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clutch for 400ish hp?

4x4man514

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Aug 28, 2003
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hey guys anyone got a favorite clutch for an engine making this kind of power? im not drag racing but i dont want something thats gonna be slipping all the time. plus id rather have something that drives smooth. i didnt think this would be an issue but the deeper i look the more i cant seem to find anything but a stock clutch. the motor is a stroked out 5.8 out of a 1990 f250. any suggestions?

thanks!
 

pcf_mark

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Jun 11, 2010
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3,574
I killed a few LuK clutches then switched to Spec and have had good luck. I have removed a failed centerforce but I do not know if it was user error or quality that killed it. I'm not a fan of the moving parts of a centerforce but the engineering is cool - OEM never used that design so I do not think it is a long life/reliability design. With Spec you get options based on power and how you use it.

https://specclutch.com/
 

DirtDonk

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One key factor in clutch performance and longevity, is how well your gear ratios play with your tire size.
If you have crappy gearing for your tire size you need a lot more clutch. If the gear is matched well, then it’s much easier to make a clutch perform better and last longer.

There haven’t been a lot of problems with Centerforce clutch us over the years, other than the occasional rattle that is annoying as hell. But I haven’t heard anyone complain of the rattling in probably 10 years or more.
Is that still a thing?

Luk makes the cores for Centerforce and probably others as well. Don’t know that they make all of them, but they make at least some of them.
We’ve had excellent luck with the Luk brand, but no way to tell how much power people tried to put in front of it, or what kind of gearing they put behind them.
 
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4x4man514

4x4man514

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Those spec clutches look interesting ill have to check into them further. Are they all more$$$$ than the rest?
 
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4x4man514

4x4man514

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Thats a good point about the gearing. Im running 37s with 456s so I would think it shouldn't be to much strain. This bronco prolly won't see much off road but 400ish hp might be rough on one
 

bmc69

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I've relied on Centerforce Dual Friction clutches in all my trucks, including the race truck that had a 486HP engine in it.
 

nvrstuk

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Just a Bronco driver for over 50 yrs!
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Most any organic disc and decent quality plate will work fine. 400 HP in reality is a low number in the HP world and there are a ton of imports running "tiny" (8.5" appr.) diameter clutches that have zero problems with 375-425+ HP meaning a good quality, low dollar disc/plate combo would give excellent "feathering"/driveability benefits and last for 100K miles with good gearing and proper use.

Buy a "racing type" clutch and you instantly run into problems for a DD moving a 4500+ # vehicle with 37" tires and what kind of trans....... ??? How come your sig line says you have a TH400??? lol

Anyway, got distracted when I read the TH400... :) difference between some fancy aftermarket "race style" clutch is they are designed to grab and hold. OE style clutches are designed to allow you to engage the clutch slowly without chatter and then "hold".

Something that's proven over and over like the CenterForce works for many.
 
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blubuckaroo

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Ridgefield WA
I've really enjoyed my Centerforce 2. It's got a nice pedal, but it is a bit abrupt on engagement.
I've heard that the Centerforce dual friction was designed to have a softer engagement by slipping a bit on engagement.
 

Broncobowsher

Total hack
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Jun 4, 2002
Messages
34,835
I remember watching people wheel a stock 3-speed and 3.50 gears on 33s. Lunch break involved adjusting the clutch because they wore it that much in just the morning and needed an adjustment to get through the afternoon. Not that it was a bad clutch, it was just poor gearing that required clutch abuse.
 
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4x4man514

4x4man514

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Most any organic disc and decent quality plate will work fine. 400 HP in reality is a low number in the HP world and there are a ton of imports running "tiny" (8.5" appr.) diameter clutches that have zero problems with 375-425+ HP meaning a good quality, low dollar disc/plate combo would give excellent "feathering"/driveability benefits and last for 100K miles with good gearing and proper use.

Buy a "racing type" clutch and you instantly run into problems for a DD moving a 4500+ # vehicle with 37" tires and what kind of trans....... ??? How come your sig line says you have a TH400??? lol

Anyway, got distracted when I read the TH400... :) difference between some fancy aftermarket "race style" clutch is they are designed to grab and hold. OE style clutches are designed to allow you to engage the clutch slowly without chatter and then "hold".

Something that's proven over and over like the CenterForce works for many.
oh yea i know 400 aint much . anything ive ever owned with alot of power had an auto.(hence the f150 with the big block and th400) i just didnt want anything to slip alot.

i have a 99 dually with a chipped 7.3 and a 6spd. it has gone through several clutches. always slipping. so i put one of those hi dollar strong clutches and all it did was make my left leg giant. hard to drive and it still slipped. so i finally went back to a stock clutch and just had to accept the fact i had to be easy with it.

this is what i want to avoid with my bronco. like i said no hard core wheeling. iwas want it to drive well without slipping when i get in the throttle

and my bronco has a zf 5spd in it. smooth as silk behind the wore out 302. i would like it to be the same with the 393 but just wasnt sure if that balance was possible
 
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4x4man514

4x4man514

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I've really enjoyed my Centerforce 2. It's got a nice pedal, but it is a bit abrupt on engagement.
I've heard that the Centerforce dual friction was designed to have a softer engagement by slipping a bit on engagement.
thanks. thats something for me to remember
 

nvrstuk

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Just a Bronco driver for over 50 yrs!
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ZF with a stock OE clutch would be perfect with the 400hp stroker you have.

There is no possible way (unless the clutch is adjusted wrong) that 400- 500HP will make a clutch slip cruising down the road in your Bronco. Ain't happening.
That said, if it's abused by slipping at high speed to get more rpms then yes, you'll smoke it. (Had a local buddy doing that and it didn't take long).

Engage the clutch and go. With the low 1st gear in the ZF you are not going to be slipping a clutch since you said earlier it's a light wheeler (if at all).

I ran a ZF for almost 20 yrs with a doubler and a stock OE clutch behind a healthy 351W. Not one issue with the clutch AFTER I learned the differences between friction surfaces on the discs and why you don't want a high perf style disc for a DD. This was back in the mid 80's. Summit returned 3 discs... :)
 

pcf_mark

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Jun 11, 2010
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LuK has a huge OEM business they make quality stuff. I just make more power than they can tolerate in some applications. In a 5.0 Mustang a step up from a stock clutch behind a cam/head engine making 400 hp will last forever. Gearing and weight in our trucks plays havoc on the clutch so I would rather go big than take it out to replace. I would call a few tech lines they are really good. You can easily over clutch and get high pedal effort or get a better design that can handle the power w/o a crappy feel. Clamping force helps hold but good material design is equally important. The marcel spring (thin wafer like spring) between the front and real has the biggest impact on engagement.
 
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4x4man514

4x4man514

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ZF with a stock OE clutch would be perfect with the 400hp stroker you have.

There is no possible way (unless the clutch is adjusted wrong) that 400- 500HP will make a clutch slip cruising down the road in your Bronco. Ain't happening.
That said, if it's abused by slipping at high speed to get more rpms then yes, you'll smoke it. (Had a local buddy doing that and it didn't take long).

Engage the clutch and go. With the low 1st gear in the ZF you are not going to be slipping a clutch since you said earlier it's a light wheeler (if at all).

I ran a ZF for almost 20 yrs with a doubler and a stock OE clutch behind a healthy 351W. Not one issue with the clutch AFTER I learned the differences between friction surfaces on the discs and why you don't want a high perf style disc for a DD. This was back in the mid 80's. Summit returned 3 discs... :)
so by "slipping " the clutch, do you mean he was riding it? why would anyone try to do that?

and youre right i def want this to be a easy driving dd.
 
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