Rear axle options

[Dino86]

I'm considering to upgrade my diff to shorter ratio and have more lock. Current I do not want to spend a lot of money on it.
Therefore I'm considering cheap solution:

Anyone knows of a 'plug and play' 'open diff' rear axle with shorter ratio than OE AE86 from another model? (5:1 something)
Than if it's cheap, I plan welding it and give it a try.

It will be for rally-use. Searching the www gave me different feedback on it so I assume it depends mostly on the driver how he handles the 100% lock. If it doesn't work I might put it up for sale for the drifters

[Project D]

There is literally nothing "bolt on" on the AE86 other than the OEM rear axle (S and T series) and none of them come with a shorter ratio than 4.3:1...
Oh and welded diff are absolutely awful, even for drifting. So I would definitely not recommend it for rally.

[Power_uP]

I would also advise against welding the diff, I once drove a Skyline with a welded diff and it certainly isn't the best choice.

Perhaps if you gave some idea of your budget people could give better advice.

[ditn]

well there is no cheap solution
i run quaife lsd with group4 english axle shafts and 5,1
bought from german Rally guru

[mad.matt]

I'll provide some counter advice.

Driving with welded diffs are fine.
NA6 Eunos Roadster 1.6 - Welded diff, never driven with one before. Just pushes front end wide unless on power. Decent front tyres and plenty of man foot is fine. Daily drove it for a year with a welded diff without any issues. Drifted it just fine too.

BMW E36 328 with a welded diff - Same again. Daily drove it for 9 months, no issues at all.

BUT - both these had IRS not a solid axle so I don't know how much difference that makes.

It is no substitute for a proper LSD as you don't get the benefit without the negatives - understeer at low speeds, tyre skipping/jumping on tight turns.

[totta Crolla]

A welded differential is great..... until you break a halfshaft and then it is an instant trip off road or into on-coming traffic !

[headrush]

It all depends on what you're used to, where you come from (experience with previous cars), or your expectations with the car. A welded diff would be great for some people, others will hate it. Expectations and needs may vary from one driver to another.

I rode shotgun on my friend's Ford Sierra with welded diff and while it's drivable in most scenarios and not as bad as some people say, I would not use it as a daily driver because of the (lack of) comfort on parking ramps and tight turns. Besides that, I would be affraid of screwing a half shaft all the time.

Now, for a weekend / fun / track / rally car I find it a cheap mod if 100% lock and throttle steering is your goal. As long as you always keep an spare diff and a couple of half shafts, just in case

[ditn]

i would never drive with a welded diff ...

[Deuce Cam]

Quote:It is no substitute for a proper LSD

Indeed

Quote:as you don't get the benefit without the negatives - understeer at low speeds, tyre skipping/jumping on tight turns.

Not exactly. With a proper after market clutch lsd one will still get some of these characteristics. They're usually set to 100% lockup default, and their engagement comes from throttle/engine load. Ae86 is an underpowered car so a reasonable amount of throttle is needed just to accelerate. This is compounded if the drivetrain is geared down because rpm will always be higher - at any road speed - compared to oem.

Fwiw Ive got a cusco rs 1.5. Had it 6 years and roughly 15k miles. Street car only. Still locks hard. Car understeers unless i completely let off throttle in a *really* tight bend, like a switch-back aka horseshoe turn. Theres an even more noticeable difference if the car is in neutral for a turn.

I occassionally still get tire skipping/jumping/chirping, but it was noticeably worse when lsd was new. However, i get the pogo'y unsettlrd feel in turns often, even when just driving a bit gingerly. Its the equal wheels speeds. It can be annoying, but is an expected characteristic of a mechanical/clutch lsd. Sometime i want to adjust my lsd to its minimal lockup setting (60%) by rearranging the plate. Since my lsd has springs between yhe gears and plates.... as i umderstand it some springs can be removed to soften the ramp rate, i.e. it takes more load to engage the lockup.

An aggressive lsd is best suited for a tail out driving style imo. Im not really trying to do drive lime that on public roads...

[Dino86]

Hi all,
happy new year at first !!!

Sorry for the late reply... was on holiday :-)
Most replies confirms what I found on the www already... there are many opinions.
Since only OEM diff can fit, probably finding a cheap one to weld (and maybe destroy...) is unlikely... For sure I agree it doesn't beat proper LSD anyway --> that's clear.

@Power_up: I expect cost around 1000-1200€ incl. installation and adjustment. So if needed I might spend it on the diff but it's not highest priority... therefore I wanted to check cheaper solution at first.
@Ditn: If you have another address where I could find similar setup as yours that would be great.... or sell me yours

Anyway more opinions/ideas are welcome.