Roller SC drop gears
Turbo Mini Forums

I have been advised by MED that for a high power build (>130bhp) I should really use their Roller bearing sc drop gears instead of the normal pin type.

Is this REALLY necessary? for a ROAD build?

Apparently the idler bearings have a tendency to start to work their way out of the housing under very high load.

"If its not broke, whack a turbo on it"

https://www.youtube.com/c/turbominitv

Normal pin should be fine on SC drops as it reduces the side load on the shims anyway. As long as you replace the idle bearings and shim them correctly.

The roller type are easier to setup, but seem to be alot noisier on idle from my experience. There are great if the gearbox or transfer case as slight thrust damage. That's why we use them.

What engine are you building? Many on here have gone back to helical drops on SCCR boxes. For a road car SC Drops will start to really piss you off after about 5mins.

Edited by alaskanow0 on 4th Feb, 2016.

Class C 3rd Place Avon 2011 14.18 @101mph

never really seen a problem with the idler bearings personally.

Ok, just realised your doing YouTube build.

Class C 3rd Place Avon 2011 14.18 @101mph

Yep - so its a 1310, 10cc omegas, with "the head"

I do intend to use the car for some long-ish trips, not drag/track, so also think that the SC drops will start to get very much on my tits....

I MAY just build it with the old helicals for a start and see how it goes...

"If its not broke, whack a turbo on it"

https://www.youtube.com/c/turbominitv

What gearbox are you going to be running?

Class C 3rd Place Avon 2011 14.18 @101mph

Initially a standard one, but will be upgrading to SC as and when cash allows.

"If its not broke, whack a turbo on it"

https://www.youtube.com/c/turbominitv

There's evidence on Minispares of a helical cut roller idler gear for A+ gear case which uses the old cooper s tooth profile. They also do a matching primary gear with floating bush.

Not yet available!

the straight cut whine is the thing i miss the most about the a series

Yes i moved to the darkside

Instagram @jdm_brett

thats jolly interesting,

Personally the noise of SC drops has never really bothered me, but the helicals thrying to munch their way through the side of the casing has always seemed a bit shit... they clould have put in replacable bearing faces like the lay gear.

hmm.......... choices choices...!!!

Might invest in some normal SC's, not sure the extra £110 for the roller kit is warranted for a road build tbh.

Edited by Turbonator on 4th Feb, 2016.

"If its not broke, whack a turbo on it"

https://www.youtube.com/c/turbominitv

http://minispares.com/product/Classic/Engi....aspx|Back%20to

Had the roller s/c med drops in since 2011 no probs they are quiet on idle ...no clattering but definately a bit louder on the whine......ive just learnt to tune them out i suppose......switzerland,italy,kent,lithuania...etc

Edited by smokestack-lightning. on 6th Feb, 2016.

Double-Blind experiment, N:
An experiment in which the Chief Researcher believes he is
Fooling both the subject and the lab assistant. Often accompanied by
a belief in the Tooth Fairy.

Roller have a louder whine? I want some! The whinier the better imo

Helical drops all the way. Nothing like slipping it into fourth and crusing in relative silence

On 5th Feb, 2016 Sprocket said:
Helical drops all the way. Nothing like slipping it into fourth and crusing in relative silence

Yes i moved to the darkside

Instagram @jdm_brett

With helical drops, can you put dowels into the aluminium casings to pin the thrusts in place? So instead of the thrusts spinning and munching up the casing, the idler would spin against the thrust surface instead.

On 5th Feb, 2016 Brett said:

On 5th Feb, 2016 Sprocket said:
Helical drops all the way. Nothing like slipping it into fourth and crusing in relative silence

anyone building a weekend car that can cruse in relative silence needs a serious reality check !!

Edited by Sprocket on 5th Feb, 2016.

On 5th Feb, 2016 Sprocket said:

On 5th Feb, 2016 Brett said:

On 5th Feb, 2016 Sprocket said:
Helical drops all the way. Nothing like slipping it into fourth and crusing in relative silence

anyone building a weekend car that can cruse in relative silence needs a serious reality check !!

That's ok then code that car comes out during the week too.

Stealth is the key my young padawan learner

Yes i moved to the darkside

Instagram @jdm_brett