Welded Diff for Rally?

Hello, i guess I have a quick question..... Alright so currently I don't have the funds to afford a proper LSD for my 1987 xr4ti and my question is that, would I be better of welding the Open Diff so that i could have a sense and predict where the car will go? Vs a open diff where its just a one wheel peeler and you cant predict where it'll slide.

My only concern with a the welded diff (I daily drive the car) is that ill slide into every corner and that Ill just go through tries alot quicker since i think a welded diff would short of act like a spool?

So if any one has any experience in rallying a rwd car with a welded diff your wisdom would be much appreciated.

Thanks, Conner

All my experience with a welded diff on stage and DDing is with a Volvo 240, so everything may not transfer to the XR and the IRS.
DDing a welded diff is not the most fun, I've been doing it for about 3 months and I'm not tired of it yet. I'm not sure how well the Ford IRS and CVs would handle it though.
As far as a welded diff on stage, it's fine if you can get the car initiated.

If you can spring for the supra diff swap, that is a good way to go. I would look into a different mounting system though.

Quote
Robert Culbertson
All my experience with a welded diff on stage and DDing is with a Volvo 240, so everything may not transfer to the XR and the IRS.
DDing a welded diff is not the most fun, I've been doing it for about 3 months and I'm not tired of it yet. I'm not sure how well the Ford IRS and CVs would handle it though.
As far as a welded diff on stage, it's fine if you can get the car initiated.

If you can spring for the supra diff swap, that is a good way to go. I would look into a different mounting system . than the fucked up version that was on the cars you've glanced at.

helping you help the others out there again Culbertson...

---

John Vanlandingham
Sleezattle, WA, USA

Vive le Prole-le-ralliat

www.rallyrace.net/jvab
CALL +1 206 431-9696
Remember! Pacific Standard Time
is 3 hours behind Eastern Standard Time.

Great on stage, sucks ass on road. If you are DDing it, I'd leave it open.

---

Grant Hughes

Thanks for the reply guys i really appreciate it. Ive looked at supra diffs for sale but whenever I find them there just as expensive as a cosworth 4x4 diff.

So I don't really understand the point of buying one since I suspect the cosworth just bolts right up without making any brackets?

If I where to go down the supra route, down the road, does John V. Still make the mounting brackets and the half shaft adapters?

-Thanks, Conner



Edited 2 time(s). Last edit at 04/30/2015 02:23PM by cmanreinhart.

Quote
cmanreinhart
Thanks for the reply guys i really appreciate it. Ive looked at supra diffs for sale but whenever I find them there just as expensive as a cosworth 4x4 diff.

So I don't really understand the point of buying one since I suspect the cosworth just bolts right up without making any brackets?

If where there to go the supra route down the road, does does John V. Still make the mounting brackets and the half shaft adapters?

-Thanks, Conner

Just dropped off another 24 CV adaptors for zinc plating day before yesserdee.

The point of the Supra diff over the Cossie diffs is very simple..

a) available at better wrecking yards Nation wide.in Craigslists too. .Post your Zip and I'll find ya one.

b) VERY MUCH STRONGER...simply no comparison..even the 7.5 diff is only just "OK" and

B 1/2) its a clutch plate diff that YOU can fuck with and set it up stiffer....VC er nope.

c) more important: Toyotter 8" ring and pinion available in all kinds of ratios. New is cheap, second hand is cheap...I've seen guys selling "drop outs" or center sections from 4-runners with 4.8 ratios for $100..so you get that for a hun and stick it in the Sooop-rah diff when you have to be non turbo, and later stick a 4.3 when you go turbo...

You understand what an advantage and how much effect short gears means for the fun factor?

As privateers we want a nice MARGIN of safety. or reliability..same thing..

So in one fell swoop, you get strength, flexibility, performance and even if you pay $300 that ain't shit in todays money...

Post your zip...

---

John Vanlandingham
Sleezattle, WA, USA

Vive le Prole-le-ralliat

www.rallyrace.net/jvab
CALL +1 206 431-9696
Remember! Pacific Standard Time
is 3 hours behind Eastern Standard Time.

Quote
john vanlandingham
Just dropped off another 24 CV adaptors for zinc plating day before yesserdee.

The point of the Supra diff over the Cossie diffs is very simple..

a) available at better wrecking yards Nation wide.in Craigslists too. .Post your Zip and I'll find ya one.

b) VERY MUCH STRONGER...simply no comparison..even the 7.5 diff is only just "OK" and

B 1/2) its a clutch plate diff that YOU can fuck with and set it up stiffer....VC er nope.

c) more important: Toyotter 8" ring and pinion available in all kinds of ratios. New is cheap, second hand is cheap...I've seen guys selling "drop outs" or center sections from 4-runners with 4.8 ratios for $100..so you get that for a hun and stick it in the Sooop-rah diff when you have to be non turbo, and later stick a 4.3 when you go turbo...

You understand what an advantage and how much effect short gears means for the fun factor?

As privateers we want a nice MARGIN of safety. or reliability..same thing..

So in one fell swoop, you get strength, flexibility, performance and even if you pay $300 that ain't shit in todays money...

Post your zip...

I gotcha that makes a lot more since now... Now what ratio would I want to go for? I've seen

build threads where guys use the 4.10 gear from a supra. ( I don't know the specific years Toyota

put that ratio in them, I'm suspecting the Mk3 area?) And yeah I hear what your saying John on

how $300 "ain't shit in today's money" and compared to what it would cost for other cars. The

welded diff solution only came to mind since i was looking for a cheap alternative (since my

parents are trying to get me to save for college). But ehh who needs to college.... I rather

just live in the woods and rally all day. But wouldn't we all, whatev...

Oh and my Zip John is: 48152

And thanks in advanced for looking one up for me!

-Thanks, Conner

Quote
john vanlandingham

helping you help the others out there again Culbertson...

It's not terrible, it works... it could just be easier. If the rear mounts had the bolts going vertical, instead of fore/aft it would not over constrain the mount. It would be SO MUCH EASIER to drop the diff. It wouldn't involve a pry bar or a hammer. You can literally remove all the bolts from the mount and the diff will stay in there (on both XRs I've been around). I had to set the rear upper mount with a slight gap so it wouldn't mind going in or out. Works much moah better, but it now pulls the rear of the chassis forward as the bolts are tightened (not a real issue though).

Also, to make the supra CV adapters work a little easier I had to drill the holes a bit larger using a sharp drill bit (maybe 0.008in or so). It looks like they were originally done with a itty bitty post hole digger

Quote
Robert Culbertson
DDing a welded diff is not the most fun, I've been doing it for about 3 months and I'm not tired of it yet. I'm not sure how well the Ford IRS and CVs would handle it though.

Just got done driving my car home from a friend's garage after installing a welded diff and innovative new one piece axles. Feels almost exactly like driving with the clutch pack diff. Only difference is that the clutch diff would sometimes (but not always) slip in tight turns when off the power, and it would lock up again with the slightest amount of power, so drivability was weird. With the welded you always know what you're going to get so it is at least consistent.

---

Pete Remner
Cleveland, Ohio

1984 RX-7 (rallycross thing)
1978
Silence is golden, but duct tape is silver.

1986???
Carrier
Toyota Supra HAS 6 BOLT AX HAS 6 BOLT AXLE FLANL A 090096 $150 Nationwide Auto Parts & Recycler USA-OH(Toledo) Request_Quote 1-800-962-9075 Request_Insurance_Quote
55 miles from your zip.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Little pricy but not to far
1987
Carrier
Toyota Supra REAR-PIG-ASS,TURBO,49608 4L4486 $350 Gene's Auto Parts-Traverse City USA-MI(Traverse-City) Request_Quote 1-888-228-9373 Request_Insurance_Quote 198 miles


All automatics all years MkIII MA70 had 4.3---what you want----both turbo and non turbo..
ALL turbo came OEM LSD
Many non turbos were LSD
5 speed non turbo ......4.3 ratio
5 speed early turbo......3.9 ratio
Later 5 speed turbo.......3.73
auto turbo....................4.3
auto non turbo..............4.3

With the typically taller rally tires get a 4.3... can't find one easily I have and extra 5-6 units...


anothe
1989
Carrier
Toyota Supra RWD, A 695-Q $350!!! Yikes!!!Tiger Auto Salvage, L.L.C. USA-MI(Burton) Request_Quote 800-743-0106 / 810-743-7400 Request_Insurance_Quote
40 miles away

Gotta consider that UPS from here would be around $85-90

so ..................

Holy shit!

1991
Carrier
Toyota Supra 7073 $100 Mitch's Auto Parts, Inc. USA-MI(Detroit) Request_Quote 313-365-4844 Request_Insurance_Quote
17 miles


http://www.car-part.com/

search for "carrier"

---

John Vanlandingham
Sleezattle, WA, USA

Vive le Prole-le-ralliat

www.rallyrace.net/jvab
CALL +1 206 431-9696
Remember! Pacific Standard Time
is 3 hours behind Eastern Standard Time.

Damn John nice find! One last question, do I have to to shorten my driveshaft to accommodate the supra diff? Because I literally just got mine shortened a month ago...

-Conner

Quote
cmanreinhart
Damn John nice find! One last question, do I have to to shorten my driveshaft to accommodate the supra diff? Because I literally just got mine shortened a month ago...

-Conner

Conner,

The overall drive shaft length will be the same length down to the thickness of a certain type of hair. You will need to change out the flange since you will need toyota specific with the supra diff.

Something like

Spicer 2-28-417
plus
Neapco N2-2-799-1
plus
some 1310 u-joint

Should do it.

Just from driving rallies with a welded RWD diff back in the day..... if the rears get on a better grip surface and the fronts are off in the trash, the rears can hook up really well and the car will shoot striaght ahead if you put on the gas lightly to moderately (i.e., not enough to get the rear loose).....which may not be the direction in which you need to be going at that moment!

I found that you need to be willing to throw the car hard into each corner, and if the car went straight when you wanted it to turn, then you either needed more rear brake to loosen the rear or go the other way and be brave on the gas...the latter is not what newer really drivers have in abundance in a panic situation. So, you need to have some bigger rear brake bias and/or a hydraulic handbrake and know how to use it, and/or some HP and know how and be brave enough to use it, or this may end up causing a not-so-good surprise at some point on stage. A heavier rear sway bar woudl make it easier to throw the car sideways into the corners. Low HP or a turbo not spooled up would perhaps be more of an issue too, since it would be harder to get the rears loose despite the maximum level of bravery!

I took the welded diff out but it probably would have been better if I had understood the issue better and had put in the higher rear brake bias and the large rear sway bar that went into the car later on.



Edited 1 time(s). Last edit at 06/04/2015 09:53AM by starion887.

Quote
Thomas Kimsey

Quote
cmanreinhart
Damn John nice find! One last question, do I have to to shorten my driveshaft to accommodate the supra diff? Because I literally just got mine shortened a month ago...

-Conner

Conner,

The overall drive shaft length will be the same length down to the thickness of a certain type of hair. You will need to change out the flange since you will need toyota specific with the supra diff.

Something like

Spicer 2-28-417
plus
Neapco N2-2-799-1
plus
some 1310 u-joint

Should do it.

Thanks Thomas, I'm definitely going to look into the supra diff. I just threw a T-9 in my Xr and it still has the auto diff in it and man is it doggie. I looked over your build thread and noticed you put a 4.3 supra diff in your Xr how do you like it? Im thinking I might go with the 3.93 since I'll probably just being doing autocrosses with it.

Quote
cmanreinhart

Quote
Thomas Kimsey

Quote
cmanreinhart
Damn John nice find! One last question, do I have to to shorten my driveshaft to accommodate the supra diff? Because I literally just got mine shortened a month ago...

-Conner

Conner,

The overall drive shaft length will be the same length down to the thickness of a certain type of hair. You will need to change out the flange since you will need toyota specific with the supra diff.

Something like

Spicer 2-28-417
plus
Neapco N2-2-799-1
plus
some 1310 u-joint

Should do it.

Thanks Thomas, I'm definitely going to look into the supra diff. I just threw a T-9 in my Xr and it still has the auto diff in it and man is it doggie. I looked over your build thread and noticed you put a 4.3 supra diff in your Xr how do you like it? Im thinking I might go with the 3.93 since I'll probably just being doing autocrosses with it.

the 4.3 ratio is intended to be optimum in the UPPER gears of the box...so the car's acceleration in 3rd and 4th is harder ---just where most car's box/axle combo wants quite low rev "cruise'

IF you intend ever to go in the woods, compromise the wawwy-closs stuff now so better in woods.
Wawwy closs isn't important to get everything "pretty dam good", just don't over-drive...

Buy the right thing once...

And you should talk--phone--Thomas and his house mate Graham---they crack up talking about burying cars near the edge of the wawwy-closses since installing the 4.3 Supra diff...not scooops of mud, whole wheel barrow loads..

---

John Vanlandingham
Sleezattle, WA, USA

Vive le Prole-le-ralliat

www.rallyrace.net/jvab
CALL +1 206 431-9696
Remember! Pacific Standard Time
is 3 hours behind Eastern Standard Time.