Welded diff for maximum lockup

[The Wind Breezes]

Maybe I'm on crack here, but a thought just occurred to me:

Normally for track use I'm in favor of having a really high lockup on acceleration for solid manipulation under power, and a really low lockup (open diff) under braking for stability and turn in. In other words, a 1 way LSD.

But, 1 ways aren't as good for drifting, and I've become more interested in drifting lately. So, why not just weld my diff? I'm aware that this will, with all other things being equal, increase understeer on turn-in and oversteer at the limit. More importantly, it may bring some issues if I need to maneuver the car in a tight space. We'll see, they're not supposed to be as bad for that as a welded front diff. I do drive the car every day, but it is not my only means of transportation.

A big factor here is I can pull the diff, weld it, and reinstall it all for the cost of electricity, welding consumables, diff fluid & gasket, food to power me, and the opportunity cost of missing out on whatever else I'd be doing which is probably an opportunity gained since what else could be as productive as welding my own diff?

Thoughts are welcome.

[chesticals]

I have my diff welded on my e36 325, its kind of a neusince for daily driving, it makes the car sound and feel broken during any low speed turning. Gets alot of weird looks in parking lots. But an absolute dream for drifting. Cost me like 40 bucks, and now i have complete control of my angle with no guess work. Doesnt really get any more consistant than welded diff.

[iminhell1]

Originally Posted by The Wind Breezes

Maybe I'm on crack here, but a thought just occurred to me:

Normally for track use I'm in favor of having a really high lockup on acceleration for solid manipulation under power, and a really low lockup (open diff) under braking for stability and turn in. In other words, a 1 way LSD.

But, 1 ways aren't as good for drifting, and I've become more interested in drifting lately. So, why not just weld my diff? I'm aware that this will, with all other things being equal, increase understeer on turn-in and oversteer at the limit. More importantly, it may bring some issues if I need to maneuver the car in a tight space. We'll see, they're not supposed to be as bad for that as a welded front diff. I do drive the car every day, but it is not my only means of transportation.

A big factor here is I can pull the diff, weld it, and reinstall it all for the cost of electricity, welding consumables, diff fluid & gasket, food to power me, and the opportunity cost of missing out on whatever else I'd be doing which is probably an opportunity gained since what else could be as productive as welding my own diff?

Thoughts are welcome.

Those are 2 large reasons not to do this. A third is the cost to undue if you don't like it.
Something purpose built and not primarily a street car, go ahead and weld the diff. For a street car it's not a good idea.

[The Wind Breezes]

Originally Posted by iminhell1

For a street car it's not a good idea.

Please share your experience as to why this is the case. I'm planning on picking up another diff core from classifieds since once my core is welded, there's no turning back.

I don't really daily the car in the sense that most people are forced to--the car is more of a toy than an appliance to me. I do drive it to my office but I'm always hooning it around and typically enjoy most of my driving after 3 AM when the drunks have gotten home and the streets are empty.

[Esteban]

Originally Posted by The Wind Breezes

I don't really daily the car in the sense that most people are forced to--the car is more of a toy than an appliance to me. I do drive it to my office but I'm always hooning it around and typically enjoy most of my driving after 3 AM when the drunks have gotten home and the streets are empty.

I do a lot of my driving in the wee hours of the morning as well. Streets all to myself. Very enjoyable!

[The Wind Breezes]

Originally Posted by Esteban

I do a lot of my driving in the wee hours of the morning as well. Streets all to myself. Very enjoyable!

Absolutely! If you're gonna enjoy a car on the street, early morning is the time to do it .

Keep the comments coming. I'd be especially interested to hear from someone crazy enough to weld a late model BMW diff instead of buying a LSD.

[Solo_M_Tech]

Aside from accelerating rear tire wear and the annoying chirping when making turns, it's a cheap, easy way to have 100% lock up. The hard part is getting the gears clean enough for the welds to penetrate enough without contamination. Gear lubricant soaks into the pours of the steel, and when you weld on it, the oil is forced out of the pours, and contaminates the weld, making it weak. Worst case scenario, the welds fail and you grenade the diff. Best case, the welds hold, and you have to replace the rear tires all the time.

I say go for it. You'll have a back up diff just in case it goes wrong.

[The Wind Breezes]

Originally Posted by Uber///Madd

The hard part is getting the gears clean enough for the welds to penetrate enough without contamination. Gear lubricant soaks into the pours of the steel, and when you weld on it, the oil is forced out of the pours, and contaminates the weld, making it weak.

Oh, absolutely. I taught myself TIG starting in September and clean metal is probably the most important thing you can have. I'll be tigging the diff and will clean the gears including preheat with post cleaning. That way hopefully I can get almost all the oil out like you're talking about before I weld.

Also, USS MoneyPit. That's funny . Are you in the Navy or is that just your car?

[Solo_M_Tech]

Originally Posted by The Wind Breezes

Oh, absolutely. I taught myself TIG starting in September and clean metal is probably the most important thing you can have. I'll be tigging the diff and will clean the gears including preheat with post cleaning. That way hopefully I can get almost all the oil out like you're talking about before I weld.

Also, USS MoneyPit. That's funny . Are you in the Navy or is that just your car?

Bacon Potato Rocket is my car

[The Wind Breezes]

To update this thread, I drove a welded diff (100% accel / decel lockup) in Assetto Corsa in a simulated e36 325. For controls I have a T500RS.

Well, the results are in and IT IS NOTHING I WANT ANY PART OF IN A STREET CAR. The steering is heavy, car wants to drag on turn in, but that's not the main problem... Main issue is the car is always trying to bust out, not just into a little rotation, but full on oversteer. I have some experience drifting but that is NOTHING I want to deal with on the street, at high speeds. I would either have to stop driving fast, or be cool with some really hairy-ass behavior from the car.

Yes, it's a simulator, but the behavior is pretty spot on with what I've heard and there's no getting around it unless you drive slow--and even then you'll still need to slide.

New plan is to get an M-Factory metal plate clutch--one way, like I should have looked into from the start.

[ShocknAwe]

Glad you came to your senses OP.

[The Wind Breezes]

OK, admins forced a 2 month vacation on me, now I'm back with some updated info for this thread. Like, I decided to weld the diff after all and just finished this afternoon

Will stuff it back in the car and report on the handling characteristics, for better or for worse. It wasn't very easy to weld due to cleaning / position and I contaminated my tungsten like 10 times.

[YearOneOne]

This is great hahaha. Can't wait to hear the results

[The Wind Breezes]

Here's my welds, they're pretty bad but in my defense it was extremely difficult to position things because I had to hold the torch funny the entire time and stick the tungsten out pretty far. Ahh whatever, please laugh.

View post on imgur.com

Reasons I decided to weld the diff:

0) No money for a real diff
1) I put in a bunch of time drifting the locked diff cars in AC and it's easy now
2) I put in a bunch of time drifting in real life, feel much more confident, thoroughly hate theh e-diff and would LOVE to have a rear end that works like in the drift cars in the game. Yes they're setup with massive steering angle but the rear feels sooo good even with minimal angle.

[The Wind Breezes]

OK I put the diff back in and took the car for a quick spin. Here are my initial impressions:

--low speed stuff isn't a big deal at all, the welded diff doesn't really make the wheel any harder to turn or affect parking lot handling, just makes noise and presumably wears the tires
--some additional understeer, can be driven around 100%
--high speed cornering is massively different, huge response on throttle even in 3rd / 4th which is awesome
--needs more juice to take off with wheels turned so I will keep that in mind and make quick takeoffs to get the dct clutches locked fast so as not to overheat them
--1st / 2nd gear powerslides are extremely easy, predictable and consistent compared to the e-diff

I need to put the exhaust back on so this thing isn't a cop magnet then I'll hit up some parking lots and see how it drifts. It might rain later and I'm extremely excited to see how this thing handles the rain. I'm expecting slide after slide.

[Ginger_Extract]

Good luck with the welded. In theory, it's the same as a 2-way diff. We use one on our Project Craigslist Drift 240 and it does have compromises but for $30, it does make the car much easier to slide. We will actually be taking the hunt of junk to a road course at the end of the year and seeing how it works in that arena. It's much less forgiving than an open diff, obviously, but once you're used to it, it makes the car feel and handle more like a kart.
For DD purposes, yes, it will kill your rear tires quickly and cause more low speed drag, but I'd imagine even a stock 1'er has enough torque to make it negligible.

[The Wind Breezes]

Originally Posted by Ginger_Extract

Good luck with the welded.

Thank you!

Originally Posted by Ginger_Extract

In theory, it's the same as a 2-way diff.

Yes, if your 2 way was adjusted for a 100% torque bias (do people ever do this or do they just run a spool at that point?). 2 way diffs usually are setup with a torque bias less than 100, sometimes a lot less, meaning they start slipping after the % torque to one wheel exceeds the bias and are not be able to deliver all torque (no more than the bias amount) to the drive wheel. In a welded diff 100% of the drive torque is always available to the outside wheel and that's responsible for the lovely, lovely, razer sharp throttle steering, which makes the car >100% more exciting to drive.

[The Wind Breezes]

Small update, still rocking the diff, love the dynamics, and haven't broken anything yet. I do have horrendous wheel hop when spinning or sliding in the wet but in the dry it's not a problem. Gonna lock down my diff with a bracket and see if that helps...

[VazzVenom]

Post some drift videos.

[The Wind Breezes]

Well I just got a hero5 black and a hero5 session so hopefully I can hit the drift strip soon

[NinjaDog]

This is awesome. I was gonna blow like $4k on an LSD, now I'm just gonna weld it.

Cheers

[Gangplank]

I got my diff lockdown bracket from a member here in the classifieds. 135droptop I believe was the name. Good quality & quick shipping.