FYI for a centerforce DF 12" clutch. - Chevelle Tech
Performance Our High Performance area

 2Likes
Reply
 
LinkBack Thread Tools Search this Thread Display Modes
post #1 of 29 (permalink) Old Apr 26th, 17, 10:59 PM Thread Starter
Team Member
Geoff Swanson
 
Join Date: Feb 2015
Location: Tucson, AZ
Posts: 601
FYI for a centerforce DF 12" clutch.

Today I went out to my favorite test area, heated up the slicks and did a test launch. It slipped in first through second.
The engine is 650+ HP with torque somewhere in the same range. I'm being conservative as I have not had the car on the dyno yet with the new top end. The old top end made 529 RWHP which equates to 625 ish HP at the crank. This new set up pulls much harder and MPH is up 4-5MPH in the 1/4" even while smoking the clutch through 1st and 2nd and not getting into 4th until the 1000" + mark. With the old set up I was in 4th by the 800" mark.
The clutch has maybe 1000 miles with a hydraulic throw out bearing clearance of .100",was installed on a fresh cut flywheel and was broken in gently over a couple hundred mile. I looked for a possible oil leak getting in the BH but that was not happening either.
I had a pic from the drag stip 2 weeks ago which showed the clutch smoking bad at launch. Before posting I wanted to make sure everything was set correctly and verify what I saw in the pic. I would have posted the pic but I had posted it in another thread and evidently you can't post it twice.
I'm not here bashing CF as they say not to drag race with this clutch. I'm here just posting some info for anyone who is thinking of purchasing this clutch and you have similar power. I
When I was not drag racing the clutch held just fine with street tires and I really liked it as a street car only set-up.
I just ordered the Mcleod RXT Twin Disc after much researching.
MarkP likes this.
tucson67ss is offline  
Sponsored Links
Advertisement
 
post #2 of 29 (permalink) Old Apr 26th, 17, 11:35 PM
Lifetime Premium Member
Bill
 
Join Date: Apr 2002
Location: Winnipeg MB. Canada
Posts: 7,757
RXT for drag racing with bias slicks ? Let us know how that works out that clutch hits very hard with slicks
CDN SS is offline  
post #3 of 29 (permalink) Old Apr 26th, 17, 11:43 PM
Lifetime Premium Member
Jeff
 
Join Date: Feb 2008
Location: PuebloWest, CO.
Posts: 5,179
Re: FYI for a centerforce DF 12" clutch.

Not a clutch expert. I think that rxt will be a good choice.

78 Malibu, 402, th350, 2400, holley sniper EFI, 9" 3:70, Hoosier 27X10.50-15 Quicktime pro DOT
69 VW baja 1600cc on road off road toy. For Sale
98 s10 4.3L, auto, short bed, 3 door.
For Sale: Brodix RR-o 270cc heads, 127cc chamber. Heads they are assembled at this time. I can sell them assembled or not, PM for price. These are new and still in the original boxes. I purchased these bare and had them assembled.
http://i1044.photobucket.com/albums/...psbbffi1mn.jpg
Jebchevelle is offline  
 
post #4 of 29 (permalink) Old Apr 27th, 17, 12:08 AM Thread Starter
Team Member
Geoff Swanson
 
Join Date: Feb 2015
Location: Tucson, AZ
Posts: 601
Re: FYI for a centerforce DF 12" clutch.

Quote:
Originally Posted by CDN SS View Post
RXT for drag racing with bias slicks ? Let us know how that works out that clutch hits very hard with slicks
Will do, I will be back at the strip on the 19th of May.
tucson67ss is offline  
post #5 of 29 (permalink) Old Apr 27th, 17, 1:41 AM
Lifetime Premium Member
Mike
 
Join Date: May 2006
Location: Kapaa Kauai Hawaii
Posts: 8,684
Re: FYI for a centerforce DF 12" clutch.

Did CF have instructions to street drive 500 miles prior to track hits?

YOU KNOW YOU HAVE THE POWER..... AND IF YOU USE THAT POWER BAD THINGS ARE GOING TO HAPPEN!!

Mike Lewis street 572
http://www.lewisracingengines.com/
Holley HP EFI
Marcella Manifolds
Heads by Darin Morgan
Wires from Rick@Firecore
www.firecore50.com/
Cam by UDHarold
.456 X 1.8/1.7
Menscer Motorsports
http://menscerms.com/
R2C Filters
www.r2cperformance.com
Ultra Carbon
www.ultra-carbon.com/
GF-5R,
http://trzmotorsports.com/wp2/
TRZ FAB 9" 4.56 REM, Cryo Treated
4000 lb street car
My Showroom
aukai is offline  
post #6 of 29 (permalink) Old Apr 27th, 17, 8:30 AM
Senior Tech Team
Vinny Vince
 
Join Date: Jun 2003
Location: Thornton, Pa
Posts: 12,990
Re: FYI for a centerforce DF 12" clutch.

Quote:
Originally Posted by aukai View Post
Did CF have instructions to street drive 500 miles prior to track hits?
This. 500 MINIMUM miles and more if the car is mostly highway. Couple hundred is really not enough to knock the machining marks off the flywheel.

My 11" CF DF has survived 100+ runs in my 4000lb ~600+hp car w/o even so much as making a smell. 12" should be able to handle more tq.

*69 CHEVELLE SS EFI 502/T56 Mag/3.90
*11 C6, 6.2, 6spd
*96 Stang LQ9 6.0 turbo - everybody should have one!
69-CHVL is offline  
post #7 of 29 (permalink) Old Apr 27th, 17, 10:06 AM
Cam
Gold Founding Member
Cameron Milne
 
Join Date: Sep 1998
Location: Toronto, Ontario, Canada
Posts: 6,612
Re: FYI for a centerforce DF 12" clutch.

Are there special setup procedures for dialing in a twin clutch system? I had heard that they were fiddly to initially set up, but then you are golden.



Opportunity is missed by most people because it is dressed in overalls and looks like work.

~Thomas Edison~


My Showroom
TC Gold #120
My completely stock 67 Malibu Sport Coupe 6 cyl
Cam is offline  
post #8 of 29 (permalink) Old Apr 27th, 17, 10:13 AM
Lifetime Premium Member
Bill
 
Join Date: Apr 2002
Location: Winnipeg MB. Canada
Posts: 7,757
Re: FYI for a centerforce DF 12" clutch.

Quote:
Originally Posted by tucson67ss View Post
Will do, I will be back at the strip on the 19th of May.
Perfect be interested to hear what you think
I'm shopping for new clutch similar power have a couple friends who tried that clutch with slicks they found it a parts breaker really hit hard at launch no slip but good on street so be good to get another opinion

66 CDN Malibu SS A51,L34,M20 Aztec Bronze
Was 439ci Straub Solid Roller Brodix RR,
SOLD
,Tremec by Liberty

10.97/ 124.31 1.41 60ft
New Foxwell 475ci Power ready to go back in
Crusin / Track video http://www.youtube.com/watch?v=fhvDGOO4JAI

Engine
CDN SS is offline  
post #9 of 29 (permalink) Old Apr 27th, 17, 10:15 AM Thread Starter
Team Member
Geoff Swanson
 
Join Date: Feb 2015
Location: Tucson, AZ
Posts: 601
Re: FYI for a centerforce DF 12" clutch.

Quote:
Originally Posted by 69-CHVL View Post
This. 500 MINIMUM miles and more if the car is mostly highway. Couple hundred is really not enough to knock the machining marks off the flywheel.

My 11" CF DF has survived 100+ runs in my 4000lb ~600+hp car w/o even so much as making a smell. 12" should be able to handle more tq.
Yes, and it worked fine with my last set-up as well. It is not a break in issue. Why would you want to wear the machine marks down as they help to grab the clutch plate? If it where best to be dead smooth you would wet grind it to a 10 RA or less finish and be done with it. No break in needed!
I pussy footed the clutch for the first couple hundred miles, but did not run it at the strip for 6 months after I installed it.
Like I said "I'm not bashing the clutch" and did say they don't recommend drag racing with the clutch. I will be able to tell more when I pull the clutch.
tucson67ss is offline  
post #10 of 29 (permalink) Old Apr 27th, 17, 10:22 AM Thread Starter
Team Member
Geoff Swanson
 
Join Date: Feb 2015
Location: Tucson, AZ
Posts: 601
Re: FYI for a centerforce DF 12" clutch.

Quote:
Originally Posted by aukai View Post
Did CF have instructions to street drive 500 miles prior to track hits?

I don't recall if they put a number on it.
tucson67ss is offline  
post #11 of 29 (permalink) Old Apr 27th, 17, 10:24 AM
Lifetime Premium Member
Mark
 
Join Date: Dec 2001
Location: Colorado Springs CO
Posts: 4,120
Re: FYI for a centerforce DF 12" clutch.

Quote:
Originally Posted by CDN SS View Post
Perfect be interested to hear what you think
I'm shopping for new clutch similar power have a couple friends who tried that clutch with slicks they found it a parts breaker really hit hard at launch no slip but good on street so be good to get another opinion
Have you tried the Ram Powergrip HD? Its worked well for me on the strip.
gotago is offline  
post #12 of 29 (permalink) Old Apr 27th, 17, 10:29 AM Thread Starter
Team Member
Geoff Swanson
 
Join Date: Feb 2015
Location: Tucson, AZ
Posts: 601
Re: FYI for a centerforce DF 12" clutch.

Quote:
Originally Posted by CDN SS View Post
Perfect be interested to hear what you think
I'm shopping for new clutch similar power have a couple friends who tried that clutch with slicks they found it a parts breaker really hit hard at launch no slip but good on street so be good to get another opinion

I guess its good that I have a 9" with 31 spline axles, 1350 U joints and a bullet proof Tremec first gear. I can always take some of the hit out with shock adjustments, or more air pressure in the slicks or a combination of both.
I've never had an issue with too hard of a hit, it is usually the very opposite in that it is hard to get it to hook. That is why I switched to DA shocks.
tucson67ss is offline  
post #13 of 29 (permalink) Old Apr 27th, 17, 10:31 AM Thread Starter
Team Member
Geoff Swanson
 
Join Date: Feb 2015
Location: Tucson, AZ
Posts: 601
Re: FYI for a centerforce DF 12" clutch.

Quote:
Originally Posted by gotago View Post
Have you tried the Ram Powergrip HD? Its worked well for me on the strip.

I was going to go that route, but figured I would just spend the extra $$$ and go for a drag race recommended clutch.
tucson67ss is offline  
post #14 of 29 (permalink) Old Apr 27th, 17, 10:33 AM Thread Starter
Team Member
Geoff Swanson
 
Join Date: Feb 2015
Location: Tucson, AZ
Posts: 601
Re: FYI for a centerforce DF 12" clutch.

Quote:
Originally Posted by Cam View Post
Are there special setup procedures for dialing in a twin clutch system? I had heard that they were fiddly to initially set up, but then you are golden.
Form the research I've done it does appear to be that way. I will know for sure when the clutch arrives tomorrow.
tucson67ss is offline  
post #15 of 29 (permalink) Old Apr 27th, 17, 10:49 AM
Senior Tech Team
Vinny Vince
 
Join Date: Jun 2003
Location: Thornton, Pa
Posts: 12,990
Re: FYI for a centerforce DF 12" clutch.

Quote:
Originally Posted by tucson67ss View Post
Yes, and it worked fine with my last set-up as well. It is not a break in issue. Why would you want to wear the machine marks down as they help to grab the clutch plate? If it where best to be dead smooth you would wet grind it to a 10 RA or less finish and be done with it. No break in needed!
I pussy footed the clutch for the first couple hundred miles, but did not run it at the strip for 6 months after I installed it.
Like I said "I'm not bashing the clutch" and did say they don't recommend drag racing with the clutch. I will be able to tell more when I pull the clutch.
B/c the machine marks are reducing the pressure plate to flywheel contact surface something like 50% until they are mated. Very similar to honing a cylinder...honing leaves small ridges until the surfaces are mated. Machining the flywheel is more about getting the thing squared up properly in terms of knocking high and low spots down and leaving a finish on the surface that will facilitate proper mating of all parts. After proper mating eventually the flywheel WILL have a dead smooth finish.

FWIW I smoke a DF early on b/c I didnt break it in. I got lucky by having the flywheel re-machined, went through a 500 mile break-in and the SOB held!!!!! Saved me ~250.00 thankfully. Clutch lasted for years afterwards till I sold that trans and changed everything to the T56.

Interesting read:
Burned up clutch..need another set of eyes on this:

*69 CHEVELLE SS EFI 502/T56 Mag/3.90
*11 C6, 6.2, 6spd
*96 Stang LQ9 6.0 turbo - everybody should have one!
69-CHVL is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Chevelle Tech forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address. Note, you will be sent a confirmation request to this address.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools Search this Thread
Show Printable Version Show Printable Version
Email this Page Email this Page
Search this Thread:

Advanced Search
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome