LSD

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racingem
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LSD

#1 Post by racingem » Tue Oct 17, 2017 5:38 pm

Hi. I have a 1981 rx7 series 2 and was wondering what options for a LSD ? Who sells them or does anyone have 1 or will later models fit? Thanks in advance. :D



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Re: LSD

#2 Post by RX7_BEN » Tue Oct 17, 2017 8:51 pm

You've got a choice between fuck all and expensive. Sorry to be the bearer of bad news.

You can try and hunt down a factory 24 spline LSD which they never sold here so they're impossible to find. Usually need to source from the states or Japan, or pay through the nose here if you're lucky enough to find one.

The other option which keeps the factory housing and axles is to go for a Modena Torsen LSD. I'm not sure if you can still get them, but getting in touch with Bill Schoots and WPS racing might yield some results and be expensive to boot. They were originally made by Rohan Ambrose of Xtreme Rotaries (Guru motorsports).

Another road you can head down, especially if you're pushing some power is to consider a diff conversion. This gets pretty expensive once you've factored in finding the appropriate gear ratio for your application, which center you wish to run, modifying brakes to work, having the diff housing modified to fit your car, custom watts link or panhard rod, perhaps adjustable trailing arms as well.
A lot of people choose the Hilux diff or Ford 9". I consider the 9" overkill for all applications that aren't drag racing. The Hilux seems to be a good compromise between size and strength with plenty of gear ratio and center availability. I would recommend looking at the Eaton TruTrac for the center of a Hilux diff for road use. Then the ratio depends on your intended application.

Hope that helps you mate.



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Re: LSD

#3 Post by racingem » Tue Oct 17, 2017 9:09 pm

Good information .Thanks. :bow:



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Re: LSD

#4 Post by Eeyore » Thu Oct 19, 2017 6:23 pm

I think a KAAZ 1.8 MX5 LSD can be made to fit but would probably require custom axels.


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Re: LSD

#5 Post by Slides » Mon Oct 23, 2017 1:37 pm

The early mx5 diff centres are bolt in to 26 spline s3 probably a lot of headaches trying to go in s2 as the bearing setup in axle tubes is different.

Talk to nvspasngr on here, he was rebuilding and selling s2 and s3 diff centres a while ago.



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Re: LSD

#6 Post by Schonza » Tue Oct 24, 2017 9:45 am

How much power you are going to have, and what you are using the car for well be the determining factor.

If you are running a N/A motor, your best bet is to source a series 3 rear end and find an appropriate LSD center. You have the choice of plate style LSD's such as the KAAZ, Cusco or OS Gilken, or a helical style LSD such as a torsen or Quaife.
If you are going anthing more than just a standard s4/s5 turbo motor, then as mentioned earlier your best option is a Hilux rear end. It is heavier than the s3 rear end as well so the extra weight may make a lightly ported motor seem sluggish.

I just converted the rear end of my series 2 to a series 3 with a type 2 torsen from an early mx-5. By the time I bought the rear end, diff centre, had the centre rebuilt and assembled, and paid someone to do the fiddly bits of changing the rear end (PCD change, rear brakes, handbrake adjustment) it has probably set me back around the $3000 mark. A Hilux conversion would be around the same price, maybe even more, but I'm sure someone could confirm that for me.



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Re: LSD

#7 Post by NAN445 » Tue Oct 24, 2017 12:58 pm

RX7_BEN wrote: A lot of people choose the Hilux diff or Ford 9". I consider the 9" overkill for all applications that aren't drag racing. The Hilux seems to be a good compromise between size and strength with plenty of gear ratio and center availability.
Can I ask what makes you consider the 9"to be overkill in applications other then drag racing mate..?

Hilux is definitely a good compromise, however getting decent axels can be an issue and/or expensive.


cpekel wrote:Punch that bitch in the cunt
Capella/RX-2 Parts For Sale >>> http://ausrotary.com/viewtopic.php?f=48&t=231954" onclick="window.open(this.href);return false;

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Re: LSD

#8 Post by RX7_BEN » Tue Oct 24, 2017 2:55 pm

NAN445 wrote:
RX7_BEN wrote: A lot of people choose the Hilux diff or Ford 9". I consider the 9" overkill for all applications that aren't drag racing. The Hilux seems to be a good compromise between size and strength with plenty of gear ratio and center availability.
Can I ask what makes you consider the 9"to be overkill in applications other then drag racing mate..?

Hilux is definitely a good compromise, however getting decent axels can be an issue and/or expensive.
Yeah, sure. There's a few reasons I consider that to be the case. One of which is the physical dimensions of the diffs. These are tiny cars we're talking about and the more compact the components that can be utilised, the better. The 9" can be made to weigh in the same ballpark as a Hilux diff so weight isn't necessarily a concern (although generally a 9" will be heavier), however why put something physically bigger than you need which you will never break without the shock loads of drag racing on slicks.

There's always exceptions to every rule, but 99% of old Mazdas will never ever break a Hilux diff when used for activities other than drag racing.

For example, why would you spring for a 9" when you've got 150hp? IMHO the smarter money would be in the Hilux which won't break, it offers a great range of ratios, plenty of options for different centers etc.

Like the vast majority, I don't think this fella is looking for something to suit a 1000hp application.

I suppose what it really boils down to is those insane shock loads that you get leaving the line in drag racing at big revs on sticky tyres that you won't find anywhere else. Make sense?



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Re: LSD

#9 Post by NAN445 » Tue Oct 24, 2017 4:48 pm

RX7_BEN wrote:
NAN445 wrote:
RX7_BEN wrote: A lot of people choose the Hilux diff or Ford 9". I consider the 9" overkill for all applications that aren't drag racing. The Hilux seems to be a good compromise between size and strength with plenty of gear ratio and center availability.
Can I ask what makes you consider the 9"to be overkill in applications other then drag racing mate..?

Hilux is definitely a good compromise, however getting decent axels can be an issue and/or expensive.
Yeah, sure. There's a few reasons I consider that to be the case. One of which is the physical dimensions of the diffs. These are tiny cars we're talking about and the more compact the components that can be utilised, the better. The 9" can be made to weigh in the same ballpark as a Hilux diff so weight isn't necessarily a concern (although generally a 9" will be heavier), however why put something physically bigger than you need which you will never break without the shock loads of drag racing on slicks.

There's always exceptions to every rule, but 99% of old Mazdas will never ever break a Hilux diff when used for activities other than drag racing.

For example, why would you spring for a 9" when you've got 150hp? IMHO the smarter money would be in the Hilux which won't break, it offers a great range of ratios, plenty of options for different centers etc.

Like the vast majority, I don't think this fella is looking for something to suit a 1000hp application.

I suppose what it really boils down to is those insane shock loads that you get leaving the line in drag racing at big revs on sticky tyres that you won't find anywhere else. Make sense?
All very valid points mate.

Reason I asked is I currently have a hilux in my Capella, but want to convert it to disc brake and shorten it to allow wheels with a deeper back spacing be used (all about the wank factor :gay: )

When speaking with my Fabricator on our best way to attack things, he suggested a 9"over another hilux (even though I already have a second housing to use) as cost and weight wise they work out to be similar (when built from scratch) with the 9" having easily double the range of parts and options to build to your exact requirements. He also mentioned finding axels to suit the hilux can be incredibly difficult, whereas the 9" has an endless range of options...

Still unsure which route we will take, but at this stage the 9" is looking to be the easiest and best option (for my requirements).


cpekel wrote:Punch that bitch in the cunt
Capella/RX-2 Parts For Sale >>> http://ausrotary.com/viewtopic.php?f=48&t=231954" onclick="window.open(this.href);return false;

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