Do I really need a fancy diff?

[JB21]

Just doing the normal Friday go faster bits search and started thinking about aftermarket diffs for the MR2 as I'm looking to enter the Javelin sprint series next year. Another reason is that this year at CSF19 I had a really good battle with a Javelin sprint series Clio 200 that was running a Gripper and although I was as quick over a lap, through Bunga, Bunga and Port Froid which are fast sweeping bends he just left me for dead. He said he could go flat through both since fitting the gripper diff, whereas I was having no choice but to lift quite a bit. Thing is I can see how that works in a FWD car but not sure in a RWD car it would be as beneficial, given RWD its being pushed versus being pulled like in a FWD layout. Or does a diff in RWD work just as well in these types of scenarios?

The car is actually running a factory Torsen LSD but in all honesty I've never really felt it doing its thing as i'm quite a smooth driver not often breaking traction on exit, which leads me onto 'do I need a fancy diff?' My car has very little torque and i'm not the type of driver to purposely hang the rear out on track as it just halts progress and increases risk of binning it in my opinion, so i'm not so sure my car would actually benefit from a fancy diff?

Now if you think my car would benefit, then what type of diff would be best? Gripper, Quaife, KAAZ? 1 way, 1.5 way, 2 way etc?

 

[andybond]

No, you dont need a gucci diff.

One is a FWD , Front engined car , the other a mid engined RWD car. They are dynamically about as polar opposite as you can get.

There are so many variables between the cars ( tyres, age of tyre , suspension health , suspension setup , geo ) that its hard to compare where you can , and cannot flat foot a set of bends.

 

[JB21]

No, you dont need a gucci diff.

One is a FWD , Front engined car , the other a mid engined RWD car. They are dynamically about as polar opposite as you can get.

There are so many variables between the cars ( tyres, age of tyre , suspension health , suspension setup , geo ) that its hard to compare where you can , and cannot flat foot a set of bends.

Think set up would be were it could be changed the most given mine is set up very safe with soft springs and Arbs set full soft and its also toeing in lots at the rear, so set up more towards understeer.

Once back together I'm going to set the toe parallel at the rear to see how it feels.

What alignment set up is yours running?

 

[andybond]

I am just about to change it actually as I have had the shocks rebuilt by Nitron and some new rear toe links added. Not 100% sure on the setup I am going to go for so going to take some advice on heights , angles etc from the experts.

 

[JamesBryan]

I would start at 1mm out on the front and 1mm in on the rear.

 

[JB21]

I am just about to change it actually as I have had the shocks rebuilt by Nitron and some new rear toe links added. Not 100% sure on the setup I am going to go for so going to take some advice on heights , angles etc from the experts.

Let us know what they reccomend. Although our cars have very different chassis and power the MR principle will be the same.

 

[JB21]

I would start at 1mm out on the front and 1mm in on the rear.

Cheers mate. Current set up is 1mm out total on the front and a whopping 5mm in total on the rear. As I said very safe.

 

[massiveCoRbyn]

I think I would look at other options first. If you already have a torsen diff, any benefits from a plate diff (which is the best for track use) are going to be limited compared to fitting one to a car with an open diff.

I'd make sure the springs/dampers/geo are all perfected first, then see how you feel.

 

[Kev@KAM]

I would expect the clio to have the legs on you regardless but it also helps he will power understeer when cocking up so its easier to get on the limit.
My AE86 has a 2 way plate diff. Its pretty awesome. Set up right its just as useful as a FWD car.
If you want a quote on a Kaaz or Quaife I can help.
Do you use the MR2 on the road? If so Kaaz do quiet versions of their diffs.

 

[JB21]

I would expect the clio to have the legs on you regardless but it also helps he will power understeer when cocking up so its easier to get on the limit.
My AE86 has a 2 way plate diff. Its pretty awesome. Set up right its just as useful as a FWD car.
If you want a quote on a Kaaz or Quaife I can help.
Do you use the MR2 on the road? If so Kaaz do quiet versions of their diffs.

Caught it pretty easily on the straights and under braking, just the fast sweeping corners where he made the time up.

Yeah been looking at the Kaaz 2 way but as it's used to commute to and from track it maybe to aggressive?

What sort of price are they out of interest? 2ZZ engine/C60 box.

 

[Kev@KAM]

£790 for standard, £819 for the SuperQ. From what I can see there is only a 1.5 way which should work well for what you need as its less aggressive on deceleration
I have a listing here

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