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Fps Or Ball Diff

Fps Or Ball Diff

Old 06-17-2003, 08:16 AM
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xax
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Default Fps Or Ball Diff

Wanna change the rear diff for my impulse due to worn gears but dom't know which is a better choice Ball diff or FPS?CAn anyone help ?Thanks.
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Old 06-17-2003, 08:31 AM
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Default Re: Fps Or Ball Diff

Originally posted by xax
Wanna change the rear diff for my impulse due to worn gears but dom't know which is a better choice Ball diff or FPS?CAn anyone help ?Thanks.
If u can afford the FPS, by all mean, get the FPS. I never change back to ball diff after using the FPS. Super smooth rotation that it takes longer to re-built it compare to Ball Diff.

If you worried about slight increase in weight on your car, then get the Ball Diff.

If u want to save some money, then just replace the worn out gears.
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Old 06-17-2003, 08:32 AM
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I have the reg. ball diff (the one with the spring steel outdrives)in my impulse and love it. I have never owned the FPS diff, but i know it is better. I'm pretty sure it has a slipper in it. So, if the diff begins to slip, it will not hurt the balls at all. Kind of like the nitro tc3 diff, but much, much, much beefier. I'm pretty sure the FPS diff only comes with the 47 tooth pulley, so you will have to purchase the 46 tooth pulley seperately.

The ball diffs are so easy to adjust, even while the car is running. All you have to do is slip a hex key in one outdrive ank turn the right wheel.

Try Winner's Circle for the diffs at gasrccar.com or 1-866-NITRORC. Lee Muse has a great thing going for serpent parts.
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Old 06-17-2003, 08:51 AM
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Originally posted by Proficar403
I have the reg. ball diff (the one with the spring steel outdrives)in my impulse and love it. I have never owned the FPS diff, but i know it is better. I'm pretty sure it has a slipper in it. So, if the diff begins to slip, it will not hurt the balls at all. Kind of like the nitro tc3 diff, but much, much, much beefier. I'm pretty sure the FPS diff only comes with the 47 tooth pulley, so you will have to purchase the 46 tooth pulley seperately.

The ball diffs are so easy to adjust, even while the car is running. All you have to do is slip a hex key in one outdrive ank turn the right wheel.

Try Winner's Circle for the diffs at gasrccar.com or 1-866-NITRORC. Lee Muse has a great thing going for serpent parts.
The FPS doesn't come with any pulley at all, sold separately. I've still not taking it out for re-built from the last 3 months. Unlike my ball, i've to re-built due to sand easily get into the ball and the plate.
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Old 06-17-2003, 09:14 AM
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Originally posted by nizee
The FPS doesn't come with any pulley at all, sold separately. I've still not taking it out for re-built from the last 3 months. Unlike my ball, i've to re-built due to sand easily get into the ball and the plate.
Yup, I have not rebuilt my FPS diff in my Impulse either. It is impossible for sand to enter the FPS unlike the regular ball diff.

Yes, the ball diff is lighter. Proficar mentioned that you can adjust it "externally" but still you need to take out the left rear dog bone... You need to dismantle the rear left shock and detach the upper left rear arm to the left rear knuckles to pop out the dogbone.

Unlike the FPS diff, the diff action in the ball diff will somewhat be inconsistant in a long main when the bearings start to wear out (if they wear out). The FPS diff provides constant diff action throughout the entire race as there is actually no wearing parts. It's also easy and fast if you need to adjust the rear diff settings.

With the FPS, you just need to loosen the grub screw that locks the nut and unscrew or tighten this nut to provide less or more friction for diff action. You can see in the picture attached that the diff action is somewhat provided by 2 pieces of rubber pads externally. So there is actually no wearing of parts like the bearings or thrust plates and such on the normal ball diff.
Attached Thumbnails Fps Or Ball Diff-fps_diff.jpg  

Last edited by InitialD; 06-17-2003 at 10:25 AM.
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Old 06-17-2003, 09:32 AM
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Originally posted by InitialD
Yup, I have not rebuilt my FPS diff in my Impulse either. It is impossible for sand to enter the FPS unlike the regular ball diff.

Yes, the ball diff is lighter. Proficar mentioned that you can adjust it "externally" but still you need to take out the left rear dog bone... You need to dismantle the rear left shock and detach the upper left rear arm to the left rear knuckles to pop out the dogbone.

Unlike the normal ball diff, the diff action will somewhat be inconsistant in a long main when the bearings start to wear out (if they wear out). The FPS diff provides constant diff action throughout the entire race as there is actually no wearing parts. It's also easy and fast if you need to adjust th rear diff settings.

With the FPS, you just need to loosen the grub screw that locks the nut and unscrew or tighten this nut to provide less or more friction for diff action. You can see in the picture attached that the diff action is somewhat provided by 2 pieces of rubber pads externally. So there is actually no wearing of parts like the bearings or thrust plates and such on the normal ball diff.
Your frame kinda looks like mine....
Waiting for Modeller on the new set of frame... then my car looks new..
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Old 06-17-2003, 10:23 AM
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Originally posted by nizee
Your frame kinda looks like mine....
Waiting for Modeller on the new set of frame... then my car looks new..
I know what you mean That reminds me... I need to ask those guys who would be interested in modellor's chassis

I took a second look at the pic and the digicam really captured all the scratches

Well, the pic you see is actually the chassis from the Wolfpack for the Impulse PRO as the FPS is still in that car.
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Old 06-17-2003, 10:33 AM
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Default New Ball Diff?

Hey guys,

Question- I believe I was reading somewhere in MYTSN,
Serpent was going to redesign there balldiff and
make it externally adjustable, without disassembly
of one side of the car.
Can anyone else concur with this......
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Old 06-17-2003, 10:39 AM
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Default Re: New Ball Diff?

Originally posted by BSYDOR
Hey guys,

Question- I believe I was reading somewhere in MYTSN,
Serpent was going to redesign there balldiff and
make it externally adjustable, without disassembly
of one side of the car.
Can anyone else concur with this......
Yes, I actually forgot about that one... Thanks for reminding. This has been the rumour and is somewhat confirmed by the factory people as well and the last thing that was mentioned about it is that it is still under testing phase. When it will come out, we do not know exactly. Best is to stay tuned to mytsn. But surely, it is in the works.
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Old 06-17-2003, 02:12 PM
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I think you all are mistaken. The reg ball diff is externally adjustable. If you look at a pic of it, it has a hole in the left outdrive that can be accessed by a hex key. This locks the diff adjustment screw, so all you have to do is turn the right wheel to tighten or loosen the diff. See the pic in the link.
http://www.mytsn.com/products/desc.asp?prid=2227
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Old 06-17-2003, 02:49 PM
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The ball diff has a grub screw in the right outdrive that once tighned down you cannot adjust it without taking the right bone out and loosening it.
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Old 06-17-2003, 05:59 PM
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Originally posted by Proficar403
I think you all are mistaken. The reg ball diff is externally adjustable. If you look at a pic of it, it has a hole in the left outdrive that can be accessed by a hex key. This locks the diff adjustment screw, so all you have to do is turn the right wheel to tighten or loosen the diff. See the pic in the link.
http://www.mytsn.com/products/desc.asp?prid=2227
Proficar, TAW is correct on this one. Once the set screw in the outdrive locks in, you cannot tighten or loosen the diff by the method outlined above. I once did what you mentioned and thought that the ball diff was really externally adjustable... Somehow I managed to change the settings BUT then the next thing I know is that the car looses rear drive because the diffs will be slipping. The reason for this is the set screw will turn loose. Every time you change the diff setting, the set screw needs to be loosened and once the diff is set, the set screw needs to be tightened back to lock the diff setting in place.
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Old 06-17-2003, 06:59 PM
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Originally posted by Proficar403
I think you all are mistaken. The reg ball diff is externally adjustable. If you look at a pic of it, it has a hole in the left outdrive that can be accessed by a hex key. This locks the diff adjustment screw, so all you have to do is turn the right wheel to tighten or loosen the diff. See the pic in the link.
http://www.mytsn.com/products/desc.asp?prid=2227
NO, we are not wrong, we own it so we know it. Once u loosen that method, the whole diff will be loose after a few laps, like what InitialD mention. You might also damage the tread for the grub screw doing that method.
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Old 06-18-2003, 06:35 AM
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Thanks guys you have been a great help.But can you guy elaborate the function of diff i.e what will happen to the car wif a tight diff and a loose diff?Is there a standard setting or set it according to indivvidual driving style?Thanks
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Old 06-18-2003, 07:16 AM
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You need to set it according to your driving style and preference. A tight rear diff will give you less off power steering but more on power steering. You will want to use a loose rear diff when there isn't enough traction on the track. A loose diff will enable you to turn faster into a corner but somewhat slower out of a corner. Vice versa for a tight rear diff i.e. slow in fast out.
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