So work has been progressing on the TR6 Hunter Roadster.
Because I'm going to need a new driveshaft made with the transmission, I decided that now would also be the best time to do the Goodparts R200 differential swap, because that also requires changing the driveshaft.
First step was removing the old diff.
With the differential out, I pulled out the original driveshaft. Unfortunately, I had thought that the flange was the same for the output of the TR6 4 speed and the BW65, but they're actually slightly different. I'm probably going to have to provide my spare flange when I get the driveshaft made, because while I know the TR6 U-joint flange end is an off the shelf part, I'm not sure if theyr'e still making the other flange end that I need for the BW65 output flange.
I got myself a nissan R200 from an Infinity Q45 with a 3.54:1 ratio, a bit better for highway driving and lower RP with the automatic, since I'll no longer have the 5spd and I cant put an overdrive in it
Here's the rest of the goodparts kit
The rear axles that I am using on this, since my originals needed rebuilding, I got from Al Gary when I bought his engine, and he had the R200 kit in his car already, so I didnt need to modify the axles any. I plan in the future to get a set of the CV axles from goodparts, but right now I just want to get on the road as soon as possible =)
The kit installs on the differential wicked easily, making this a true bolt-in conversion, if you source the differential from goodparts with the flange work and grinding already done.
I had forgotten that when I put the differential on the last time that I had no body on the frame, and so thought that I could get the differential out with the exhaust still attached. Trying to drop the differential and having it catch on the exhaust pipe and twist, just about coming off my jack sideways and ripping the fuel line off the frame quickly debased me of that idea! A few hours later and a bit of elbowgrease and I had the old differential out, the new one installed.
Something which I will be doing in the future, but probably not until everything else is finished, is making extra brackets for the rear suspension. I'm using the Moss motors rear tube shock conversion, and with the Hathaway Hunter body, the rear body/bumper bracket mount points are unused. One of the weaknesses of the Moss kit is excessive front and back motion breaking the welds of the rear differential crossmember. This illustration shows where I will be making a bolt-in bracket to attach the Moss bracket to the rear mounting points.
Right now there are just a couple of bolts holding the HVDA 5 speed in place, but they're positioned such that I cant get both sides of the bolt at once by myself, and it's getting quite frustrating! I think that I need to wait until I can get someone over to my house to help before I get the last few bolts out and remove the current transmission. Once that is done the next step is to test-fit the BW65 and take all the measurements needed to fabricate a new rear-mount for the transmission, and to measure the exact length from flange face to flange face for the new driveshaft. My goal is to order the driveshaft on monday (probably from Richard Good again, his service is great) and send him my extra bw65 output flange.
Once I've fabricated the brackets to hold the transmission, I'll get started figuring out the right order to bolt together the bushings and mount up the flexplate. Orignially I was going to swap the rear-engine plate with the triumph 2500TC automatic rear plate that I have, but I think the only actual difference is a single hole for a socket wrench to access the flex-plate to torque converter bolts, so I will just use a holesaw to cut the extra hole in the existing plate.
Because the BW65 is an automatic, it has a kickdown cable which needs to be attached to the throttle linkage. The current throttle linkage has no place to attach the cable. However, because I need to remove the pedal box and re-do it with fewer pedals and different spacing. Rather than fabricating a new linkage and doing the math to figure out the right throw for the kickdown cable, etc... The triumph TR7 throttle linkage and gas pedal is a cable-linkage which already has the extra mount for the kickdown cable, and is designed to work with dual stromberg 175CD, so the throw is correct too. Instead of playing around with angles and arc motions etc... i'm going to fabricate a bracket to mount a TR7 throttle linkage to the TR6 intake manifold and use a TR7 gas pedal, and call it a day, leaving only a brake pedal in the original pedal box.
Feels good to be making progress again! Been almost 2 years since the last major bit of work, and the time since then has all been trying to solve the "I'm too tall to drive this car" problem.