Anybody used the LN Roller bearing IMS bearing?

[Nine8Six]

Originally Posted by SilverSSS

I tend to favor a roller bearing for this swap, has anybody here successfully used the LN Roller bearing Replacement bearing for their IM S upgrade? Any issues?

Favoring one for another; a scientific reasoning should still be an influence factor in your decision (brand/makes aside). If your car never rev pass the range of an F1 car, you might as well be better with a roller long term. The ball bearing type however seems to be the trade off and best of both worlds.

Still today nobody have been able to output centrifugal force data on the shaft itself so hard (near impossible) to say which is better. If it be me I'd stick with what Porsche says

Roller bearings are a type of bearing that use rolling elements to support loads and reduce friction. As opposed to ball bearings, roller bearings have barrel-shaped rolling elements instead of spherical balls. They are capable of supporting heavier loads than similarly sized ball bearings but cannot handle as high of speeds as ball bearings.

[JFP in PA]

Originally Posted by Nine8Six

Favoring one for another; a scientific reasoning should still be an influence factor in your decision (brand/makes aside). If your car never rev pass the range of an F1 car, you might as well be better with a roller long term. The ball bearing type however seems to be the trade off and best of both worlds.

Still today nobody have been able to output centrifugal force data on the shaft itself so hard (near impossible) to say which is better. If it be me I'd stick with what Porsche says

Roller bearings are a type of bearing that use rolling elements to support loads and reduce friction. As opposed to ball bearings, roller bearings have barrel-shaped rolling elements instead of spherical balls. They are capable of supporting heavier loads than similarly sized ball bearings but cannot handle as high of speeds as ball bearings.

A far larger factor than RPM is the harmonics of the shaft itself; most IMS retrofits still allow, or even encourage, oil intrusion into the shaft, which can set up strange vibrations as the shaft, now partially full of oil, accelerates under load; none of which is doing the rear bearing any good.

[Nine8Six]

Originally Posted by JFP in PA

A far larger factor than RPM is the harmonics of the shaft itself; most IMS retrofits still allow, or even encourage, oil intrusion into the shaft, which can set up strange vibrations as the shaft, now partially full of oil, accelerates under load; none of which is doing the rear bearing any good.

I know, makes you really wonder if the kit got balanced in that Finland backshop before each installations lolll That should have taken care of the harmonics at best.

Was just sayin RPM, often the easiest decision benchmark when CAE data is out of reach. Old formulas. Tons of engineer calculators available online that will let anyone know how much you'll be able to rev up that little sport car during those spirit drives (roller vs balls, etc). Not a taboo thing

MicroPoly - Maximum RPM Calculator

(J - why builders want rollers? any specific reason(s) to this?)

[JFP in PA]

Originally Posted by Nine8Six

I know, makes you really wonder if the kit got balanced in that Finland backshop before each installations lolll That should have taken care of the harmonics at best.

Was just sayin RPM, often the easiest decision benchmark when CAE data is out of reach. Old formulas. Tons of engineer calculators available online that will let anyone know how much you'll be able to rev up that little sport car during those spirit drives (roller vs balls, etc). Not a taboo thing

MicroPoly - Maximum RPM Calculator

(J - why builders want rollers? any specific reason(s) to this?)

They advertise "superior thrust control", which makes no sense because the shaft uses the IMS rear flange as a rear thrust bearing, and even the factory IMS bearing uses the center bolt to limit forward thrust.

We have pulled a lot of OEM bearings, and not once have seen evidence of excessive thrust loading.

[Nine8Six]

huh? Completely lost now man. Roller bearings have nothing to do with 'thrust', I'll check again but last time I did it wasn't lolll I would have expected the use of the roller bearing to defeat any great centrifugal force/load that the shaft could have made. Interesting....

Thrust? as in gravity pull under accel? momentum (kg.m/s)? data based on what exactly? If you know. Not that I care to know, just curious

[78F350]

Originally Posted by Nine8Six

huh? Completely lost now man. Roller bearings have nothing to do with 'thrust', I'll check again but last time I did it wasn't lolll I would have expected the use of the roller bearing to defeat any great centrifugal force/load that the shaft could have made. Interesting....

Thrust? as in gravity pull under accel? momentum (kg.m/s)? data based on what exactly? If you know. Not that I care to know, just curious

I'm no engineer, but in this reference I think that "thrust" is referring to motion perpendicular to the axis of rotation.


I would not expect a lot of force in that direction on the IMS, but a slight oscillation at high RPM over time could wear a roller style much more than a spherical ball. ...?

[JFP in PA]

Originally Posted by 78F350

I'm no engineer, but in this reference I think that "thrust" is referring to motion perpendicular to the axis of rotation.


I would not expect a lot of force in that direction on the IMS, but a slight oscillation at high RPM over time could wear a roller style much more than a spherical ball. ...?

You are correct in your assumption about thrust.

[Nine8Six]

Originally Posted by 78F350

I'm no engineer, but in this reference I think that "thrust" is referring to motion perpendicular to the axis of rotation.

Oh your dead right, thrust it is. Perfect illustration

Put thrust load on that roller bearing in your picture and it will immediately fail. Not after a few rotations, I mean immediately fail as "it just won't spin anymore".

hence why I was confused with JFP's thrust explanation. In fact, I'm convinced its a spelling mistake he didn't bother to correct. Or perhaps he's trying to make fun of the IMS business-goin'on thing situation. I don't know man.

If indeed that IMS shaft suddenly requires both thrust and load management then one needs a bloody angular bearing on that axis. Beside these sort of shaft design are rare as hell, they are terrible design in fact and are avoided as much as possible. Porsche?!