<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto"><div dir="ltr"><meta http-equiv="content-type" content="text/html; charset=utf-8"><span style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%; background-color: rgb(255, 255, 255);">Hi all, </span><br style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%;"><span style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%; background-color: rgb(255, 255, 255);">I'm a long time Healey owner having had my BT7 for over 30 years.</span></div><div dir="ltr"><br></div><div dir="ltr"><span style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%; background-color: rgb(255, 255, 255);">Recently I had a complete failure of a brake front drum (photos below) on my 1956 Jensen 541 (a 4ltr Austin powered contemporary of the Healey) </span><span style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%; background-color: rgb(255, 255, 255);">resulting in a total loss of my brakes. </span><span style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%; background-color: rgb(255, 255, 255);">Not an experience I want to go through again. As a result I am looking to do a drum to disc conversion using predominantly Healey parts </span></div><div dir="ltr"><br style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%;"><span style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%; background-color: rgb(255, 255, 255);">My car uses several components in common with the BN1, in particular it uses the same king pin/swivel axle set up. I have pretty much go the parts needed for the conversion (Denis Welsh Heavy Duty swing axles, AH 3000 steel wheel BTC101 hubs, taper bearings, disks and hub adapters etc) but I have some concerns about what changes I might need to make to the rest of the hydraulic system, particularly what changes I will need to make (if any) to the master cylinder and rear wheel cylinders. </span><br style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%;"><br style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%;"><span style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%; background-color: rgb(255, 255, 255);">I was wondering what the list subscribers have done to the MC and rear wheel cylinders when you've converted the front drums to disks on your early cars. I believe that the front calipers need higher pressures (900psi) to operate than compared to the rear drums (400 psi) and was wondering if I need to fit some for of brake balance valve to stop the rears locking up before the fronts. Do you change the bore of the rear wheel cylinders when doing a conversion as an alternative? I have also read on the web that there may be a check valve in the MC which I might have to remove. Apparently with a drum brake set up the check valve retains some residual pressure after braking to prevent any air getting into the wheel cylinders, but with a disk brake set up this could cause brake drag. </span><br style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%;"><br style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%;"><span style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%; background-color: rgb(255, 255, 255);">I would hate to do the conversion only to have worse brakes than my twin trailing shoe front drums that I have now. </span><br style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%;"><br style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%;"><span style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%; background-color: rgb(255, 255, 255);">Currently I have two 5/8" wheel cylinders on the rear, four 1 1/4" wheel cylinders on the front and a 3/4" master cylinder with a pretty small reservoir. The system also incorporates a Lockheed 3:1 brake servo. </span><br style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%;"><br style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%;"><span style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%; background-color: rgb(255, 255, 255);">Any advice would be appreciated. </span><br style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%;"><br style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%;"><span style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%; background-color: rgb(255, 255, 255);">Phil</span><div dir="ltr"></div></div><div dir="ltr"><span style="font-family: Arial, Helvetica; font-size: 13px; -webkit-text-size-adjust: 100%; background-color: rgb(255, 255, 255);"><br></span></div><div dir="ltr"><a href="https://joc.org.uk/jensen-models/541-series/">https://joc.org.uk/jensen-models/541-series/</a></div></body></html>