Clutchnet Vs. Spec

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ericjon262
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Clutchnet Vs. Spec

Post by ericjon262 »

I'm looking at two clutches for my 3500 F23 fiero, a clutchnet stage 3 or a spec stage 3. anyone have any real world experience with either clutch?
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Series8217
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Re: Clutchnet Vs. Spec

Post by Series8217 »

I have experience with multiple clutches from both vendors. I thought I had a comparison thread on here somewhere but I'm not sure where it went. Did you do a search?

Some info:
Clutchnet Dual Friction
http://realfierotech.com/phpBB/viewtopi ... =3&t=17112

The Clutchnet disc looks much sturdier and well built than the Spec disc. However, it's also a lot heavier, so it'll slow down your shifts. If you're not shifting above 6000 it's probably not a big deal.

I really liked the Spec Stage 2 for its infinite durability and lifespan. I ruined two of them due to transmission fluid leaks when my Getrag's detent housing cover popped off a few times though.

Make sure you get the correct pressure plate from the clutch vendor. The clutches vary in thickness from the stock clutch so you can't always mix and match plates.
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Re: Clutchnet Vs. Spec

Post by The Dark Side of Will »

My spec stage 3 holds ~300 WTQ just fine and can take abuse at that level. The CenterFarce was marginal with 265 WTQ.

I experience significant clutch chatter with it, HOWEVER, I have springy urethane powertrain mounts in a 4 point configuration on the cradle and no top-side torque strut. I'm hoping that the clutch chatter lessens or goes away when I get a torque strut installed.
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Re: Clutchnet Vs. Spec

Post by crzyone »

My Spec stage 3 chattered badly as well. I've heard it from a few people, might just be the clutch.
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Series8217
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Re: Clutchnet Vs. Spec

Post by Series8217 »

My Spec Stage 3 also chattered horribly, and when I pulled it out it clearly had not broken in properly. It was only wearing in a few thin lines.
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Re: Clutchnet Vs. Spec

Post by fieroguru »

I have ran a Spec Stage 2+, Stage 3, and several Stage 3+'s. Stage 3+ is the only one I will ever buy again (or the Stage 4+ which is a Stage 3+ w/o hub springs).
The stage 2+ is Stage 2 (kevlar) on one side, Stage 3 six puck on the other - would not hold the torque of the SBC (317 wtq)
Spec Stage 3 chattered like craxy, but it held the power... never got better after 7K+ miles.
Spec Stage 3+ was smooth from the start and held the power. It is a round solid face vs. 6 puck but with the same friction material. The stage 4+ is the same clutch, but w/o the hub springs.

Most negatives with Spec were the early runs having the hubs on backwards and then some people having issues with the hub springs popping out.

The SBC swap I am working on now the customer is supplying a Clutchnet 6 puck clutch. He said the old one chattered and was on/off switch, so we will see how the new one is...

My LS4 is 4 corner rubber mounted (no dog bone) and used the Spec Stage 4+ (10" diameter) clutch and it has good holding power (325 wtq, 3K launches in 2nd gear) and very nice street manners. I can inch it forward smoothly, pull into and out of parking spaces with ease, and take off from a stop shudder free.
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Re: Clutchnet Vs. Spec

Post by The Dark Side of Will »

Powertrain mounts affect clutch chatter significantly.
My Formula still has the stock 2.8 powertrain. I replaced the clutch with a stock replacement shortly after I bought the car in '06. That clutch has always been smooth. It's a stock clutch; it should be.
Earlier this year I switched from stock rubber mounts to Rodney Dickman urethane mounts with stock rubber dogbone. The clutch that hasn't given any problems for seven years suddenly chatters SEVERELY... I'm going to install a rod-end dogbone to see if that helps.
ericjon262
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Re: Clutchnet Vs. Spec

Post by ericjon262 »

Series8217 wrote:I have experience with multiple clutches from both vendors. I thought I had a comparison thread on here somewhere but I'm not sure where it went. Did you do a search?

Some info:
Clutchnet Dual Friction
http://realfierotech.com/phpBB/viewtopi ... =3&t=17112

The Clutchnet disc looks much sturdier and well built than the Spec disc. However, it's also a lot heavier, so it'll slow down your shifts. If you're not shifting above 6000 it's probably not a big deal.

I really liked the Spec Stage 2 for its infinite durability and lifespan. I ruined two of them due to transmission fluid leaks when my Getrag's detent housing cover popped off a few times though.

Make sure you get the correct pressure plate from the clutch vendor. The clutches vary in thickness from the stock clutch so you can't always mix and match plates.
I actually didn't do a search, I should have, and normally do.

as far as pressure plates go, I was going to buy the clutch and PP as a matched set.

you bring up a good point though about the weight of the clutch, something I hadn't really been considering. a lighter disc would do much better in the high RPM shifts, and be easier on the syncros. I would say the build is capable of 7500+ RPM, and if it's capable, I don't want to hinder it.
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Series8217
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Re: Clutchnet Vs. Spec

Post by Series8217 »

ericjon262 wrote: you bring up a good point though about the weight of the clutch, something I hadn't really been considering. a lighter disc would do much better in the high RPM shifts, and be easier on the syncros. I would say the build is capable of 7500+ RPM, and if it's capable, I don't want to hinder it.
My 282 doesn't like shifting above 6800 RPM or so. Not sure how much better the F23 is.

Does the F23 have enough bellhousing clearance to fit a twin-disc?
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Re: Clutchnet Vs. Spec

Post by The Dark Side of Will »

I've been shifting my 282 at 7k. It's slower than I'd like going into 2nd, even with the 3.50/2.19 combo, *but* I still have ATF in it and haven't swapped to Synchromesh yet.

A full face disk will result in slower shifts than a puck-type disk. A larger diameter disk will also shift more slowly than a smaller diameter. Remember, the force that operates the synchronizers comes from your arm, so your bicep/tricep is working directly against the heavier disk every time you shift.

I thought that the F23 had basically the same clutch space as the 282... so it should take a twin disk, although it will definitely be TIGHT.
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Re: Clutchnet Vs. Spec

Post by ericjon262 »

The Dark Side of Will wrote:I've been shifting my 282 at 7k. It's slower than I'd like going into 2nd, even with the 3.50/2.19 combo, *but* I still have ATF in it and haven't swapped to Synchromesh yet.

A full face disk will result in slower shifts than a puck-type disk. A larger diameter disk will also shift more slowly than a smaller diameter. Remember, the force that operates the synchronizers comes from your arm, so your bicep/tricep is working directly against the heavier disk every time you shift.

I thought that the F23 had basically the same clutch space as the 282... so it should take a twin disk, although it will definitely be TIGHT.
some 282 clutches fit the F23, some don't. I haven't really looked into a twin disc, ATM, I don't think it'd be in the budget. I still have to get the car close enough to me to be able to work on it again...
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Identity Crisis
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Re: Clutchnet Vs. Spec

Post by Identity Crisis »

What about BULLY Clutches? I used to be a seller of these clutches years ago and I had great service and support from them. Just throwing that out there. They made a special clutch for a 3800 L67 to an Izusu 5spd tranny years ago.

http://www.bullyclutch.com/
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Re: Clutchnet Vs. Spec

Post by Emc209i »

Hah... you beat me to the punch. I communicated many years ago with a guy on Club GP who has a built '01 Prix with the 3800 in it. He swapped a 284 and went the SPEC route to be disappointing like everyone else who does. He recommended Bully to me. Let me check Club GP and see if I still have the message.

----
Well I have his most recent post but not the older one. He used Bully and then Eurodrive.
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Euro-drive in Ontario, Canada. they are local and do numerous testing beyond any other clutch manufacture, they also make to suit your needs, my pressure plate is 3x stock, and they tested my spec pressure plate and it wasn't its 140% of the stock, which i believe was the problem with it.
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Re: Clutchnet Vs. Spec

Post by Series8217 »

Identity Crisis wrote:3800 L67 to an Izusu 5spd tranny years ago.
Wow, did second gear even last a week?
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Identity Crisis
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Re: Clutchnet Vs. Spec

Post by Identity Crisis »

Series8217 wrote:
Identity Crisis wrote:3800 L67 to an Izusu 5spd tranny years ago.
Wow, did second gear even last a week?
As far as I know the guy is still using it. But I have not talked to him since 03..... WOW ten years now.
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Re: Clutchnet Vs. Spec

Post by Shaun41178(2) »

gonna need something stronger than the spec 3+ since you are running boost. You are going to make big tq with a 3500 and boost on anything over 10 psi
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Re: Clutchnet Vs. Spec

Post by MstangsBware »

Dealing with CN now over them sending the wrong PP. Company has zero customer service and seems to send the wrong PP quite a bit. Will never buy from CN again.
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