does upgrade to 12 inch clutch require different flywheel?

[Shadetreemechanic]

MY 87 with a t-19 needs a clutch. The roasted one I pulled yesterday is a made in Taiwan 11 inch disc.
Online I see lots of links for a 12 inch upgrade but its not clear whether I need a different flywheel.
The flywheel I removed seems like it could accommodate a 12 inch disc with the correct pressure plate.
Anyone done that upgrade?

 

[Macrobb]

Look up the LuK 07-065 cluch kit. Looks like it uses the stock flywheel?

 

[DaveBen]

Yes they all use the original flywheel.

 

[79jasper]

It seems people believe you lose some clamping pressure by going to the larger disc.
I don't know. No opinion.

Sent from my SM-G892A using Tapatalk

 

[Macrobb]

Clamping pressure... probably. My 07-225(12.3") is a lot easier to depress(so lower clamping pressure?) Than the old valeo dmf, but I know these things will hold a lot of torque. No problems dumping the clutch in my '93, and that has more hp and torque than most.
My thought is if it holds, no need to worry about how.

 

[Thewespaul]

The physical clamping force is less but it will hold more torque because of the increased surface area

 

[Shadetreemechanic]

The physical clamping force is less but it will hold more torque because of the increased surface area

What he said. I have two trucks with the 12 and they have always had better clutches than the 87.
The 87 would get hot at the drop of a hat when loaded.
Thanks for the confirmation on the flywheel. Now I need to track down someone to resurface it.

 

[shawn deere]

Ive got the stage 3 south bend clutch. 3.55 gears i think the tires are 33” or 34” now. Haul heavy at times (25k#). Havnt slipped it once. Even got stuck in some sand empty, revved up dumped clutch, killed engine. Twice. It wasnt smart, was a matter of pride after the first go. Ended up putting in 4 low to crawl out...

Its a good stiff pedal. They claim 20-25% stiffer and it seems like it. Has smooth engagement. Im impressed, had it about 8 months now

 

[Shadetreemechanic]

Just checked out the website and they don't seem to offer anything for the t-19. The shaft spline count is different from the zf-5

 

[Garbage_Mechan]

There is definitely a 12" clutch for the stock 6.9 flywheel I have had 2 trucks with them, one was a F350 with toilet pumper rig overloaded every day. Much better than 11". The hat has the same bolt pattern as the 11" the bolts are kind of "crowded" in.
I see no need for a "stiffer" clutch. Oh the 12" is a lever type (Borg and Beck?) FYI

 

[Shadetreemechanic]

I ordered a 12" luk. Should be here by the end of the week.