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Should you delete your clutch helper spring? TLDR: Yes*
I come to you all a couple of steps removed from the S550 Mustang community, where deleting the clutch helper spring is a common and well-liked mod. Ford even liked it so much that they deleted the thing from the factory in the later years of GT350 production, ending years of internet speculation that doing so would somehow break the clutch master cylinder. Just kidding, some chunk of the internet still thinks that’s true.
What is a clutch helper spring?
Well first of all, it isn’t necessarily a clutch return spring. The main purpose of clutch helper springs is to help you push the clutch, particularly in the later half of clutch travel. This is achieved using geometry tricks to mechanically disadvantage the spring at the top of clutch pedal travel, or even reverse the direction the spring pushes a small amount. In the S550 Mustang, the clutch helper spring is on two pivots at either end and breaks over center at about one quarter of the travel to the floor. The effect this has is that the clutch helper spring is pushing the clutch pedal to the floor at the bottom of travel and slightly pushing the pedal towards you at the top of travel. In the middle, it does nothing.
So why do OEMs do this?
My speculation is that by reducing the clutch pedal effort, they hit some mysterious corporate target of “how heavy is too heavy.” Bear in mind that they have to do this without also making the clutch too light at the top of travel, which could induce unwanted slip. So in comes the geometry tricks. And they’re not great for intuitive clutch pedal operation. Your brain can easily train itself to things that are consistent, which is why we all like brake pedals that push back harder and harder the more we press on them. And most of us will hate brake pedals in electric cars that have this weird hitch in them that transitions between regen braking and hydraulic braking.
The clutch helper spring is doing the same sort of thing to your clutch pedal: if you feel like the clutch has a weird hitch in it, you aren’t crazy. In fact, the clutch pedal pressure actually decreases very slightly in the second half of travel with the clutch helper spring installed. Imagine if your brakes worked like this. You’d go nuts. And if you learned to drive stick on a car without a clutch helper spring (which is probably most of you) then you might be wondering if you’re insane when you feel that hitch in the clutch pedal.
How much of a difference does it really make?
Below is a chart of the clutch pedal pressure in pound-force over the full range of travel of the pedal in half-inch increments from fully out to fully to the floor. I measured the total clutch pedal throw at 5-3/16”, so I didn’t measure the last 3/16” of travel in order to avoid hitting the hard stop.
Methodology note: This chart was constructed with six sets of measurements, three before (stock) and three after (spring removed.) I averaged the three sets for each state together to create the chart data. In order to achieve accurate and repeatable measurements, the pressure was not recorded with the pedal completely static. There is some friction in both directions of movement in the system as a whole, so as you push the pedal down the weight you measure at a certain position will be greater than the weight you measure on the way back up at that same position, due to friction/drag. This variance won't get you clean data if you're only measuring a static position, so these numbers were all recorded as the pedal was being slowly pushed down for consistency.
The red line you see above is the stock clutch pedal pressure curve, and the yellow line is the pressure curve with the helper spring removed. As you can see, our cars have a similar “break over” setup to the S550 Mustang. In the first approximately 2.4 inches of travel, the spring is actually acting as a very weak return spring, increasing pedal effort by around 2.5 pounds and tapering down to zero by the 2.4 inch mark. After 2.4 inches of pedal travel, the pivot points on the spring break over center and there is a dramatic difference between the two curves. The pressure curve of the stock setup actually goes slightly negative, meaning that pushing the pedal further actually results in less pressure on your foot. Note that there's still positive pressure at each point (otherwise the pedal would flop to the floor on its own) but the further you push, the more the pressure drops. This is similar to how a compound bow works, just less dramatic. After 4.5” of travel they both sharply dip up, which I assume is something caused by the clutch itself rather than the pedal or hydraulic cylinders.
Looking at the stock pressure curve in isolation (below) it’s quite easy to understand why the clutch pedal feels the way it does and why it’s unintuitive. The more you push, the harder it should push back. Our brains like that. The stock pedal doesn’t meet that standard. It is non-linear in the extreme.
The effort to push the clutch pedal fully to the floor increases from 26.4 pounds to 30.7 pounds with the helper spring removed. So if an extra 4.3 pounds of pressure (or a 16% increase) is a deal breaker to you, then you may want to think twice about doing this. I get that some people have knee injuries and a stock clutch pedal may be the most they can deal with.
Never mind the numbers, what is the actual experience like?
My subjective assessment of this mod is that the clutch now feels NORMAL. My other vehicle is a manual Tacoma that has a normal clutch pedal without a helper spring, and my ITS now feels much more like that than… whatever Honda was trying to achieve. I always have the rev matching turned off, and while I was able to rev-match pretty well before during casual driving, it’s better now. What is substantially better is my ability to aggressively upshift and heel-toe downshift. Before, it felt like I was up against the steepest slope of the learning curve of this car. Now it’s intuitive and I nail it just about every time.
Does the pedal sag?
In my 2025 DE5 ITS, no it does not. The clutch master has an internal spring, so there's pressure on it even at the top of pedal travel. If the pedal is properly adjusted, the clutch master runs out of throw when the pedal contacts the factory-adjustable stop. If this isn't the case on your car, adjust the arm on the master or the stop on the clutch pedal frame, or both.
Does this interfere with the operation of cruise control?
No, but if your clutch pedal is out of adjustment there could be some sag in the pedal that might cut throttle intermittently. See above regarding pedal adjustment. My car has no issues with this and I did not have to adjust anything.
Can you go back to stock?
Yes, but it won't be quite as easy as removing the spring. You'll need to remove the clutch pedal assembly entirely. It's secured to the firewall with three bolts, there are two sensors that need unplugged, and the clevis pin removed from the clutch master cylinder. The top bolt on the firewall is the most difficult, but you'll be able to get it with extensions and a universal joint. Once removed, the clutch helper spring can be reinstalled from the back side.
So how do you remove it?
If a 16% increase in pedal pressure doesn’t sound like a deal breaker, I highly encourage you to try this simple mod to improve the linearity and feel of the clutch pedal. It can be done with nothing more than a flashlight and a large, flathead screwdriver. While it’s not quite as simple as removing the setup on an S550 Mustang (I can remove those one-handed, no tools and without looking) it isn’t all that hard. If the S550 Mustang is a 1/10 for difficulty, this is a 3/10. You have to get into a small area, upside down, and coax that spring out of its spot. This is best explained in video, so that’s what this video covers:
I come to you all a couple of steps removed from the S550 Mustang community, where deleting the clutch helper spring is a common and well-liked mod. Ford even liked it so much that they deleted the thing from the factory in the later years of GT350 production, ending years of internet speculation that doing so would somehow break the clutch master cylinder. Just kidding, some chunk of the internet still thinks that’s true.
What is a clutch helper spring?
Well first of all, it isn’t necessarily a clutch return spring. The main purpose of clutch helper springs is to help you push the clutch, particularly in the later half of clutch travel. This is achieved using geometry tricks to mechanically disadvantage the spring at the top of clutch pedal travel, or even reverse the direction the spring pushes a small amount. In the S550 Mustang, the clutch helper spring is on two pivots at either end and breaks over center at about one quarter of the travel to the floor. The effect this has is that the clutch helper spring is pushing the clutch pedal to the floor at the bottom of travel and slightly pushing the pedal towards you at the top of travel. In the middle, it does nothing.
So why do OEMs do this?
My speculation is that by reducing the clutch pedal effort, they hit some mysterious corporate target of “how heavy is too heavy.” Bear in mind that they have to do this without also making the clutch too light at the top of travel, which could induce unwanted slip. So in comes the geometry tricks. And they’re not great for intuitive clutch pedal operation. Your brain can easily train itself to things that are consistent, which is why we all like brake pedals that push back harder and harder the more we press on them. And most of us will hate brake pedals in electric cars that have this weird hitch in them that transitions between regen braking and hydraulic braking.
The clutch helper spring is doing the same sort of thing to your clutch pedal: if you feel like the clutch has a weird hitch in it, you aren’t crazy. In fact, the clutch pedal pressure actually decreases very slightly in the second half of travel with the clutch helper spring installed. Imagine if your brakes worked like this. You’d go nuts. And if you learned to drive stick on a car without a clutch helper spring (which is probably most of you) then you might be wondering if you’re insane when you feel that hitch in the clutch pedal.
How much of a difference does it really make?
Below is a chart of the clutch pedal pressure in pound-force over the full range of travel of the pedal in half-inch increments from fully out to fully to the floor. I measured the total clutch pedal throw at 5-3/16”, so I didn’t measure the last 3/16” of travel in order to avoid hitting the hard stop.
Methodology note: This chart was constructed with six sets of measurements, three before (stock) and three after (spring removed.) I averaged the three sets for each state together to create the chart data. In order to achieve accurate and repeatable measurements, the pressure was not recorded with the pedal completely static. There is some friction in both directions of movement in the system as a whole, so as you push the pedal down the weight you measure at a certain position will be greater than the weight you measure on the way back up at that same position, due to friction/drag. This variance won't get you clean data if you're only measuring a static position, so these numbers were all recorded as the pedal was being slowly pushed down for consistency.
The red line you see above is the stock clutch pedal pressure curve, and the yellow line is the pressure curve with the helper spring removed. As you can see, our cars have a similar “break over” setup to the S550 Mustang. In the first approximately 2.4 inches of travel, the spring is actually acting as a very weak return spring, increasing pedal effort by around 2.5 pounds and tapering down to zero by the 2.4 inch mark. After 2.4 inches of pedal travel, the pivot points on the spring break over center and there is a dramatic difference between the two curves. The pressure curve of the stock setup actually goes slightly negative, meaning that pushing the pedal further actually results in less pressure on your foot. Note that there's still positive pressure at each point (otherwise the pedal would flop to the floor on its own) but the further you push, the more the pressure drops. This is similar to how a compound bow works, just less dramatic. After 4.5” of travel they both sharply dip up, which I assume is something caused by the clutch itself rather than the pedal or hydraulic cylinders.
Looking at the stock pressure curve in isolation (below) it’s quite easy to understand why the clutch pedal feels the way it does and why it’s unintuitive. The more you push, the harder it should push back. Our brains like that. The stock pedal doesn’t meet that standard. It is non-linear in the extreme.
The effort to push the clutch pedal fully to the floor increases from 26.4 pounds to 30.7 pounds with the helper spring removed. So if an extra 4.3 pounds of pressure (or a 16% increase) is a deal breaker to you, then you may want to think twice about doing this. I get that some people have knee injuries and a stock clutch pedal may be the most they can deal with.
Never mind the numbers, what is the actual experience like?
My subjective assessment of this mod is that the clutch now feels NORMAL. My other vehicle is a manual Tacoma that has a normal clutch pedal without a helper spring, and my ITS now feels much more like that than… whatever Honda was trying to achieve. I always have the rev matching turned off, and while I was able to rev-match pretty well before during casual driving, it’s better now. What is substantially better is my ability to aggressively upshift and heel-toe downshift. Before, it felt like I was up against the steepest slope of the learning curve of this car. Now it’s intuitive and I nail it just about every time.
Does the pedal sag?
In my 2025 DE5 ITS, no it does not. The clutch master has an internal spring, so there's pressure on it even at the top of pedal travel. If the pedal is properly adjusted, the clutch master runs out of throw when the pedal contacts the factory-adjustable stop. If this isn't the case on your car, adjust the arm on the master or the stop on the clutch pedal frame, or both.
Does this interfere with the operation of cruise control?
No, but if your clutch pedal is out of adjustment there could be some sag in the pedal that might cut throttle intermittently. See above regarding pedal adjustment. My car has no issues with this and I did not have to adjust anything.
Can you go back to stock?
Yes, but it won't be quite as easy as removing the spring. You'll need to remove the clutch pedal assembly entirely. It's secured to the firewall with three bolts, there are two sensors that need unplugged, and the clevis pin removed from the clutch master cylinder. The top bolt on the firewall is the most difficult, but you'll be able to get it with extensions and a universal joint. Once removed, the clutch helper spring can be reinstalled from the back side.
So how do you remove it?
If a 16% increase in pedal pressure doesn’t sound like a deal breaker, I highly encourage you to try this simple mod to improve the linearity and feel of the clutch pedal. It can be done with nothing more than a flashlight and a large, flathead screwdriver. While it’s not quite as simple as removing the setup on an S550 Mustang (I can remove those one-handed, no tools and without looking) it isn’t all that hard. If the S550 Mustang is a 1/10 for difficulty, this is a 3/10. You have to get into a small area, upside down, and coax that spring out of its spot. This is best explained in video, so that’s what this video covers:
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