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Location:
Adelaide
Registered:
May 2002
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AE86/Clubman Diff advice
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Tue, 16 December 2003 12:02
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Toymods forum whores  ,
I know what some of you are thinking and those of you thinking it can fuck right off 
As those who are members of the Rex_Kelway fan club (one member - ME) would know Rex is building a Clubman. As background its to be powered by a 20V and at the end of its development should be pushing 180 - 190 flywheel Hp and weighing about 600kg.
Given my plans you can assume that its time will be split evenly between fiesty road and track work.
Now ill get to the point.
The rear end was to be based on a S3 Mazda RX7 diff. But recent times have seen a Kouki disc brake diff made available. The unit is 100% rebuilt and comes with a pretty much new Cusco 1.5way.
The total cost is cheaper than the RX7 diff would cost to 'build' to the same standard.
My problem is though. Because the thing is so rare (read: bloody expensive to repair/replace) i need to be sure that it can handle itself properly when im wearing my lead boots. But as an upside it does have a spare axle. Then again if axles are a problem i could pay to have billets made to kill the problem once and for all.
Also in order to use it i'd need to cut the mounts off so essentially it would become a bare housing with fabricated mounts. Then if something does break, and it cant be fixed easily it becomes useless to most people and hence worth very little unless parted.
On the other hand i do like th idea of a complete Toyota driveline.
I suppose that many of the '86s in Japan live pretty hard lives so i cant see there being any strength issues.
What are peoples thoughts on my ramblings?
Rex
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Location:
Melbourne
Registered:
May 2002
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Re: AE86/Clubman Diff advice
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Tue, 16 December 2003 21:37
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rexy,
about 104 prb s2's were built with the ae86 diff in them, so they must be ok!!!
be careful fiting aftermarket lsd's into clubmans, as their genrally to harsh for a 600kg car ( i recently fitted a kaaz diff inot a prb & that worked quite well after i set it to 60% - kaaz is adjustable, no idea on the cusco)
anyway, good luck with your project - be aware you might have issues registering it though emissions wise!!!
T
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I supported Toymods
Location:
melbourne
Registered:
June 2002
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Re: AE86/Clubman Diff advice
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Tue, 16 December 2003 23:06
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why would you have to cut the mounts off? i suppose youd have to relocate the pivot points for proper anti squat and all that.
i at first glance there would not be much problem of strength in a way due to the reduced weight, but my physics tells me that it wont be any different at all, as the car will be accelerating hareder, and in F = MA, M will go down, but A will go up.
IMO the diff should hold up, id (rightly or wrongly) put that much through a stock oz spec diff
one thing i have thought about in regards to a clubman is the issue of unsprung weight, and live axles arent the lightest things out there.
i cant see it being very easy to rig up a de-dion tube system though, and not many IRS systems are all that crash hot. maybeye womething with double wishbones would be ok? i know bongo vans have this setup, but a 1 litre engine copuldnt make that much torque.
if you do go live axle, make sure you use a watts link in place of the panhard rod, just for wank factor!
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Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
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Re: AE86/Clubman Diff advice
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Tue, 16 December 2003 23:26
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| shinybluesteel wrote on Wed, 17 December 2003 10:06 |
and not many IRS systems are all that crash hot. maybeye womething with double wishbones would be ok?
if you do go live axle, make sure you use a watts link in place of the panhard rod, just for wank factor!
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riiiiight... you know what a clubman is right??
do you actually know why a watts linkage is used instead of a panhard rod??
as for the Rex_Kelway fanclub
any dif housing you mod will be useless to most (except similarly built clubmans, or ppl wanting to cut the mounts off again)
axles you can always get made, housings cn always be repaired, so it's just the centre that you need to worry about... (all depends how harsh you will be )
Cya, Stewart
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I supported Toymods
Location:
Perth, Western Australia
Registered:
December 2002
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Re: AE86/Clubman Diff advice
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Wed, 17 December 2003 00:06
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| shinybluesteel wrote on Wed, 17 December 2003 07:06 |
i cant see it being very easy to rig up a de-dion tube system though, and not many IRS systems are all that crash hot. maybeye womething with double wishbones would be ok? i know bongo vans have this setup, but a 1 litre engine copuldnt make that much torque.
if you do go live axle, make sure you use a watts link in place of the panhard rod, just for wank factor!
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Have you ever seen a De-dion setup go around a corner???!!!! I'd also propose a car attemting to weigh @600Kgs (I know of two clubmans built down to a 450Kg weight and they have nothing in them!)wouldn't want wank factor in it?!!!
As for the Rex Kelway Fan club, yep I'm a memeber too, good guy to deal with, and not afraid to freight parts or call for info!
Rex, what are the "specs" of the Mazda diff? IRS, axle size, availability, inherent weak points, ...?
Personally I'd be chasing the IRS - you're basically starting with a clean sheet of paper, so why start behing the eight ball with a live axle setup?
As I said in another thread or PM to you, the cheapest option to replace axles in an AE86 diff is cutting down and resplining a disc brake Falcon axle, and if you still decide to go live axle, I have an AE86 housing out the back of the shed that has already had all the mounts cut off it (was used for an old Corolla, so only has leaf spring mounts on it), if you want to start fresh? You'll end up spending the same amount of money in the end I feel, wether you modify the Kouki, modify the RX7, or start with my housing.
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Location:
Adelaide
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May 2002
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Re: AE86/Clubman Diff advice
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Wed, 17 December 2003 08:25
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The S3 RX7 is a live axle diff. And its already been stripped of its mounts. The weight is acceptable.
Theres a few reasons for my choice of live axle. One being that its only my first completely fabricated car so simplicity big plus untill i finish reading my suspension engineering textbooks. Another advantage is that it will always keep the wheels prtety much vertical. Live axle although more unsprung weight is usually comparatively light compared to all the IRS hardware.
Petty reasons i know but as i said it is my first car
Some preliminary ideas have been thrown around about the next project, stuff like EJ20-T and IRS but thats down the track a bit .
Yes unsprung weight in a car like this can be a killer, but thats one of the reasons i want to keep the axle as light as possible. Many people i know have even used B/W based Cortina axles and its not as bad as some think, depends a bit on springing.
I suppose that keeping the RX7 axle is a good idea to start with, i can always look at trying something alse later.
CLG is dead right about the wank factor, its wank co-efficeint will be less than 0.001% wank. Anything of any wank value (apart from me) has no place on/in it
As for emissions laws, SA still operates under 37-01 regarding ICV's and only because we were pushed into going that far in the first place. Yes 79-01 is coming in for ICV's eventually but that still seems like a while off. Because i had started the build a couple of months ago (with proof) TSA has stated that in the interest of fairness i will need only comply with the ADR's regarding ICV's in effect when i began.
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Location:
Newcastle
Registered:
April 2003
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Location:
Adelaide
Registered:
May 2002
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Banned user
Location:
ADELAIDE - The Drift City
Registered:
July 2002
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Re: AE86/Clubman Diff advice
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Wed, 17 December 2003 16:32
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having owned a few S3 rx7's i know a lot about their weak points, In open diff form they are very week in the planetry gear sections with a few mild 12A's managing to blow them up, i killed a few behind my worked 13B NA also.
once i had a 13b Turbo i then upgraded to a mazdaspeed LSD, i was never totally happy with the LSd also (no where near as good as a TRD, cusco or KAAZ unit) as it too was only a 2 pinion lsd and the preload wasnt that crash hot, I suppose that can be adjusted but i couldnt be arsed and i sold the car.
snap an axle and you will have a VERY hard time finding another one (finding a JDM sprinter axle is EASY) for under 300 PER axle...
wheel bearings are also shitful, not liking much sideloads, but that wouldnt be much of an issue in a 500 kg clubman i doubt. Rear brakes are very effective for what they are also.
I'd go the toyota unit EVERY TIME....
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I supported Toymods
Location:
melbourne.victoria.austra...
Registered:
June 2002
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Location:
Adelaide
Registered:
September 2003
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Re: AE86/Clubman Diff advice
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Wed, 17 December 2003 21:17
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Rex,
Here is another option for you.
I have a Series 3 RX7 diff (ex Select Maz race car) that is setup with floating hubs, and has slight negative camber.
One axle is a little cactus (splines have twisted a little) but there is a spare axle with it. I was originally going to fit it top my RX2 Club Car, but ran out of time and money.
It is sitting in the shed ready to go to a good home for bugger all. It has some small solid discs already mounted.
Let me know if you want more details - I'm after about $150
Cheers
Michael B
042 111 9249
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I supported Toymods
Location:
melbourne
Registered:
June 2002
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Re: AE86/Clubman Diff advice
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Thu, 18 December 2003 00:40
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whoa, been away for a while it seems.
olcorrolas, yes i do know what a clubman is and i do know why a watts links is used instead of a panhard rod, i am sure you do too to call me out, but i dont feel the need to explain it here.
on the topic of watts links, a some of the cars i have seen them on (falcons i think) have hem monted wrong, with the "chassis" link ends mounted at the same height, can you tell me why this is the wrong way to do it?
if i was custom building a live axle, i would definately use a watts link, i dont think it would add much unsprung weight, apart from the centre link really, and that wouldnt be heaps.
i still may even put one in my AE86 if it can be done easily.
and no, i have never seen a de-dion rear axled car go around a corner, from what i have heard they are a fairly good setup, im pretty sure the better fraser clubmans use them in place of the live axle.
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