I'm bouncing back and forth between putting another M46 in my 740 and babying things or building an adapter for my T5. One clutch option is to use the CF pressure plate, leaving a brand new unused Dual Friction clutch disc up for grabs (since Centerforce will not sell this part as a replacement, this might be attractive to some) and using the 2.3 litre Ford clutch disc instead. Another option is to use a Turbo Coupe / SVO clutch and redrill the flywheel, which would mean my entire CF clutch kit is available.

Anyone have any interest for either part? The whole clutch kit was $350, or I'd sell the pressure plate for $150.

Thoughts?

I don't know what you should do with your car, but if the "Centerforce Dual Friction 8.5" clutch" kit is a good replacement for stock clutch, then I will take it.

Won't work in your car, unless you machine a flywheel to suit it. Your car has the big heavy flywheel with holes to trigger the engine computer, and this clutch won't fit.

You could have your flywheel machined flat and drilled for this clutch, which would give you a nicer, more responsive engine, but that's for you to decide.

Oh...

I'll try to keep it simple.

Bump... from like 1 post down the page.

Its always important to have the top spot....its definately all I look at. Good luck Matt, heres a free bump for you to keep you on top.

Hey, Andy - while you're looking, what specification was your Clutchnet clutch?

what would you like to know?
clutchnet 8.5" carbon clutch (yellow) with a 22 spline sprung hub
yellow 8.5" pressure plate which is supposed to hold 25-55% more power


I was talking to James though and he blessed his wisdom upon me. Apparently a stock volvo clutch is .275 inches thick, whereas the clutchnet one is .325 inches thick....so this could be where my slipping was occuring in the beginning. Pretty much you have to machine a 50 thou step on your flywheel to run these correctly, or else you just get the pressure plate with the really high clamping force.

Exactly what I wanted to know.

I'm looking at that T5/Redblock/Flat flywheel clutch that's on Tbrix. It's a red pressure plate (100% increase) and a carbon fibre disc. Based on your experience I was skeptical, but after hearing this...

Is it hard to get? (a machined flywheel)

Just to clarify or muck this up as I often do , here are is what I observed:

A brand new stock volvo sachs disc for a 740 turbo is .275"
My fairly new sachs sport disc was ~.275" or so.
A brand new sachs made disc for a BMW diesel that was much the same design as my sachs sport was .325".
I couldn't get a super new 8.5" 240T to measure, but the one I measured was a bit under .270", leading me to believe that it was probably .275" thick new and it wasn't super worn out.
My clutchnet 8.5" kevlar disc is .325".

I took these measurements at mild clamping of the discs just so they'd lay flat with my less beateriffic calipers for most . Still, 50 thou is a TON in pressure plate terms.

I wish I had had all this data and homework done out the first time I threw the getrag in my 940. It would have saved me making a hash of my diesel disc, which probably would have behaved nicely like my sachs sport did. Instead, it slipped at about 5psi. I doubly wish that I'd seen Andy's earlier posts so I could have helped prevent making the same mistake I did. The pain wasn't so bad for me, since the getrag can be removed very quickly and easily and I paid a whopping 30 bones for a NOS diesel clutch.

I'll probably fit the 8.5" kevlar thing to the flat flywheel once I have a suitable pressure plate. I've had zero problems with the mild kevlar disc so far with the stock old tired sachs sport PP after grinding a 50 though step in the friction surface. It does chatter a bit cold, probably from me being ghetto and not replacing the PP and leaving the old clutch's wear pattern still on it.

Care to measure the CF disc if it is conveniently out of the packaging, Matt? Would you sell just the PP? As, even though I'm about to have an M47, I don't think I'll bother putting anything stronger than a turbo clutch in front of it.
EDIT:
I drove Poik's 744 once with the new clutchnet 4-puck in it on a stock PP. His grips really nice, I mean, the damn thing is a 4-puck thing! The clutch pedal feels notably wrong like it did in my car with the BMW disc, however. It feels uniformly light all over instead of the "ramp up and break through" feeling that you can feel even with a healthy stock PP. This leads me to believe that most clutchnet clutch discs are of different thickness than the stock volvo sachs applications.
Edit2: Sorry for mucking up a for sale thread with boring irrelevant info.
Whoo, way too many words for my own stupidity ,
-James

No problem with the verbal diharrhea, James. Thanks as always for the bounteous information!

I considered selling the disc as Centerforce doesn't offer them, and just using a 2.3 Mustang disc under that PP, but I'm worried about clamping. The CF PP doesn't have any stiffer springs, just those weights, and on our tractor motors I wonder how much force they add at 2500 RPM. If you want to buy just the PP I can see if someone wants the disc as a replacement.

Interesting:

The disc is about .325" thick. Naturally I thought it was the fault of the half that was added, so I measured the stock Fitchel & Sachs material: .130" thick. The F&S material plus the marcel disc is .205" thick. .205 + .130 = .335", which could presumably be the overall thickness of a new F&S disc. Of course, there's marcel error, the one side might be ground down to get a finished thickness of .325", and I'm even wondering if the Centerforce friction material is bonded to it's own marcel disc that gets rivited to the F&S marcel disc. I'll have a closer look at it tonight, as I was giving it a passing measurement this morning on my way to work.

Of course, there's always the possibility that the CF disc is a bit thicker than OEM because the PP is refurbished... If the PP has been resurfaced .050" a thicker disc would be needed to get the clamping force back. Ditto for the Clutchnet piece: after the doubly-thick spring is added, it'll push the PP hub closer to the flywheel, requiring either a thinner disc or a thinner PP surface.

Aaand a correction. Yes indeed, the "dual friction" part of the disc is indeed bonded to it's own backing plate. From the best measurement I can get, the F&S marcel disc is about .020" thick, making the overall OEM clutch thickness about .275-.280"

Very cool stuff Matt. Go ahead and sell the CF whole. My car will get a cheap ghetto clutch of some sort until I feel it needs more powar111