welded rear diff?

[97-TSi-Hx35]

has anyone welded a dsm rear diff to make it a solid spool, is it possible? I have seen many posts about people talking about it but I dont see any others trying this for drag cars?

 

[sparky1987]

I haven't tried to weld a rear diff but I know when taking turns it makes the tires chirp because it wont let the tires spin at different speeds. It also causes alot of stress on the gears. In the diff.

 

[TurboATM]

Ive been thinking about this in my All Trac, but decided against it...normal driving will make the rear end tail happy...Even my 240 friends dont like their welded rear diff for street driving.

 

[bryanwheat]

The factory lsd is plenty sufficient for most people.

 

[BoostedTalonTS]

has anyone welded a dsm rear diff to make it a solid spool, is it possible? I have seen many posts about people talking about it but I dont see any others trying this for drag cars?

The ONLY thing that I would even consider welding in an AWD car would be the center diff. This will give you a 50-50 torque split between front & rear... Once this is done, THEN you can start talking about welding the front & rear diffs.

 

[CanadianTalonTC]

The ONLY thing that I would even consider welding in an AWD car would be the center diff. This will give you a 50-50 torque split between front & rear... Once this is done, THEN you can start talking about welding the front & rear diffs.

Welding the center diff will still not give you a true 50/50 torque split due to transmission losses being different from the front diff in the transaxle to the rear diff.

Also welding the front diff is a terrible idea. Enjoy lack of turning haha.

Joel

 

[TurboATM]

Welding the center diff will still not give you a true 50/50 torque split due to transmission losses being different from the front diff in the transaxle to the rear diff.

Also welding the front diff is a terrible idea. Enjoy lack of turning haha.

Joel

...but its going to spin all 4 wheels, at the same thing, which is a MAJOR thing when drag racing.

 

[Lofty]

If you weld your front diff and it does come apart it will take you into the wall on the track, and even worse with street driving.

A welded rear will cause HELL on your drivetrain, and I don't deem it necessary, you're not trying to drift, are you?

Only diff I'd weld would be center.

 

[CanadianTalonTC]

...but its going to spin all 4 wheels, at the same thing, which is a MAJOR thing when drag racing.

An LSD in the front is a much better option to welding it if that's what your going for.

Joel

 

[jtmcinder]

Welding the center diff will still not give you a true 50/50 torque split due to transmission losses being different from the front diff in the transaxle to the rear diff.

I wish that you'd stopped after the first phrase.

For the umpteenth time, a welded diff is no longer a diff. Because of that, it has no meaningful "torque split" any more. It can produce anything from 100/0 to 0/100, depending on which end of the car has more grip.

http://www.dsmtuners.com/forums/newbie-forum/410949-awd-dsm-torque-split-distribution.html

 

[BoostedTalonTS]

Welding the center diff will still not give you a true 50/50 torque split due to transmission losses being different from the front diff in the transaxle to the rear diff.

Also welding the front diff is a terrible idea. Enjoy lack of turning haha.

Joel

Although you are technically correct in terms of additional drivetrain loss(es) incurred the further you get from the crankshaft, it is the closest thing you will get to 50/50 in these cars my friend... Trust me, I know what its like DD'ing on a welded center. Like I said in my original post, the center diff is the only thing that I would consider welding.

Once you start making any real power in these things (especially the AT AWDs) the viscous coupler is usually the first thing to go out. At this point, I considered Shep's 4 spider center, but the additional $1200 for it was just a little too steep for me.

 

[jtmcinder]

Although you are technically correct in terms of additional drivetrain loss(es) incurred the further you get from the crankshaft, it is the closest thing you will get to 50/50 in these cars my friend...

Stop. Please. Do not say that welding gives you a 50/50 split again. Welding is as far from 50/50 as you can get, since it can be anything from 100/0 to 0/100. The OE spider was a 50/50 split.

 

[CanadianTalonTC]

I wish that you'd stopped after the first phrase.

For the umpteenth time, a welded diff is no longer a diff. Because of that, it has no meaningful "torque split" any more. It can produce anything from 100/0 to 0/100, depending on which end of the car has more grip.

http://www.dsmtuners.com/forums/newbie-forum/410949-awd-dsm-torque-split-distribution.html

Good read there for sure. Thank you for the link.

Physics says that there is still more torque being transferred to the front wheels due to the engery consumed by transferring the it 90 degrees even while it's splitting it "50/50".

That being said, it's assuming that all four tires have equal grip in that situation.

Joel

 

[BoostedTalonTS]

Stop. Please. Do not say that welding gives you a 50/50 split again. Welding is as far from 50/50 as you can get, since it can be anything from 100/0 to 0/100. The OE spider was a 50/50 split.

True, however there is still the problematic viscous coupler that is driving the center diff... The only way to eliminate it is by welding the center diff & using a VCE kit. By doing so it makes the car have a more even F/R torque bias, but don't just take my word for it... Ask John over at IPT about why they only offer the W4A33 race built trans with a welded center diff (that is of course if you'd want the $1200 Shep 4 spider diff option).

 

[97-TSi-Hx35]

I'm buildings a tralier queen for drag racing, I welded the center diff last season and I'm looking for more traction with out the cost of replacing my entire rear end with an LSD unit or the crazy cost of the drop in units.

 

[clipto]

If its a track queen then It's fine just welding the diff, still a pain to push or move tho, and is totally not cool daily driven .

 

[jtmcinder]

True, however there is still the problematic viscous coupler that is driving the center diff... The only way to eliminate it is by welding the center diff & using a VCE kit. By doing so it makes the car have a more even F/R torque bias, but don't just take my word for it... Ask John over at IPT about why they only offer the W4A33 race built trans with a welded center diff (that is of course if you'd want the $1200 Shep 4 spider diff option).

I don't need to ask anyone to know that welding a diff makes it have no meaningful torque split BECAUSE IT ISN'T A DIFF ANYMORE.

 

[TurboATM]

What happens with the OEM open Diff
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What happens when you weld the center solid.
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[97-TSi-Hx35]

I don't need to ask anyone to know that welding a diff makes it have no meaningful torque split BECAUSE IT ISN'T A DIFF ANYMORE.

My center diff has been welded for over a season of racing and I am not interested in having any sort of differential in the rear, as long as the front is open so I can turn left before the sand I don't care about drivability .

 

[BoostedTalonTS]

What happens with the OEM open Diff
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What happens when you weld the center solid.
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...couldn't have said it any better myself.

I don't need to ask anyone to know that welding a diff makes it have no meaningful torque split BECAUSE IT ISN'T A DIFF ANYMORE.

By your 'logic' then, these guys have no idea of what they are doing, eh? WTF

Welded Center Differential for Mitsubishi / DSM AWD Automatic Transmissions

 

[jtmcinder]

I try to avoid inferring what vendors know from what they say in their ads. It is quite likely that the vendor in question is completely aware that a welded "diff" is no longer a diff and, therefore, has no meaningful torque split. But, because said vendor is trying to sell stuff to people who think that welded "diffs" have 50/50 splits, they go ahead and say so in their ads. They are probably as aware as I am that certain people will never understand torque split vs torque distribution and they have stopped trying to explain it (as I will soon).

In other words, no, I'm not going to take your bait into making me argue with that vendor. I have said what needed to be said and will leave it to you to become educated or remain a member of the Great Unwashed.

And with all that said, can you please stop going on about (and posting videos about) welded centers in a thread that is about welded rears. If you can't keep which diff is under discussion straight, it's no wonder you have no idea that torque split and torque distribution are different.

 

[97gst_spyder]

My center diff has been welded for over a season of racing and I am not interested in having any sort of differential in the rear, as long as the front is open so I can turn left before the sand I don't care about drivability .

You sound dumb.....

 

[jtmcinder]

You sound dumb.....

That you would say this says more (bad) things about you than about the OP.

It actually makes sense for a dedicated drag car to have a welded center and rear, as long as the front is open so that the car can still be turned. What the OP said is fine. What you said was not.

 

[99gst_racer]

has anyone welded a dsm rear diff to make it a solid spool, is it possible? I have seen many posts about people talking about it but I dont see any others trying this for drag cars?

Shoot a PM over to viperlp01. I'm pretty sure he's rocking a welded center and rear in his 2G.

 

[97-TSi-Hx35]

[/B]
You sound dumb.....

I'm sorry I confused you with all those big words like, differential and weld, For no farther confusion lets keep it simple for you.

I want to know feedback from people that drag race about a rear solid spool.