I currently have an 11" McLeod borgen beck w/100series disc the pp is 2400lb. It just started slipping in 4th so time for a new one @#$^&%$ even though it was rebuilt 1700 miles ago?

Does anyone use and recommend the 12" in any brand?

I am looking at replacing with Mcleod diaphram style 2850lb PP and 12" 800 series disc or Centerforce dual friction!

my concerns is the differences in shifting especially downshifting with 12" vs. current 11". Vendor stated that this could be slowed some with 12".

Also what about the centerforce dual friction experiences, there website is not the best for info on PP lbs etc..

Any input is appreciated, SS.

According to Centerforce, the DF kit has 90% more holding power than stock,..FWIW. I run DF's in four cars,..no problems. One car is built 496 and no slipping yet after about 5000 miles,..plus the pedal pressure is as light as new Nissan.

Don't know what bellhousing you have that would accept a 12" clutch, but I have a a good aluminum GM bellhousing from a truck that's designed for 12 inchers. $90 with shipping. Send me a PM isf interested.

I have the McLeod 12" behind my 502 and inside a McLeod scattershield with a centerforce flywheel.

Once I cleared up some minor interference issues between the scattershield and pressure plate (search my post history for that story), it fit and works great. The interference would not have been a problem if I used a McLeod flywheel. The centerforce is thicker so the mechanical stack up of the parts made the tallest outer part of the pressure plate touch the inside of my scattershield. I solved it by kissing the high spots on the pressure plate with an angle grinder once I got the OK from the tech guys at McLeod.

Grabs fast and solid with no slippage.

It downshifts fine, but yes, the added diameter and weight adds up to more rotational force for the trans to synchronize with, so downshifting is a tad slower than with an 11".

Tim

I currently have an 11" McLeod borgen beck w/100series disc the pp is 2400lb. It just started slipping in 4th so time for a new one @#$^&%$ even though it was rebuilt 1700 miles ago?

Does anyone use and recommend the 12" in any brand?

I am looking at replacing with Mcleod diaphram style 2850lb PP and 12" 800 series disc or Centerforce dual friction!

my concerns is the differences in shifting especially downshifting with 12" vs. current 11". Vendor stated that this could be slowed some with 12".

Also what about the centerforce dual friction experiences, there website is not the best for info on PP lbs etc..

Any input is appreciated, SS.

12" clutches are for milk trucks, stay with an 11", just get a better disc than what you had, the 100 series is the problem. stay away from anything with more than 2400lbs of plate pressure for a street car, its just not necessary with the right friction material.

I am going with an 11" again. One thing to note the 800 series disc requires more pressure and the PP is rated at 2900lbs.

One thing I have been considering is the flywheel thickness and if it is close to or surpassed the minimum thickness. Reason being that I had disengagement issues (notchy shifting/going into gear) required me to increase my linkage throw and I think made the disc wear prematurely. Angles seemed right according to everything I read but free play was not correct.

I used an adjustable ball stud and it turned out being .25" longer than the GM fixed ball stud. I now will be replacing the clutch fork with heavy duty unit and possibly the adjustable length T/O.

It was either flexing or????? Flywheel is too thin?

This should be really easy to set up, so why did it wear so fast is the question!

More input?

Thanks, SS.

SS,
Don't know where you are on this heavy duty fork, but its been mentioned here that it will cause some firewall clearance issues? GM still makes the factory fork , last 3 numbers 632. JimM mentioned the part number so you can do a search here on this. The issue was clutch fork hitting the firewall.
Also, if you dont know, the correct adjustable pivot ball height is 4.750" from the ball face to the back of the block. If you have a block saver plate, deduct that clearance.

Don't know where you are on this heavy duty fork, but its been mentioned here that it will cause some firewall clearance issues? GM still makes the factory fork , last 3 numbers 632. JimM mentioned the part number so you can do a search here on this. The issue was clutch fork hitting the firewall
This is the Lakewood heavy duty clutch fork in question LAK-15500 and yes it will hit the firewall (personal experience) I noticed that Summit racing no longer list it as fitting Camaros.

Just my .02 I have used the Centerforce dual friction clutch and abused it regularly. It has held up fine and pedal pressure is light.