Hi guys, ive just bought myself a stock 30a coupe and need some advice, Im from the UK so have a couple of months wait until it lands here, Whilst im waiting I thought I may as well sort the suspension. Right the back end I plan on either a t spring or ill just reverse the stock spring, I was wondering how low I can go without splitting the bones, I also need some juice brakes, will these fit the stock spindles and rear axle? Or would it be easier to get 40s spindles? ?
You can use the A spindles with 39 40 backing plates but you need to fabricate a flat spacer with the proper holes in them. I have a set of them around here somewhere. It's easier to 39 40 backing plates. I would recommend using F-1 backing plates with 37 to 48 spindles on the front. They bolt on and you get the bendix self adjusting feature. Just buy the king pins to match your spindles. You can still use the 39 40 rears.
I went with a stock '27 T rear spring (they are flatter than the stock A spring) and reversed the eyes too - and took out a leaf or 2. This does spread the eyes apart so the spring perches on the '40 axle I used needed to be set up accordingly so things didn't bind up or hit! I had to put a leaf back in the spring pack once things settled down after 100 miles or so. I also kicked up the rear crossmember (A frame) to further lower the rear per the BT book. The stock '40 radius arms were refitted to the shortened '40 torque tube and clear the underside of the A frame just fine. Deuce rails would be closer fit though so maybe something different would need to be done. I run '40 drum brakes all round and it stops fine. I used the '40 spindles on the dropped A axle with a needle roller kingpin kit - awesome! Heat and bent the steering arms down to clear the tie rod from under the front split bones. All worked out well - very happy with the result. Check out my build thread for more info.
I know someone here in the UK who has a juice brake set up on his model A and is looking to change back to Rod brakes. I can give you his contact details if you PM me.. Don.
The conversion is easy and been done many times so there is a good history on it. Check out http://www.jalopyjournal.com/forum/showthread.php?t=124112 as well as the archives here and on fordbarn.com. The HAMB site I referenced expresses great concern about slotting the front backing plates and insists that plugging the holes and redrilling them is the correct approach but there have been a lot of conversions with the slots. The guy in the states that does most of the Model A conversions is Dennis Cling at clingsaftermarket.com. He might be a good source for any small parts you need (shipping would dictate you buy the heavy ones locally). He used to have a booklet on the conversion and might still have it but I don't see it on his web site. It might be good to check out the reproduction Lincoln brakes available from http://www.mtcarproducts.com/Brakes.html. They have an interesting approach to eliminating the drum/backing plate interference that might work with the '39-'48 Ford brakes that you should check out. Just for your info, I prefer to use the Model A spindles with a set of adapter rings that cost about $25. If you are looking for ways to mount your master cylinder you might want to check out the bracket at http://www.modelastore.com/Specials, Whats New.htm. With shipping it might be better to build locally but this may give you an idea for design (scroll down the pictures on the left side of the page). Charlie Stephens