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I think it sounds like butter on bacon, or speck or lard ... or whatever.
Clutch tamer + adjustedable clutch like RAM or B.M. with counterweights etc?

I would thing the tamer would do well with a non-adjustable "regular" clutch, or what?

A friend trying to sell me his tamer, but on my street/ strip- car I use my foot as a tamer, and on my racecar, I have an adjustable one...
 

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Adjustable clutch + 'tamer allows you to adjust the hit of the adjustable clutch separately from it's ability to hold high gear. Just set it up with enough base to hold high gear to your satisfaction (no weights), then use a 'tamer to give you the amount of slip you need for launch. If you don't have enough base adjustment available to hold high gear, add just enough weight to the levers until it does. You will then be able to adjust the launch aspect of your clutch from your driver's seat, only need to go inside the bellhousing when it's time to tighten up high gear.

There are real race cars that are winning national level races using the above method, but for street/strip cars with an adjustable clutch there's an additional advantage- it eliminates the need to go inside the bellhousing to switch back and forth between race and street clutch tunes. When you try to run the typical centrifugal assist race clutch tune on the street, it's easy to blow thru the clutch at lower rpm on the highway.

Grant
 

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Is that any different than just throwing away the adjustable clutch and going with a diaphragm?
 

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Advanced Clutches makes a new product; an adjustable (base pressure) diaphragm clutch. Light-weight unit. Pictures posted on this subject below. I spoke to Rob the other day and he sold 9 of them last week. Use the Tamer if you want along with the Advanced Clutch (but I would suggest trying it without the Tamer to start with; work your way into the Tamer if that’s what your comfortable with). But I know of one guy that picked up close to two-tenths with the Advanced Clutch over his heavy Ram & Tamer.
 

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so the advanced you are referring to only had adjustable base but no counterweights to add pressure with rpm? ive been driving clutch cars for a long time but ive never had a tamer or a slipper before so admittedly i have a lot to learn, but a diaphragm that only has adjustable base doesnt seem advantageous? do you just dial in the minimum needed to lock up which forces it to slip a little on launch but you still have to feather the pedal?
thanks for the insight.
 

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Adjustable base is an advantage with a 'tamer as it allows you to dial in an efficient amount of clutch slip after clutchless shifts. You could also adjust base by shimming the PP or swapping diaphragm springs, adjustable base just makes it easier.

Note that accel G is quite a bit higher while the engine is getting pulled down against WOT, as compared to accel G while the engine is accelerating at WOT. That extra "boost" of accel G while the engine is getting pulled down by the clutch is due to stored inertia energy exiting the rotating assy as it loses rpm. The clutch is what determines the rate that the engine loses rpm, in other words how fast the clutch pulls the engine down is what determines the rate that released energy hits the input shaft. If the clutch pulls the engine down too quick, a big portion of that released energy may end up wasted in an intense wheelspeed spike...

Rectangle Terrestrial plant Parallel Pattern Slope


Note how fast the engine is losing rpm after the shifts. Sudden loss of 2000+ rpm dumps a lot of inertia on the input shaft.

Quick bit of hillbilly physics- the inertia energy contained in an engine's rotating assy increases exponentially with rpm.
...Lets say a rotating assy spinning at 1000rpm contains 1 unit of inertia.
...Double the rpm to 2000, now it contains 4 units of inertia.
...Spin it up to 7174rpm like the launch on the graph, now it contains 51.46 units. The clutch then pulled the engine down to 4630rpm from 7174, that's 30.03 units of inertia energy dumped into the input shaft in 0.589sec. Launch hit was controlled by a ClutchTamer.
...After the shift, the engine got pulled down from 7820rpm to 5132rpm. That's 34.82 units of energy dumped into the input shaft in only 0.163sec. More energy dumped than during launch, in a far tighter time frame.

Might help to think of it like accelerating a glass by pulling on a tablecloth. Jerk the tablecloth too quick, the glass doesn't move. Pull slow and the glass moves, but not very quick. Happy medium for accelerating the glass as quickly as possible lies somewhere in between.

Basically the 'tamer allows you to dial in the inertia energy release rate during launch, adjustable base allows you to more easily adjust inertia energy release rate after clutchless shifts.

After you discover that you can control the rate that inertia energy is fed into the chassis, you will then soon realize that there's not much keeping you from raising launch rpm to make more inertia energy available during launch. Raising launch rpm allows you to take advantage of a much longer lasting inertia surge without drawing the engine down below it's torque peak.

Why start the race by "driving into the clutch" from 5500 with 30.25 units of inertia, if you can dial in a dead hook 7500 hit with 56.25 units on board without breaking anything? Being able to put that extra rpm/inertia energy to work is like adding a small shot of nitrous during launch.

Grant
 

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so the advanced you are referring to only had adjustable base but no counterweights to add pressure with rpm? ive been driving clutch cars for a long time but ive never had a tamer or a slipper before so admittedly i have a lot to learn, but a diaphragm that only has adjustable base doesnt seem advantageous? do you just dial in the minimum needed to lock up which forces it to slip a little on launch but you still have to feather the pedal?
thanks for the insight.
Advanced Clutches has a clutch dyno. He (Rob) has tested others with weights on the diaphragm and his own and he tells me it's a marketing ploy and does nothing to add noticeable clamping force. I believe he uses different steel for the “cone” but call him and discuss it with him. There is significant ET reductions due to less mass to spin and the BP adjustments. You would not slip the clutch with your foot. The clutch is basically intended for classes that require diaphragm clutches such as Coyote Stock and similar classes. If not a requirement then you would want a traditional style clutch with both BP and CW pressure adjustments. See www.advancedclutches.com
Having an adjustable base pressure on a diaphragm IS advantageous. At one time I raced with a dual 8” McLeod “Mag Force”. A total PAIN as you had to pull the clutch out to make adjustments to allow slippage but it did lead to quicker ET’s. The Advanced Clutch unit is adjustable BP through the bell housing. Much simpler!
 

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From my point of view, "significant ET reductions due to less mass to spin" could be called a marketing ploy as well. Not necessarily true when you add an external clutch hit controller to the mix.

Grant
 

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From my point of view, "significant ET reductions due to less mass to spin" could be called a marketing ploy as well. Not necessarily true when you add an external clutch hit controller to the mix.

Grant
Well I don’t know but it seems to me Advanced Clutches offers a product that is a diaphragm clutch that is quicker and the only deal I see is 1) it’s considerably lighter and 2) it has an adjustable (through bell housing) mechanism that controls the base pressure. So is it a marketing ploy if it works?
 

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Did you even read what you quoted?

When you add an external hit controller to the mix, the advantage due to "less mass to spin" in a drag race setting begins to disappear. That comes from being able to stick a launch from the same or higher rpm than you cross the stripe with, which means the clutch is no longer absorbing more inertia energy between the start/finish lines than it returns.

Grant
 

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So if a racer uses a tamer and then changes clutches and goes faster without a tamer, what does that mean???
 
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