 2 way or think a welded is better but it would certainly be better than my stock diff to get me by for now. Down the road a kaaz would be ideal but I feel there are other things that should come first for me right now.
Your stock differential is better than a welded one, this is the truth. Welded differentials are ok if you need to induce snap oversteer but suck when trying to keep a line. Plus they're hazardous on the track\street\canyon runs.
As I stated earlier in this thread just work with your suspension settings (ie sway bars since they're cheap) and save the money to do it the rght way.
Even a 2way diff. should be considered for drifting\drag only, if you intend to track your car or have fun driving it around a 1.5way would be much better, especially if adjustable.
Old 08-01-2010 | 01:21 PM
  #50  
dannobre's Avatar
Modulated Moderator
iTrader: (3)
 
Joined: Feb 2004
Posts: 13,719
Likes: 338
From: Smallville
You seem to be missing the point......

If you weren't being so adamant about your very dangerous idea...and actually listened...maybe you wouldn't get so upset that we are telling you it is a stupid idea for the use you have stated

For a track only drift car..that you would not be driving on the street....go for it...It isn't the best solution...but it won't be catastrophic if something happens....or you at least will only hurt yourself

If you kill somebody by driving it on the street......especially after soliciting opinions in public...you would be fair game for any decent liability lawyer

You need to grow up......MAN UP I think a popular TV Judge says

Driving is a privilege...not a right....If you want a Drift/Track toy...buy one..but don't drive it on the street


You have already rated this thread Rating: Thread Rating: 0 votes,  average.

Quick Reply: Welded Diff options?



All times are GMT -5. The time now is 02:27 PM.