3.4 DOHC clutch kit replacement (Page 1/3)
svocal SEP 27, 02:42 AM
I need your expert knowledge once again.
I have a 85 4 speed with a 3.4 DOCH swap in it.
What brand/type of clutch kit(disk, pressure plate, bearings, etc) do I need in order to replace it.?
I assume it isnt the stock 2.8 clutch kit.
Your feedback is most appreciated.
Dennis LaGrua SEP 27, 07:35 AM

quote
Originally posted by svocal:

I need your expert knowledge once again.
I have a 85 4 speed with a 3.4 DOCH swap in it.
What brand/type of clutch kit(disk, pressure plate, bearings, etc) do I need in order to replace it.?
I assume it isnt the stock 2.8 clutch kit.
Your feedback is most appreciated.


Most guys with basic manual swaps seem to be using the Spec Stage 3 clutch assembly. Your engine is putting out 215 HP so you should be OK with that .

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pmbrunelle SEP 27, 12:44 PM

quote
Originally posted by Dennis LaGrua:

Most guys with basic manual swaps seem to be using the Spec Stage 3 clutch assembly. Your engine is putting out 215 HP so you should be OK with that .




It's the 3+ that many folks are using, which is different from the 3 without the plus.

The Fiero Store Ram HD 9.75" is probably enough for 220-ish lb*ft of torque, and it's a bunch less costly.

I had the Ram clutch on my Fiero, and I found that the slippability / pedal effort was like any normal car. I would recommend it.

The only reason I got rid of the Ram was that it was slipping at WOT on my Fiero, but that was with more torque than 220 lb*ft.
svocal SEP 27, 02:24 PM
Thank Dennis LaGrua and PMBrunelle for your input.
Both of you mentioned the Spec Stage 3 clutch. What is difference between the Stage 3 and the Stage 3 + ?
My clutch appears to be slipping so I am having the mechanic replace it. My mechanic is not a Fiero Guru but he did ask to get the correct clutch kit so he could install it.
Since he will be replacing it, what other items should I replace while he is doing doing this? Do I need to replace the Pilot bushing and Release bearing as well? How do I know if they need replacement?

Thanks
Raydar SEP 27, 05:31 PM
I also would recommend the Ram clutch.
If you want to order it directly from Ram or Summit or Jegs, it's probably a lot cheaper.

I have one of those bolted to my 4.9. It's only about 220 HP, but it's probably in excess of 300 lb.ft. Works just fine.

Spec? I had a Spec 2 bolted to a 3.4 pushrod. I hated it. The 3+ may be a different story, but it's also expensive.

Edit - If you have a 4 speed (I missed that the first time), you will need a different kit. I don't know the Ram part #.
But Fiero Store has it here.
https://www.fierostore.com/...spx?s=54005&d=79&p=1

[This message has been edited by Raydar (edited 09-27-2021).]

svocal SEP 27, 05:46 PM
Thank you Raydar for your quick response.
In your experience with the spec vs RAM, what was it about the spec 2 you didn't like?
I have no idea what clutch is in my car. The previous owner had it installed,
I hear a lot about the Spec stage 3 clutches and the 3+. May others in the forum can chime in?
Difference between the Spec 2 and 3?
I just need a good reliable clutch that can compliment the 3.4 DOHC.

Thanks for the info
Raydar SEP 27, 05:54 PM
I edited my post. I didn't realize you had a 4 speed. It's a different clutch.
My Spec 2 (not a 2+) would chatter when it was cold, and would slip when it was hot. I hated it.
I have had two Ram clutches. (The 2nd one was due to an application problem on my part. The clutch itself was great!)
As mentioned before, it uses an organic lining. If acts just like a stock clutch, but has a much greater surface area. Since the DOHC is not known as a torque monster, you should be okay.
I'm about to swap a 3.4 DOHC, and will likely use my original Ram clutch, that I still have, if it will work with the F23 that I'm using.
svocal SEP 27, 06:05 PM
Raydar
Thanks for the follow up info. Much appreciated. It looks like the RAM clutch just might do the job. Going to wait for the other members to give me info on the spec stage 3 or 3+.
Then I will decide, but good to know the RAM will do just fine.
pmbrunelle SEP 27, 08:10 PM

quote
Originally posted by Raydar:
I have one of those bolted to my 4.9. It's only about 220 HP, but it's probably in excess of 300 lb.ft. Works just fine.



My Ram clutch (for the Muncie 4-speed) was definitely slipping with [benchracing] 318 lb*ft. I then detuned the engine to [benchracing] 291 lb*ft, and the slipping was almost all gone, with just a hair of occasional slippage.

The torque capacity might not be identical for all users.

Also, I don't think that I broke-in my Ram clutch properly.


After 12000 km of mixed-use driving (cruising, city, highway, dragstrip), the "Valeo" writing was still visible on the clutch disk friction face. Maybe with a better break-in I would have had better results, but I thought that 12000 km would have been enough.

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quote
Originally posted by svocal:
Going to wait for the other members to give me info on the spec stage 3 or 3+.



The 3 is a puck-type clutch; people say it will chatter.

The 3+ has a full-face disk. I have not tried it, but people say that it drives nicely. I have one on my engine, but it is not back in the car yet.

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quote
Originally posted by svocal:
what other items should I replace while he is doing doing this? Do I need to replace the Pilot bushing and Release bearing as well?



Fiero transmissions don't use pilot bearings.

The release bearing should be included in the clutch kit, along with the installation tool. This was true of the Ram and the Spec 3+ clutch kits that I received.

Optionally, if you want to replace the clutch release fork shaft bushings:
https://www.fierostore.com/...spx?s=54026&d=85&p=1

Seal that is removed/likely destroyed when you replace the bushings:
https://www.fierostore.com/...spx?s=54022&d=85&p=1

Rodney Dickman tool for bushing replacement:
https://rodneydickman.com/p...o.php?products_id=64
svocal SEP 28, 06:11 PM
PMBrunelle,
Thank you very much for your reply and input. Much Appreciated.
One more question.
Regardless of the clutch kit that i will purchase, do i need to change out the flywheel?

Stephen