mx5cartalk.com

Hey guys


Coming from an import background, i have had diffs ranging from 2ways, shimmed lsds and lockers. From a drifting point of view, I found the locker/welded diff to be the strongest and most predictable diff type.

I know about the legalities of driving with a locked diff on the street along with all the other cons that come with it - tyre wear, driveline strain ect ect

Just wondering how many of you guys use welded diffs for both competition and daily driving use? Also how much punishment can the standard diff/axles take?

Just after a predictable diff setup without breaking the bank!

Thanks kindly in advance

Eddie

AFAIK, the serious and honest answer is none of us do.

Even Sheck who was drifting his MX5 in events was using a KAAZ I believe.......

The other reliable option is always a Guru, or a torsen. It just depends on what you want to do with it.

I can only assume from your user name you are talking about competition (drift) as opposed to track?

In terms of outcomes - remember the rule of three.

You can have it cheap, you can have it good, or you can have it now. Pick any two in combination but you usually can't have the third as well.

Just buy a spool.

Check Mania's site.

Nah the mx5 wont be drifted anytime soon, the reason why im bought a nb was for a whole different ball scene... no more drifting (for now)!


Correct me if I'm wrong, but isn't a full spool pretty much the same effect as welding?

dorifta wrote:Correct me if I'm wrong, but isn't a full spool pretty much the same effect as welding?

Same effect, (ie both wheels permanently locked together) though slightly different way of doing it.

A spool is made especially for the job, and can mean lighter internals (less power losses) as you can ditch the spider gears.
A 'CIG locker' is just using weld to restrict the spider gears from doing their job. The effectiveness of this method can vary enormously with welders skill level...

Having said that I ran a welded diff in my race car for 10 years without issue.

So what do you hope to achieve by having a locked diff? Then someone here will be able to tell you the better solution...

There is a CIG locker in my race car. There was a CIG locker in the MX5 Racing NC I drove at Oran Park. AFAIK almost ALL the NSW racers are using lockers - either spool or CIG. At the same time almost NONE of the QLD guys use lockers...

They are predictable, but I wouldn't put one in a car I built myself. I'd go for a clutch type.

Boags

Guru - ok on the street but destroyed in the race car
Spool - hated it
Currently use Cusco MZ 2 way LSD - Love it!
The other LSD equiped cars I know of use the Kaaz (similar to the Cusco and Tomei)
Torsen is OK on the street and is the regulated LSD for 2F in QLD.
1.8 axles start to break above 180+ rwkw -as will a stock 5 or 6 sp gearbox

How much are these full spools?


I had a 320hp hks2535 application in the rb25, in that time I had:

GTR diff welded - Fail - Just like you pointed out rascal... lets just say it was a mess!

Nismo 2 way with 4:11s - Started singling slightly, became too unpredictable.. cracked the shits and went back to a locker which till this day is still running strong.


Hows the whole short wheel base + push understeer thing work together on the people that run spools/CIG?

*WARNING* Anecdotal Evidence Follows!

I had a locked diff in a Datsun 240k and it pushed on turn in and it pushed out of the corner too. It was painful and I think I would have been quicker with an open diff.

The NA race car is no where near that bad - neither was the NC I drove. It turns in well (in the dry) and only steps out if I'm a little too keen on the throttle (ok, it leaves black lines unless you are VERY careful). In the wet the understeer was much more obvious.

Could this be because the wheelbase is shorter? I would have thought being lighter and shorter that the MX5 would push MORE. Might have more to do with suspension and tyres...

If you have a road car - do not even consider a locked diff. Get a clutch type or guru/torsen.

Boags wrote:I had a locked diff in a Datsun 240k and it pushed on turn in and it pushed out of the corner too. It was painful and I think I would have been quicker with an open diff.

If it was anything like my 240z, it would have pushed with an open diff as well. Fun to drive, but push understeer or power induced over steer Suspension geometry has come a long way.

I though the biggest problem with locked diffs on the street was snapped axles from the tight, slow cornering ie. through carparks. It twists the axle and it eventually breaks.

Spools are $695 if you get them from Mania (http://www.mx5mania.com.au/transmission.htm)

Boags wrote:I had a locked diff in a Datsun 240k and it pushed on turn in and it pushed out of the corner too. It was painful and I think I would have been quicker with an open diff.

By nature, all fully locked diffs will push more than open diffs. But it is also relatively easy to dial out the push with suspension adjustments.

In my case putting a welded diff in place of the open centre was the best thing I did for lap times in the old car..

Spools are illegal on the street. A decent Lsd is the best solution.

I've only ever seen welded diffs used on the dirt (speedway) On the road it would make any car handle bad and in the wet you would be sideways everywhere.
Welding a diff is not as easy as it sounds either, Have done a few for the speedway and found that they have to be machined so that when it's welded the axles are running true otherwise Kaboom