Soft Lok Clutch on the street

Any one run one on the street?

Yes. Have been since 2004.

If it's a preset pressure plate, it will probably be "Acceptable". If it is an adjustable plate, you have to dial it in for street use and track use. It can become a time consuming task.

What have been the disadvantages of street driving with that clutch?
I only go to the track a few times a year so if i need to adjust for on or off the track doesn't bother me. I have heard some people don't adjust and leave it the same pressure for both once they find a good pressure for there car does anyone have any input on that?

I have a McLeod Soflock set at 1200# and a Ram set for 1800#. That said the Ram 3 finger, 1800# base pressure with counter weights works better for the street, because of more base pressure.’

McLeod are not very helpful with setting up a soflok PP with heavier springs, as I had Hyatt Racing set one up for me. Also, the Soflok is 10.5” pressure Plate, and the Ram has 11” PP.

Overall, I like the Ram PP, and am using the McLeod Sintered Iron disc.

Mark

Yes, I have run one on the street for five years. When I leave the track I add 3 turns of base pressure. I send it in every couple years and have it rebuilt.

Thanks for the reply and pics, Seeing the pics helps a lot, I like the removable cover on the bell housing.

Did you add the window?

Yes, you have to send the scatter shield in and have the window.

That's one of the disadvantages of the sintered iron disc. It needs to be adjusted. You also really need an adjustable pressure plate. When I stated using mine, I couldn't buy an adjustable plate, so I'd make 6-8 hard runs, pull the clutch and take it to a local friction house and have the pressure dropped.


I started at 1200 and ended up at 660 pounds with no counter weight.

I can't imagine needing 1800 pounds. Sounds like a parts breaker.

I update my clutch a few years ago. I now have an adjustable PP. On the street I use about 950 pounds of base and about 12 grams of CW to keep it from slipping. At the track, depending on conditions I start at about 500 and 10 grams of base and work from there.

Can you use any disc or do you need something special?

At 1000 HP, you will need the 1800 lbs with the sintered Iron disc, or you will glaze the hell out of the surfaces on the street. I use the Ram Long PP and 11”

The GTX has about 680 HP, and that one I have 1200 lb, and does in fact slip some on take off on the street, and it is the McLeod Soflok which is 10.5”

Both PP are counterweighted, and for the track I adjust both down to about 200 - 250 lbs via the access hole on the bottom of the Bell.

Madscientist is right, if you try to launch on the track with 1200-1800 lbs, they will be parts breakers.

Tim Hyatt (RIP) told me that you need 1200-1800 lbs of base pressure for the street, otherwise you will glaze up the flywheel and PP surfaces. He told me that his son Chris runs the higher base pressure for the street, and it works great.

I am by no means an expert, and just followed Tim Hyatt’s advice since he was the premier expert with clutches for high HP cars. Oh, BTW, both of my cars are around 3500 lbs...so pretty heavy!

Mark

It uses a sintered iron disc.

Where did you send the bell housing for the machining of the access plate??

Back to Lakewood. When I did mine it was 275.00 plus shipping.

I sent the Bellhousing to Hyatt Racing, as Lakewood did not want to do it.

Mark

Is someone still working at Hyatt?

I really don’t know, I think Tim’s son Chris was moving to a small shop, but he may be just doing SFI Certs now...I do know that Chris will return your email, but I think he is just working part time.

I did not get a good feeling the last time I talked to Chris, so I bought my last custom clutch from RAM.

Mark

As of the middle of last year, Chris was still adding windows and certifying bell housings. Pretty sure he is still doing clutch work, too.

Thanks. That's what I was asking.

I just received one of the two bells I sent to Hyatt. It's really, really nice and Chris is great to work with.

Not only did he add the window, the surfaced it to square it up. I was really impressed with that.

What did it cost and how long did it take? I had to wait almost 2 months for Lakewood and that was 2 years ago.

I have a second bell housing I need windowed. I have no problem using Hyatt.

I try to remain silent and out of the BS on most group chats but adj clutches on the street are close to me heart and I cant understand some of the stuff I hear......



Guys claim that you cant chassis dyno a slipper clutch... incorrect. You are in high gear for a longer period of time on the track then any dyno pull.... so if it slips on the dyno, I guarantee it is going to drive through the clutch at the track! if you are concerned and don't want to risk anything, put a couple turns of base in...

I have driven my car around on the street for years with less then 400#'s of base and 12 grams on each finger..... worked perfectly.. car made 840rwhp and weighed 3765

If you are worried about driving through the clutch on the street, just gear down and keep the revs a bit higher or add a couple turns of base! using shims or re-setting your heights is key to making sure the clutch works how you want it!

Chris Hyatt is still doing clutch work and can service all you stuff, have been working with him since his dad passed and he has been awesome!
He is a perfectionist at his work and will treat you right!

Those rams clutch's work ok, but I'm not a fan that they cant go lower then 800#'s on the BBC set up... I had a friend run one and we ended up with less then 1 turn of base and it was still hitting the tire too hard, he took it out and put back in a soft lock.

Nice to see some rational, real world experience on this issue. Chris is one of the good guys for sure and I cannot imagine anyone being disappointed with his service.

Straight poop right here^^^^^^^^^^^. I also disagree with all that base load. Ram loves it. I have the broken parts to prove you can break parts with big plate loads.

Agreeing or disagreeing with what I said???

What kind of parts?

Absolutely agreeing with you. 100%.

Well, Tim Hyatt told me to run 1200 - 1800 base on the street, and 200 base on the track. He was the foremost expert, and I will listen to him!

He did tell me not to drop the clutch with high base pressures, otherwise parts breakage will happen.

He set up my clutch that I posted pics of.

Mark

PS: Yes, Chris did the inspection/adjustment plate for me on the bell I posted.

Here are a few more pics that I took of Tim's work...Tim also put together a really nice custom manual for driving a Sofloc Clutch on the street for me, for both the Lenco in my GTX, and the Brewer A833 (Passon Geared) in my Super Bee.

I am no longer an active racer, but still like to hit the track one a year at Mopar events.

Mark

I get why he likes the high base loads on the streets. Some guys will drive through the clutch because they won't downshift and think they should be able to run around in high gear at 2200 and mash the clutch.

Madscientist, Tim told me that I should do rolling launches on the street, and absolutely NO dry burnouts! He also told me to "baby" the A833 with high base pressures.

With the Lenco, he still told me no dry burnouts, and easy on the high base pressure launches, but the lenco was more forgiving, and softer due to the internal transmission clutches.

Bottom line, he told me to use common sense ;-))

Tim mentions I his manual that I should routinely blow-out the dust in the bellhousing, and wipe it down through the access window.

Regards, Mark

I would like to have one of those trans in my 64! Good pic on the mounts too.
Looking at the clutch, how do you determine the poundage? I know absolutely nothing on this.

Thank you, Cudaman!

I kind of fudged up on the mount...I need two more bolts in front of the tray/mount. Just have not got around to it.

I also since added tubular CM fore/aft limiters as well that will help keep the trans in place.

Mark

I've looked at a few but don't know which to stay away from, new is still way out of budget for now.
I would have to keep part of the stock crossmember too because I'm still have t-bars. Are all the good clutches long style or are some B&B?

Tim told me that the Long style were the best for very aggressive Street and Strip. Big plus is the adjustability!

I still have the Torsion bars, and I do not notice any movement of the floor or crossmember sides.

As insurance, I am going to buy the US Cartool frame connectors, and just straddle the square couplers that are already welded in place, and also install Resto Ricks front/rear torque boxes. That should strengthen everything up even more.

Driving the ST1200 on the street really is very strange, as I keep going for the clutch between shifts...don't need to do that. Once it is going, just keep up shifting, and downshifting with foot off the gas, as it freewheels on the internal sprags.

Mark

For a street/strip application that isn't clutchless, a good diaphragm combined with an engagement buffer is going to be a far better choice than the typical SoftLoc style clutch. Less maintenance, less broken parts, and adjustable engagement without going inside the bell. No need to change settings from street to strip, no worrys about lugging the engine and burning up the clutch.

This style clutch might be something different to many of you, but look at what the NMRA Coyote Stock sealed crate engine class is doing with it. They race heads up on a pro tree, and everyone has the same engine. Both automatic and stick trans are allowed, both run at the same weight. Automatics are allowed any converter and a trans brake, sticks are required to run a minimum 10" dia single disc diaphragm clutch. I don't think there are any competitive automatics in the class, most all are sticks running the diaphragm/ClutchTamer setup. Running at 3175lbs, those $6500 NA 302ci sealed crate engines run 10.0 @ 132. The guy in this link isn't using a sealed engine, but it sets the NA Coyote record on it's 3rd pass using the exact same clutch setup, 9600rpm with a diaphragm PP... NA Coyote record run

Weedburner, What is an engagement buffer? Diaphram Clutch? Dual disc?

Thank, Mark

http://clutchtamer.com ?

Hmm never heard of those

Yeah it's a screen door damper with some fancy brackets

Gus

Got it book marked

I've been thinking of going to a softloc clutch also for my Dart. I have a McLeod Street Twin in it now. I know the pressure plate is some-what adjustable. More than that.....I don't know. I'm reading and learning here. It also is a matter of how much I want to mess with stuff under the car. I'm getting older......

It's not bad if you have a window in the bell housing. I know a Stock racer who drilled a 1 inch hole in the face of the bell housing. He sets his static pressure through the hole and doesn't mess with counter weight.


Not having a window in the can would be a nightmare at my age.

No window in my Lakewood housing.... Would have to do that.

There are a few clutch buffers out there. Except for the ClutchTamer, most are for hydraulic release systems. Here's some links...
...Tilton Flow Control Valve
...Magnus Launch Control Device
...Clutchmasters Flow Control Valve
...ClutchTamer Clutch Slip Controller

Here are the basic differences between the "Magnus Launch Control" , the "Clutch Masters flow Control Valve", and the "ClutchTamer Clutch Slip Controller"...

1- Magnus unit requires "pre-loading" the clutch before launch to make the best of delayed reaction times.
...Clutch Masters also requires "pre-loading" the clutch before launch to make the best of delayed reaction times.
...No pre-loading with the ClutchTamer, and no delayed reaction times.

2- Magnus requires a solenoid bypass to solve it's problem of excessive clutch slip after WOT shifts, resulting in clutch engagement after WOT shifts that's too aggressive.
...Clutch Masters unit has no bypass solenoid, requiring a compromised launch with very little clutch slip to prevent excessive clutch slipping after WOT shifts.
...Clutchtamer strikes a balance between those extremes, creating a happy medium amount of clutch slip after WOT shifts that results in a quicker pass while simultaneously reducing impact on drivetrain components.

3- Magnus solenoid bypass allows quick return of the clutch pedal, meaning each push of the clutch pedal begins at the top of it's travel and includes the deadband travel.
...Clutch Masters unit has some clutch pedal return delay, but with it's compromise setting it's still quick enough that each push of the clutch pedal begins at the top of it's travel and includes the deadband travel.
...ClutchTamer controlled pedal does not have enough time to return to the top before WOT shifts, which effectively shortens pedal travel resulting in quicker WOT shifts.