After two years the 36 Coupe is back on the road down under following a complete drivetrain rebuild and many other bits and pieces. It had its first outing last weekend with my brother using it to drive his daughter to her wedding. The 39 Box behind the 8BA is driving through what I think is the original Banjo but at 50 mph the engine is screaming, probably as it was meant to do back in 1936. I don't have a tacho on it but I suspect around 3500 - 4,000 rpm. I also want to fix the stance of the car a bit and get the rear end down a couple of inches and tuck the taller 255 tyres into the guards so the rear end is about to change and I'm looking to swap it for an open drive unit which will be based as much on width as any other factor but I also need to get the diff ratio right. At the other end I face the choice of changing the 39 Box to an open drive set up with the new closed rear mount and longer main drive shaft, or changing the box to a later F100 unit with the open drive but both options will require modification to the frame for the rear mount. Any advice on which of these options or others is more practical would be appreciated and can anyone point me to a thread or link that describes the modifications required, or maybe somebody makes a new piece to suit. One problem for me in Australia is access to the later model box which might end up driving my final decision. Suggestions would be appreciated View attachment 2761633
1. Where are you in Australia? 2. 255, is that a 15" radial? If so I'd be interested to know what wheels you have. 1936 cars had wide 5 wheels, so something is not stock. 3. So this rear end swap, I presume you are wanting to retain a Ford banjo? Or, does this not matter? If it doesn't matter, it would be easiest to mount a later diff of the required width on a parallel leaf kit. 4. A later 5 speed box with O.D. would be the best bet. A t-5 with a short s-10 extension would put the stick in close to stock location. You can get adapters for the engine. Some of the guys in Victoria use Toyota 5 speeds. Do a search for t-5's and flatheads, there are many threads about various aspects of the conversions and the boxes themselves. BTW the engine shouldn't be 'screaming' at 50 MPH.
X38, I think he said he wants to put the larger tyres under it... might still have the stock bits...??? As for the open drive option I've just had some plates laser cut to suit a borg warner from xr-xy falcon to suit the 36 radius rods, just means sorting the front of the wish bones out... What part of Oz are you? X38 has some great idea's there, how many mods do you want to do? A friend has done what you are speaking of with his 36 coupe, bw diff on paralell leaves, celica 5spd behind 8ba... he's a member on here, havn't seen him for a while, will try to track him down. Can't think of his tag... Sent via carrier pidgeon & smoke signals with the HAMB App
Hi guys, I'm based in Bendigo. The wheels are 15 x 7 but with the tall Firestone 255 tyres. I have enough room on the inside to move the wheels in an inch and this will then clear the guard. I don't want to keep the banjo so yes looking for a rear end set up with leaf springs and a diff that can give me the right ratio, not worried about which brand we use. My preference is to keep the 3 speed and stay with the old school era but I might have to change. The T5 is probably going to involve clutch linkage changes etc which won't be an issue if I keep the 39 box or even go with a 4 speed from a 50s pickup but won't drive as well. It would be great to catch up with Outback's friend with the 36 and have a chat.
Check your rear end ratio, there were several. Most were 3:78 which gives me 60 mph at about 2600 with a 29" tall tire, there were also 4:11 which would give you quite a bit higher rpm's. I put 3:54 in the rear end on my coupe I'm building now. Tire height X 3.14 = diameter; divide by 12 to convert to feet. Use that number to divide 5280 feet per mile; multiply by rear end ratio = rpm at 60 mph. ( 29 x 3.14 = 91.06; 91.06 divided by 12 = 7.588'; 5280 divided by 7.588 = 695.8; 695.8 x 3.78 =2630 rpm at 60 mph) 29" tire with 3:78 gear is 2630 at 60. 29" tire with 4:11 is 2860 at 60. 29" tire with 3:54 gear is 2463 at 60.
No need to change any clutch linkage if you use the T-5 transmission adapter that uses the stock ford clutch bits. Using the correct adapter allows you to keep as much of the old ford drive train as you want. I used the Offenhauser adapter in front of an S-10 transmission, driving a 46 ford pickup open drive center section with 40 ford axle housings under a 33 ford pickup.
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