Another way to understand how anti squat prevents squat during acceleration: when accelerating the tires create a force in a vector connecting the tire patch to the CG. If the rear arms pivot at the same angle as that vector, the car won’t squat at all. The larger the difference between the angle of the arms and that vector the more of the force gets transferred to the shocks, and therefore more squat.
Good video. A very good tuning option that also gets overlooked quite a bit. Especially for newer drivers/racers. I usually don't adjust mine. I'll set it once during the build and its usually good to go depending on if I'm building for the one carpet or the 3-4 clay tracks here. Generally I'll go between the lowest to only as high as 2 ° I found with my Serpent 2wd cars, they liked the squat at 0.5° on both carpet and clay.
Actually you're almost on the opposite side of how anti squat affects the forward bite, as far back as when the old gold pan RC-10 first came out the factory guys (Jay Halsey) said to improve the forward bite by placing around a .040 shim (I use one of the aluminum spacer washers for the body mount posts) between the front of the chassis plate and the front of the rear arm mounting blocks. I have always just cut out a slot in the aluminum washer I use and slide it in place over the mounting screw so it is between the tub and the arm mounts. The only thing I have ran into is with too much anti squat it can lift hard enough on the back of the car to actually extend the shocks to full extension and make the car start to "pogo" off the shocks because they are now just like a solid mount. Think of anti squat as pushing down on the rear tires actually increasing forward bite by pushing the tires down into the track surface, I have found that even though mechanically it doesn't physically add side bite it can do a very good job of doing so because if you toss it into a corner a little on the hard side by jumping on the power it adds enough instant forward bite to instantly stop the slide. If you watch a dirt modified or late model you can see the effects of a ton of anti squat and the instant forward bite it gives the car by how it forces the rear of the car to lift and that pushes the rear tires harder into the track surface. A lot of people don't understand that is what's happening and think when the rear of the car lifts that it's lifting the tires also and takes away the bite. But you can do an easy demonstration by putting a length of stiff wire or a strong piece of tubing so it sits on top of a rear a arm and under the chassis in front of the rear arm mounting blocks, the closer you can get to the center of the wheelbase the better. Now using that length of what ever you could find push down towards the ground and lift the front of the chassis up, did you notice what that did to the rear tires and the side effect of what happened to the rear shocks? You should have seen the tires develop a flatter contact area to the ground and it made the rear shocks extend further. THAT is what anti squat does for the rear bite it's like adding a couple of pounds of weight right over the rear tires and unlike a force that causes the rear of the car to rotate around the center of the rear axles causing the front of the car to lift up and the rear to squat down like the old drag cars did doing a wheelstand you aren't wasting torque and power trying to make the rear gears climb over each other using a lot of power and NOT making good use of it. Just search for adjusting four link rear suspension and using a torque arm fifth spring setup to increase bite on a dirt track race be it a modified or a late model, even better find a video on UA-cam
I crank anti squat to 4deg or max on my ae b4.1 t4.2 & 22t4.0 for more traction and straight line stability on very loose low bite surfaces. Way better control and grip then 1.5deg. Learned this from Schumacher manuals that have the best tuneup advise lv come across.
your tuning videos are by far the best on Y.T. thanks for sharing your thoughts.. and p.s. who ever gave this vid a dis like should be whipped repetedly..lol thanks again renoldo..
Yeah, I suppose that would keep the car more level under breaking. So a negative anti-squat in the rear is a bit like a positive anti-dive in the front.
Thanks for the video! Not sure if this relates to the video but I'm finding my 4wd buggy is going wheelies at times after a wall ride at my indoor track. It's high traction, I've set it to a loose slipper and once I get on full trigger coming from the wall... It's there where it can wheel... Do you think it's a matter of reducing punch. I have an esc that controls two levels of punch... Buggy is fine elsewhere on the track
+ayske1 My B44 would do that if I ran open cell foams and if I hit a bump. The front would kick up and the rear tires would expand and make the care wheelie on the straight. It was hella fun, but hard to drive. In your case, if the track is high grip, you may simply have too much stiffness in the rear suspension. Springs, pistons, oil, anti-squat, shock angle. Try the simpler things first, like standing the shocks up more, then anti-squat, and then springs/oil/pistons.
@1:02, your description is exactly the opposite of what XRay setup helper says. Less anti-squat is better for a bumpy track. More anti-squat is more suited for smooth high grip tracks.
There are a few ways to look at this. On bumpy tracks, the bumps push against the arm. More anti-squat allows the bump to push against the arm at a shallower angle and cause the suspension to compress more, essentially causing the tires to skid less over the bumps, thereby giving you more trip (or causing you to lose less grip). However, if other parts of the same track are smooth but low grip, more anti-squat will hurt you there, as it's essentially acting like a stiffer rear spring on a loose surface. So whether to run more anti-squat on a bumpy track really depends on how much of the track is bumpy, in combination with how grippy or loose the surface itself is. On smooth, low grip tracks, less anti-squat is generally the way to go, as it allows the suspension to give more and therefore reduce how much the rear tires break traction. On smooth, high grip tracks, more anti-squat is better, as you already have the rear grip from the track surface and so you can use anti-squat to avoid excessive rearward weight transfer and give you more on-power steering.
@@doctormosfet Don't mean to attack, but your response mixes different scenarios and so it becomes a "depends." With more anti-squat, rear suspension compresses less and less camber change, therefore more contact patch during acceleration, which means higher *forward* traction. Car is also bouncier with more anti-squat because geometry is stiffened, which means less conducive to bumpy surfaces. Knowing the basic facts, one can then use judgement and experience to tune the car based on the track condition.
I've had situations where I wasn't sure whether to use more or less anti-squat, because the track had a mix of what could justify either case. There is a science to it, which is why "it depends," but ultimately judgment is informed by experience, which in turn is informed by experimenting with these things.
@@ihcnehc there's no real answer that's why, everything is balancing and the goal is to secure the benefits of a type of adjustment by finding the range where it is present. Perhaps a little antisquat will help decrease weight transfer for better turning but too much added and you would begin to feel the effects of less rear grip and they would outweigh the benefit increased steering gave.
@@rcbuggies57 Thanks for your feedback. Mechanically, raising anti-squad also raises roll center, essentially stiffens your rear suspension geometry. As a result, the rear end dips less when car is on power ( thus less F -->B weight transfer ) and rolls less when turning and "pops" a little more when jumping. I thought doctormosfet's "There are a few ways to look at this..." comment from the 4th sentence on was spot on. Prior to that, I am not sure if he was referring to a genuinely bumpy surface or some artificial bumpy rhythm section.
Your suspension setup videos are still an absolute godsend, 7 years after you made them. Thanks dude
Another way to understand how anti squat prevents squat during acceleration: when accelerating the tires create a force in a vector connecting the tire patch to the CG. If the rear arms pivot at the same angle as that vector, the car won’t squat at all. The larger the difference between the angle of the arms and that vector the more of the force gets transferred to the shocks, and therefore more squat.
Good video. A very good tuning option that also gets overlooked quite a bit. Especially for newer drivers/racers. I usually don't adjust mine. I'll set it once during the build and its usually good to go depending on if I'm building for the one carpet or the 3-4 clay tracks here. Generally I'll go between the lowest to only as high as 2 ° I found with my Serpent 2wd cars, they liked the squat at 0.5° on both carpet and clay.
Great info buddy… would be awesome if you put all your tuning videos into a playlist!
They are ;) Look under "setup tutorials"
very well explained. thank you.
Actually you're almost on the opposite side of how anti squat affects the forward bite, as far back as when the old gold pan RC-10 first came out the factory guys (Jay Halsey) said to improve the forward bite by placing around a .040 shim (I use one of the aluminum spacer washers for the body mount posts) between the front of the chassis plate and the front of the rear arm mounting blocks. I have always just cut out a slot in the aluminum washer I use and slide it in place over the mounting screw so it is between the tub and the arm mounts. The only thing I have ran into is with too much anti squat it can lift hard enough on the back of the car to actually extend the shocks to full extension and make the car start to "pogo" off the shocks because they are now just like a solid mount. Think of anti squat as pushing down on the rear tires actually increasing forward bite by pushing the tires down into the track surface, I have found that even though mechanically it doesn't physically add side bite it can do a very good job of doing so because if you toss it into a corner a little on the hard side by jumping on the power it adds enough instant forward bite to instantly stop the slide. If you watch a dirt modified or late model you can see the effects of a ton of anti squat and the instant forward bite it gives the car by how it forces the rear of the car to lift and that pushes the rear tires harder into the track surface. A lot of people don't understand that is what's happening and think when the rear of the car lifts that it's lifting the tires also and takes away the bite. But you can do an easy demonstration by putting a length of stiff wire or a strong piece of tubing so it sits on top of a rear a arm and under the chassis in front of the rear arm mounting blocks, the closer you can get to the center of the wheelbase the better. Now using that length of what ever you could find push down towards the ground and lift the front of the chassis up, did you notice what that did to the rear tires and the side effect of what happened to the rear shocks? You should have seen the tires develop a flatter contact area to the ground and it made the rear shocks extend further. THAT is what anti squat does for the rear bite it's like adding a couple of pounds of weight right over the rear tires and unlike a force that causes the rear of the car to rotate around the center of the rear axles causing the front of the car to lift up and the rear to squat down like the old drag cars did doing a wheelstand you aren't wasting torque and power trying to make the rear gears climb over each other using a lot of power and NOT making good use of it. Just search for adjusting four link rear suspension and using a torque arm fifth spring setup to increase bite on a dirt track race be it a modified or a late model, even better find a video on UA-cam
On UA-cam of the rear suspension working while on the track to see physically how it works and you can see for yourself.
I crank anti squat to 4deg or max on my ae b4.1 t4.2 & 22t4.0 for more traction and straight line stability on very loose low bite surfaces. Way better control and grip then 1.5deg. Learned this from Schumacher manuals that have the best tuneup advise lv come across.
Thanks for the vid, helped a lot
your tuning videos are by far the best on Y.T. thanks for sharing your thoughts.. and p.s. who ever gave this vid a dis like should be whipped repetedly..lol thanks again renoldo..
Haha. Glad you like it ;)
Low grip - low anti squat but how low? Less angle means front of arms lower than rear of arms?
What happen if i use negative anti squat? -1° to -3°. Will it be anti lift instead?
Yeah, I suppose that would keep the car more level under breaking. So a negative anti-squat in the rear is a bit like a positive anti-dive in the front.
You got your anti -squat and pro-squat angles backwards on the rear.
Very useful, thanks!!
Thanks for the video!
Not sure if this relates to the video but I'm finding my 4wd buggy is going wheelies at times after a wall ride at my indoor track. It's high traction, I've set it to a loose slipper and once I get on full trigger coming from the wall... It's there where it can wheel... Do you think it's a matter of reducing punch. I have an esc that controls two levels of punch...
Buggy is fine elsewhere on the track
+ayske1 My B44 would do that if I ran open cell foams and if I hit a bump. The front would kick up and the rear tires would expand and make the care wheelie on the straight. It was hella fun, but hard to drive. In your case, if the track is high grip, you may simply have too much stiffness in the rear suspension. Springs, pistons, oil, anti-squat, shock angle. Try the simpler things first, like standing the shocks up more, then anti-squat, and then springs/oil/pistons.
+doctormosfet I think you may be right... I'll try softer springs as I think since putting the hardest ones its started to wheel more.
@1:02, your description is exactly the opposite of what XRay setup helper says. Less anti-squat is better for a bumpy track. More anti-squat is more suited for smooth high grip tracks.
There are a few ways to look at this. On bumpy tracks, the bumps push against the arm. More anti-squat allows the bump to push against the arm at a shallower angle and cause the suspension to compress more, essentially causing the tires to skid less over the bumps, thereby giving you more trip (or causing you to lose less grip). However, if other parts of the same track are smooth but low grip, more anti-squat will hurt you there, as it's essentially acting like a stiffer rear spring on a loose surface. So whether to run more anti-squat on a bumpy track really depends on how much of the track is bumpy, in combination with how grippy or loose the surface itself is. On smooth, low grip tracks, less anti-squat is generally the way to go, as it allows the suspension to give more and therefore reduce how much the rear tires break traction. On smooth, high grip tracks, more anti-squat is better, as you already have the rear grip from the track surface and so you can use anti-squat to avoid excessive rearward weight transfer and give you more on-power steering.
@@doctormosfet Don't mean to attack, but your response mixes different scenarios and so it becomes a "depends." With more anti-squat, rear suspension compresses less and less camber change, therefore more contact patch during acceleration, which means higher *forward* traction. Car is also bouncier with more anti-squat because geometry is stiffened, which means less conducive to bumpy surfaces. Knowing the basic facts, one can then use judgement and experience to tune the car based on the track condition.
I've had situations where I wasn't sure whether to use more or less anti-squat, because the track had a mix of what could justify either case. There is a science to it, which is why "it depends," but ultimately judgment is informed by experience, which in turn is informed by experimenting with these things.
@@ihcnehc there's no real answer that's why, everything is balancing and the goal is to secure the benefits of a type of adjustment by finding the range where it is present. Perhaps a little antisquat will help decrease weight transfer for better turning but too much added and you would begin to feel the effects of less rear grip and they would outweigh the benefit increased steering gave.
@@rcbuggies57 Thanks for your feedback. Mechanically, raising anti-squad also raises roll center, essentially stiffens your rear suspension geometry. As a result, the rear end dips less when car is on power ( thus less F -->B weight transfer ) and rolls less when turning and "pops" a little more when jumping.
I thought doctormosfet's "There are a few ways to look at this..." comment from the 4th sentence on was spot on. Prior to that, I am not sure if he was referring to a genuinely bumpy surface or some artificial bumpy rhythm section.
I followed you for a bit but by the end of the video l was more confused about anti squat than ever
its because he's full of shit
So for drag racing would you want to run more anti squat?
on a higher grip surface, yes
@@doctormosfet thank you I appreciate the help.
Info is great , please put the camera on a tripod or something,