West Coast Fiero dual clutch setup

Real tech discussion on design, fabrication, testing, development of custom or adapted parts for Pontiac Fieros. Not questions about the power a CAI will give.

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Shaun41178(2)
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West Coast Fiero dual clutch setup

Post by Shaun41178(2) »

Thoughts?

Maybe one for a getrag? No I didn't inquire. Steven?

They obviously offer one for the F23 for those that have made that swap.

http://westcoastfiero.com/products/dual ... ansmission
ericjon262
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Re: West Coast Fiero dual clutch setup

Post by ericjon262 »

one of the options is "stock fiero trans" from what I remember getrag clutches fit muncie's and izuzu's, but muncie clutches hit the case on the getrag, but don't quote me on that. I'd be interested to see how a twin disk like that feels, it should obviously hold very well.
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Series8217
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Re: West Coast Fiero dual clutch setup

Post by Series8217 »

It's hard to package a multi-disc clutch in a Getrag 282 because of clearance issues with case ribs and I think a shaft bearing boss.

I've driven Chris West's Aurora 4.0L Turbo Fiero which has a 7.25" Tilton dual-disc and NSX transmission. It's driveable but you can't slip the clutch without overheating and warping the floater plates, so stop and go traffic would be a bitch -- you'd have to leave a big gap so you can crawl in 1st gear with the clutch fully engaged. There just isn't enough mass or metal thickness to allow for much heat.

The 9.75" dual disc would be far more streetable than the little Tilton, but it would be quite a feat of packaging to fit one in a 282. Not really sure what the deal is with this one.
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Series8217
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Re: West Coast Fiero dual clutch setup

Post by Series8217 »

I talked to Chris about this setup over the weekend. They do indeed make a large-diameter dual disc clutch that fits the Getrag 282. Seems like this might be a good match for something like an LS4.

The point at which you're making enough torque to need it is probably the point at which you're breaking diff housings off the 282 though!
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Re: West Coast Fiero dual clutch setup

Post by Shaun41178(2) »

would be interesting to see this.

Will, since its two full size clutch plates, I am guessing it would be harder to shift at high rpm since there is more mass there now?
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Re: West Coast Fiero dual clutch setup

Post by The Dark Side of Will »

A typical "large diameter" for a multi-disk clutch is 8.5". Some MFG's offer them in this size.

This topic talks about an 8.5" *TRIPLE* for LT1's & LT4's.

@$$uming equivalent construction (material, thickness, density), which is probably not a good assumption as the smaller diameter disks are also likely thinner, then the dual 8.5" should have significantly greater MOI than a 9.125" single.

9.125^2 = 83.266

8.5^2 * 2 = 144.5

So an 8.5" would have to be 83/144 = 0.58 times as thick as a 9.125" disk in order to have the same MOI. It's kind of tough to make a disk that thin with any appreciable service life.

Reference:
7.25^2 * 2 = 105.125

A 7.25" would only have to be 0.8 times as thick as a 9.125" disk in order to have equivalent MOI. This is very much doable.

With the disks having a higher MOI, the 8.5" will be harder to shift than a 9.125" single
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