Hubs are free?
- Thread starter Jeffyoung
- Start date
Tom Broring
Well-known member
Jeff, for rear wheel drive there is no blanket allowance to change front hubs when you already have a separate rotor and hub like the Triumph. In addition, you cannot modify or replace the bearing carrier portion of the strut assembly when the strut and carrier are a one-piece assembly like yours. You can only modify the strut to allow different strut inserts/springs and some reinforcement.
The original limited prep rules listed the front hubs as unrestricted but that was changed when the rules were rewritten several years ago. That said, a vehicle specific allowance can be requested if there is a history of failures.
The original limited prep rules listed the front hubs as unrestricted but that was changed when the rules were rewritten several years ago. That said, a vehicle specific allowance can be requested if there is a history of failures.
This is in the Drive Train Level 2 Prep rules:
Axle shafts, bearings, bearing carriers, hubs, and universal
joints/CV joints are unrestricted.
So that means FWD cars can change hubs, and RWD cars can change rear "hubs" (if IRS), but RWD cars can't change front hubs??
That doesn't make much sense.
Axle shafts, bearings, bearing carriers, hubs, and universal
joints/CV joints are unrestricted.
So that means FWD cars can change hubs, and RWD cars can change rear "hubs" (if IRS), but RWD cars can't change front hubs??
That doesn't make much sense.
Rule is the rule, but even on teh ITS car I kill hubs ever three or four weekends. Too small a bearing. Too much stress on it, eventually it distorts the hub I think and has too much play in it.
There are a few older RWD cars with similar problems with the front wheel bearing being too small (mine is litrerally maybe silver dollar size).
Odd rule, but rules are rules.
There are a few older RWD cars with similar problems with the front wheel bearing being too small (mine is litrerally maybe silver dollar size).
Odd rule, but rules are rules.
Ron Bartell
Well-known member
Rules are rules but sometimes a special dispensation is required. If I follow your posts you are building a TR8. Well the Brits being the Brits they would have fixed that small front bearing problem on later models and you would have been allowed to run that without a problem. Since there weren't very many years that they made the TR8 they never upgraded it so it is a weak spot that might warrant a letter to the CRB asking for an alternate front hub for that car. Changing hubs every three or four races is not right.
Not sure what you mean. The hub has an inner and outer bearing, separated by a maybe 1/2 solid piece of metal hub. So yes, there is a spacer between the two bearings (teh inner is quite a bit larger).
A spacer just on the outer would make things worse, slightly - would push the hub out on the stub axle and increase the forces on it -- longer lever arm.
A spacer just on the outer would make things worse, slightly - would push the hub out on the stub axle and increase the forces on it -- longer lever arm.
Protech Racing
Well-known member
Some Brit cars have a solid spacer( with shims) between the races to set end play and the nut is torqued to 50# or so, while most have the end play set the US way with nut torq set at 4# minus a flat.
Some old Mazdas use a spacer/ shim also.
I doubt that one or the other would have any load tolerance benefit . The only advantage that I can think of with the spacer is that the races stay fixed to the hub better.
I would suggest letter to move that line from drivetrain to " Suspension and steering"
I dont see how it would be considered speed creep as any replacement parts would be heavier /slower. That may dominoe into the spindle zone tho. The rules clearly want to maintain the stock relationship of the spindle to steering link.IMHO
Some old Mazdas use a spacer/ shim also.
I doubt that one or the other would have any load tolerance benefit . The only advantage that I can think of with the spacer is that the races stay fixed to the hub better.
I would suggest letter to move that line from drivetrain to " Suspension and steering"
I dont see how it would be considered speed creep as any replacement parts would be heavier /slower. That may dominoe into the spindle zone tho. The rules clearly want to maintain the stock relationship of the spindle to steering link.IMHO
R. J. Sorensen
Well-known member
I believe the purpose of the LBC spacer was to pre-stress the stub axle by stretching it to a predetermined load.
Can't see how this would help extend the life of the hub.
RJS
Can't see how this would help extend the life of the hub.
RJS
Spacer properly fitted will help hub last.
If the stub axle flexes bearings are stressed and hubs get distorted.
also make sure the proper bearings are fitted that have the proper radius at the inner
seat to hub/stub axle.
TR8 is very under braked so every effort needs to be made to reduce heat transfer
into the hub.
I would also cryo and rem the hubs and ensure the race machining is true and the proper size.
Read up on the rally cars B.L. campaigned, Bill Price book is a good starting point.
If the stub axle flexes bearings are stressed and hubs get distorted.
also make sure the proper bearings are fitted that have the proper radius at the inner
seat to hub/stub axle.
TR8 is very under braked so every effort needs to be made to reduce heat transfer
into the hub.
I would also cryo and rem the hubs and ensure the race machining is true and the proper size.
Read up on the rally cars B.L. campaigned, Bill Price book is a good starting point.
Tom Broring
Well-known member
Protech Racing":1vbcik64 said:
The preloaded spacer type of tapered bearing setup like the MGB used more evenly spreads bearing load against the inner and outer races rather than the load shifting so much depending on cornering load. Vintage racers with TR4/250/6 often do this mod with good results.
Mike, would a lightweight aluminum alloy hub (unsprung weight) be a performance advantage/speed creep? I really think this is an area where a blanket update should be considered. It is no fun racing next to someone whose hub or spindle fails. I am pretty sure that many Spridgets run modified spindles that do not meet the letter of the rule, but would anyone protest that to a fellow racer? The problem is how far should this area be opened up.
I did write a letter asking for improved alloy spindles for my Spit a few years ago and suggested this would benefit all classifications but only a line allowance was granted for the Spitfiire.
I've been running, successfully, this car in ITS for a LONG time (lots of race wins, 2011 SARRC championship, lots of satisfactin beating Miatas, RX7s, BMWs, Acuras, etc). I know the brakes are weak, although I think at 2600 lbs in E Prod with vented rotors up front and discs in the rear I'll be ok. My solution in ITS was a titanium shim behind the pad, wheel fans attached to a wheel spacer, ducts as cllose to the centerline of the nose as possible and good rotor hats, plus always use Castrol SRF. Eventually I got it to work even at a place like CMP.
But I digress. ON the hubs, there are alloy hubs available with a bigger bearing (and the stock ones with a bigger bearing as well), all of which is it seems illegal at this point in time. Lightweight ally hubs would save me about 3 lbs per corner, or 6 total, but it is unsprung, and would dissipate break heat better. So I can't say they aren't a performance advantage.
That said, with the power upgrade in E PRod, which I think will be substantial over the 190 hp I make at the wheels now, I am concerned about cornering and braking forces on the hubs and bearings. The stock outer bearing is, no lie I'm holding one now, no bigger than a silver dollar.
I hate to write in without running the car so I'll probably wait but yeah, still don't get he rule on this one.
But I digress. ON the hubs, there are alloy hubs available with a bigger bearing (and the stock ones with a bigger bearing as well), all of which is it seems illegal at this point in time. Lightweight ally hubs would save me about 3 lbs per corner, or 6 total, but it is unsprung, and would dissipate break heat better. So I can't say they aren't a performance advantage.
That said, with the power upgrade in E PRod, which I think will be substantial over the 190 hp I make at the wheels now, I am concerned about cornering and braking forces on the hubs and bearings. The stock outer bearing is, no lie I'm holding one now, no bigger than a silver dollar.
I hate to write in without running the car so I'll probably wait but yeah, still don't get he rule on this one.