: Posi install questions!



CadillacSTS42005
02-07-07, 11:26 AM
I plan on doing this with my spare tranny so as not to be down a car...
i know about all the pluses, but are there any downsides with adding a posi to these cars which are so dang computer oriented? any minuses at all?

BodybyFisher
02-07-07, 11:42 AM
I plan on doing this with my spare tranny so as not to be down a car...
i know about all the pluses, but are there any downsides with adding a posi to these cars which are so dang computer oriented? any minuses at all?

There is a member (MARK 99STS) over at caddyinfo.com that put a Limited Slip Differential on his Seville, see his web site here:
http://www.markonemtg.com/marks99sts/index.html

Look at that site and you will be amazed what he did. You might send him an email and ask him about the LSD, he is a nice guy. I believe he is a member here too, Mike

CadillacSTS42005
02-07-07, 01:24 PM
oh i know all about it
im ordering mine from the same company
i just wanted to know if there are any downfalls to this?
like worse manverability, t/c abs light, etc etc etc...

BodybyFisher
02-07-07, 01:38 PM
oh i know all about it
im ordering mine from the same company
i just wanted to know if there are any downfalls to this?
like worse manverability, t/c abs light, etc etc etc...

Have you spoken to Mark? I had the pleasure to speak to him a few times. I would contact him if I were you...

CadillacSTS42005
02-07-07, 01:42 PM
guess i really should
whats his web site again i have it bookmarket at home but im up at school now...

dkozloski
02-07-07, 01:55 PM
guess i really should
whats his web site again i have it bookmarket at home but im up at school now...
With a positive slip differential you can have unbelievable amounts of understeer right into the guard rail on slick roads whether you're on or completely off the power. On rutted roads or uneven roads it can steer like you're on the trolly tracks. Other than that you ought to be okay.

BodybyFisher
02-07-07, 02:15 PM
guess i really should
whats his web site again i have it bookmarket at home but im up at school now...

I gave you the link in my first post above, Mike

CadillacSTS42005
02-07-07, 10:49 PM
ty much
so in English this would be a BAD thing for maneuvering but a good thing for going in a staight line quicker lol

dkozloski
02-07-07, 11:22 PM
ty much
so in English this would be a BAD thing for maneuvering but a good thing for going in a staight line quicker lol
What it can do is make both front wheels break loose at the same time which means you can't steer. It can also force both wheels to turn the same speed over uneven road which makes the steering wheel snatch from side to side.

CadillacSTS42005
02-07-07, 11:39 PM
damn...
maybe this is a bad idea lol

AaronZ34
02-07-07, 11:41 PM
Posi /= LSD

CadillacSTS42005
02-07-07, 11:51 PM
thank god the mods blocked him so i cant read this...

dkozloski
02-08-07, 12:14 AM
No, its a good idea but it isn't all peaches and cream. It's something you have to get used to and anticipate what it's going to do. Positraction in an ordinary rear wheel drive can surprise you as well. Once you get used to it and understand what it's doing it's no problem.

CadillacSTS42005
02-08-07, 12:24 AM
my TA is posi and i like the better movement in the event of being stuck...
just wanted to make sure id get no idiot lights and such
and just a quick ? if i put a posi on this how the heck would the car have the t/c on and upshift into 2nd? i mean it does this when one wheel is spinning faster than the other would a posi take away from this?

dkozloski
02-08-07, 01:26 AM
my TA is posi and i like the better movement in the event of being stuck...
just wanted to make sure id get no idiot lights and such
and just a quick ? if i put a posi on this how the heck would the car have the t/c on and upshift into 2nd? i mean it does this when one wheel is spinning faster than the other would a posi take away from this?
I don't think you have anything to worry about.

Odin8
02-08-07, 02:34 PM
Was just reading this over and thinking about it some more. Would having an LSD interfer with the stabilitrak system's ability to independently brake the front wheels? You know, how if you're say, taking a left corner and your ass end starts sliding out, it'll brake the front right wheel to counter it and straighten the car out. If it had an LSD, wouldn't that force both wheels to brake, getting rid of any ability to control the car that way? Just thinking out loud.

dkozloski
02-08-07, 03:04 PM
Was just reading this over and thinking about it some more. Would having an LSD interfer with the stabilitrak system's ability to independently brake the front wheels? You know, how if you're say, taking a left corner and your ass end starts sliding out, it'll brake the front right wheel to counter it and straighten the car out. If it had an LSD, wouldn't that force both wheels to brake, getting rid of any ability to control the car that way? Just thinking out loud.
A Limited Slip Differential doesn't lock the wheels together like a Detroit Locker or LokRite. Worst case they'll still move somewhat. It's worth a try.

mtflight
02-08-07, 09:12 PM
What it can do is make both front wheels break loose at the same time which means you can't steer. It can also force both wheels to turn the same speed over uneven road which makes the steering wheel snatch from side to side.

That ought to get the adrenaline pumping!

jimfulco
02-09-07, 12:35 AM
On rutted roads or uneven roads it can steer like you're on the trolly tracks. Other than that you ought to be okay.

Mine already does this, more so the closer you get to WFO. You mean they don't all do it?

darien99
02-11-07, 03:07 PM
It won't interfere with traction control (it will aide this), and it won't interfere with abs. All this differential is doing is helping both wheels accelerate at about the same speed. Electronics will not cause a fuss.
You can always achieve something similiar to lsd in a fwd just by playing with air pressure in the tires and distributing weight alittle differently. It's not hard to get both tires to spin close to equal on a fwd.

dkozloski
02-11-07, 04:30 PM
It won't interfere with traction control (it will aide this), and it won't interfere with abs. All this differential is doing is helping both wheels accelerate at about the same speed. Electronics will not cause a fuss.
You can always achieve something similiar to lsd in a fwd just by playing with air pressure in the tires and distributing weight alittle differently. It's not hard to get both tires to spin close to equal on a fwd.
Only if they're on the same surface.

darien99
02-11-07, 06:12 PM
Yes, I'm speaking from a dry road/race track perspective.