i want to know if any of you operate a 4 speed maverick at the drag strip ?? my question is my 347 is rated at 475hp and 440lbt and i have aluminum 157 flywheel to put a 10.5 cluths set,,, wath did you used ? zoom hp or centerforce or hays street and strip i plan to drag with slick ,,, i need your experience ,thanks
I'm running a Centerforce in mine with alum flywheel...now I just need a good z-bar to hold up to it. I'm also running a 347, trickflow heads, toploader, 4:30 gears, M/T drag radials. No dyno yet but I got a 6.97 out of it in the 1/8 mile. I think the Centerforce is an awesome clutch setup, especially for a street car like mine. Not bad on the leg muscles at all and I just got off a 500 mile weeklong cruise in with it about 2 weeks ago. Good luck with it.
I've been told the 3 finger pressure plate can hold more hp whereas a diaphragm pressure plate hp will blow right through it. When I changed the clutch last year I went with a Ram Iron/Organic disc. It is not fun to be stuck in traffic. Zoom clutch are made in China. Ram and Centerforce are made in the USA. http://www.ramclutches.com/Specialty%20products/900_series.htm
Because of the design of the diaphram clutch the spring plate tends to flatten out with high RPM. That lets the clutch slip - generating heat - causing booms. The long type (three finger) is built so that as rpm increases so does clutch pressure. The twin and tripple disc clutches used by the "big boys" are long type clutches that are operated like a centrifical clutch. The pedal is used to engage the clutch at an idle for staging. The long type clutch is best for drag racing.
Guys. I may not be pumping out the HP that you guys are with my Hi-Po hybrid 289/302, but I've always used a Hays, long style, 10.5" and have had great success with it. Street and /or strip.
Give these guys a call, Ask for a guy Called "Coupe "( I think his real name is Matt). These guys build a lot of Mustang clutches and flywheels. They are racers themselves. Good people. http://www.specclutch.com/ EDIT: Clutch technology like everything else has progressed Thur the years, No longer do you need legs of steel to use a HI-PO clutch. Most diaphragm performance clutches now have flyweights that help with clamping force at higher rpm. Case in point, One of our Mustangs required a clutch change a while back, It had one of the diaphragm pressure plates with the duel friction disk. Upon removal we noticed the clutch at one time had bitten so hard it had actually left an impression of the pucks in the flywheel. As long as the free travel is rite we have no slippage problems in none of our cars. (all are supercharged some also have nitrous) As i stated clutch setups are not like they used to be they are a lot better. Even in our Tandem dump trucks the clutch can be disengaged with your hand, Try that on a old clutch setup, And your likely to break something.
Back in the late 70's I ran a 71 Comet with a 4 speed and a built 351W that ran 12.50's. I used, if I remember right, a Schaefer steel flywheel that was drilled for an 11in. pressure plate. This allowed for use of a big block long style clutch and I never had a slippage problem. It definitely requires that the Z bar be reinforced. Just my two cents. Lee "THE MAV" Richart
Had a van once with a stick in it and a diaphragm clutch. One day it started squealling like a pig from the bell housing and within a minute, the seized throw-out bearing had worn straight thru the fingers of the clutch disc. Haven't bought one since. At least the long style will give you a grace period of more than a minute.
The last Long-style I ran was a Hayes Street/Strip 10 1/2". One of the pp cover bolts broke, jamming the clutch while I was about 20 miles from home. I got it home but it ruined the main thrust bearing and the crankshaft. Went with a CenterForce diaphram setup, same holding power, less pedal effort and no high rpm problems with the counterweighted fingers. Ran it behind a nitroused 347 for a couple years without slipping.
Ray, you mention needing a good Z bar to hold up to this clutch. I have a CNC hydraulic push type slave cylinder that I was going to use. Would you think that this Centerforce requires something more beefier than the hydraulic release?
I really don't know. I've read where many people have had the factory z-bars fail on them. The centerforce clutch doesn't seem to have much more pressure than a stock clutch but it obviously does. I will seriously consider going to cable or hydraulic in the near future. I think I may try one of the a/m AutoKrafter z-bars first. They are supposedly a lot stronger.
I've got this Cleveland going in with Mustang II suspension and more conventional type headers than the Tubulars that I used originally. A stock Z bar won't be an option anyway. I'll try the hydraulic system and see what happens. Thanks.
