Rear brake conversion?

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StuBaker
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Re: Rear brake conversion?

Post by StuBaker » Wed Feb 05, 2020 8:48 pm

Thanks for that info. The Hoyle set up does look good though.
I'll put that in the 'hard to do bin'

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StewbieC
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Re: Rear brake conversion?

Post by StewbieC » Thu Feb 06, 2020 10:25 am

Frank289 wrote:
Tue Feb 04, 2020 9:15 pm
That means when i would order a upgrade from amstrongs to normal suspension from for example Gerry, there is no difference?
Not sure if you are just referring to replacing rear lever arm dampers with telescopic shocks. If you have a Hawk it is just bolt on as mounts are present for both. It makes some difference but not a massive deal. MGB rear axle to IRS swap is a big difference.
On the plus side - no banging and crashing (hallelujah!), No axle tramping (despite panhard rod and anti tramp bars on MGB) much nicer ride, ability to adjust ride height easier, Camber adjustment. Handling is night and day, trust me!
Negative points - Diff whine (as it is attached to the chassis)
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monster7
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Re: Rear brake conversion?

Post by monster7 » Thu Feb 06, 2020 11:43 am

The question here is: why?
Brake performance is good enough for any street application, and some clever set service openings will make live easier.
In addition, the "moving" weight is less.
I would rather think about to change the disks for vented once...

Frank289
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Joined: Sun Nov 13, 2016 8:12 pm

Re: Rear brake conversion?

Post by Frank289 » Thu Feb 06, 2020 4:37 pm

StewbieC wrote:
Thu Feb 06, 2020 10:25 am
Frank289 wrote:
Tue Feb 04, 2020 9:15 pm
That means when i would order a upgrade from amstrongs to normal suspension from for example Gerry, there is no difference?
Not sure if you are just referring to replacing rear lever arm dampers with telescopic shocks. If you have a Hawk it is just bolt on as mounts are present for both. It makes some difference but not a massive deal. MGB rear axle to IRS swap is a big difference.
On the plus side - no banging and crashing (hallelujah!), No axle tramping (despite panhard rod and anti tramp bars on MGB) much nicer ride, ability to adjust ride height easier, Camber adjustment. Handling is night and day, trust me!
Negative points - Diff whine (as it is attached to the chassis)
Jest im talking about replacing the rear arm dampers with telescopic ones. its a BRA with Mgb GT axle. dront disc brakes wilwood, so i guess the front brakes will do nicely but the backbreaks will ot be enough??

Ferngar
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Re: Rear brake conversion?

Post by Ferngar » Fri Feb 07, 2020 10:22 am

monster7 wrote:
Thu Feb 06, 2020 11:43 am
The question here is: why?
Brake performance is good enough for any street application, and some clever set service openings will make live easier.
In addition, the "moving" weight is less.
I would rather think about to change the disks for vented once...
So if the brakes are good enough why do you suggest going to vented discs?

peterc
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Re: Rear brake conversion?

Post by peterc » Sun Feb 09, 2020 9:45 am

The normal problem is the rear brakes locking up before the fronts. Most people especially with a Jag rear find the balance bar heavily biased to the front to compensate. With Willwood fronts and MGB rear drums I wouldn’t have thought you would have an issue depending of course on the size of the Willwoods. I know one or two members have in the past conjured up rear discs for the MGB axle.
I guess telescopic dampers are more efficient than the lever arms. I’m sure Gerry can sell you the correct parts to bolt on.
To be closer to the original car then having independent rear suspension is probably better as Stewbie has related above.
The prototype Cobras did have inboard rear discs so that gives me a get out to not bother with an outboard conversion. Besides outboard discs have more unsuspended load.
I would have preferred to save some weight over the rear axle by using the Hoyle set up but Gerry refused to sell me the parts.
The Jag rear is rather heavy so with my Rover engine I get a weight bias to the rear. 46:54%
Peter C

Frank289
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Re: Rear brake conversion?

Post by Frank289 » Sun Feb 09, 2020 1:47 pm

Thank u Peter, I have a TVR 4,3 ltr engine so, light weight like yours too. i heared and did read so many negative about lever arms. that im not even going to try it and right away rebuild it with something from Gerry. I still have to make some changes on the Willwoods because they are not street legal at. have to see what hasto be changed. bought them new 3 years ago in one buy with the MGB axles. the seller didnt know what he sold. i hope to start finishing my cobra this year again . Thats why i start informing now. Thx for the info

monster7
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Re: Rear brake conversion?

Post by monster7 » Wed Feb 12, 2020 3:29 pm

Ferngar wrote:
Fri Feb 07, 2020 10:22 am
monster7 wrote:
Thu Feb 06, 2020 11:43 am
The question here is: why?
Brake performance is good enough for any street application, and some clever set service openings will make live easier.
In addition, the "moving" weight is less.
I would rather think about to change the disks for vented once...
So if the brakes are good enough why do you suggest going to vented discs?
I ment vented disks instead of outboard system for "tracking" application. This solves the cooling issue without having more unsuspended load. Additionally, you can find easily disks from other suppliers which will fit. However, this setup need adapters as well...

CobStang
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Re: Rear brake conversion?

Post by CobStang » Wed Feb 12, 2020 11:13 pm

peterc wrote:
Sun Feb 09, 2020 9:45 am
The normal problem is the rear brakes locking up before the fronts. Most people especially with a Jag rear find the balance bar heavily biased to the front to compensate. With Willwood fronts and MGB rear drums I wouldn’t have thought you would have an issue depending of course on the size of the Willwoods. I know one or two members have in the past conjured up rear discs for the MGB axle.
I guess telescopic dampers are more efficient than the lever arms. I’m sure Gerry can sell you the correct parts to bolt on.
To be closer to the original car then having independent rear suspension is probably better as Stewbie has related above.
The prototype Cobras did have inboard rear discs so that gives me a get out to not bother with an outboard conversion. Besides outboard discs have more unsuspended load.
I would have preferred to save some weight over the rear axle by using the Hoyle set up but Gerry refused to sell me the parts.
The Jag rear is rather heavy so with my Rover engine I get a weight bias to the rear. 46:54%
Peter C
I have made and installed a rear disc conversion to my MGB rear axle. I did it more for looks than performance, as the stock drums with decent linings are very effective.
Anyway I had to install a proportioning valve to turn down the rears :roll:
The BRA I have is also on coil overs all round, has a four linked rear axle, double wishbone front, and not a Hawk / Hoyle part in sight.

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