Will this work very well? My 1951 3100 has a 1965 283c.i. engine(stock as far as I know) I am hooking up a 700r4 tranny to it soon. The rearend is from a 1970 1/2 ton truck with 3.07:1 gears. Tire height to be 26/27 inches. This will be a daily driver with minimal highway driving so it should rarely get to the overdrive but will need to on occasion. Not building a drag truck or pro street just want to drive it more that I do now. Will this setup work or should I regear to more like 3.55:1 which I have a friend who says that is a great setup? I'd rather do gears later if this works and spend that money on the Budnik rims now.
left lane soon sounds like you will be in the left lane soon let us know how the rear end swap turns out. Robert
If I'm not mistaken, the 700r4 has an OD ratio of .70. You need to run the numbers and see if you stay towards the top of the torque curve at cruise rpm for your specific 283. I like the bottom calculator: http://csgnetwork.com/multirpmcalc.html I'm afraid that your current 3.07 R&P might be just a bit too tall to let you gain any advantage from the 700r. Plug in the 3.55 and also a 3.73 and see if they might be more applicable. Dave
I think if your running a 3.07 rear gear forget the 700-r4,its not needed if your not going to be running a lot of miles on the highway. The 3;55 with a 700r-4 is a great choice .I have run that with 200hp up to 500 hp and it works out well. I guess i dont listen to myself as i have been running a 2;73 with a 5 speed stick behind a 235.It works well but i dont use 4the and 5th gear around town.But it does do a bunch of highway driving .Great mileage and will run well in the triple digits.(with no wife or law enforcement around)
phat can you run 65 staying in 3rd gear??? iam about to do rear end and tranny swap and i only have a 3speed transmission. thanks Robert
Thanks for all of the info. I figure the 3.55's are in my future. I already have the 700r4 along with a 4L60e that I bought on some bad advice. This is not a truck I would take over 70mph tops, mostly just around town. I am still in a delimma because the rear end is too wide, 58 inches for what I want to do with wheels/tires plus it has six lug axles. Could have a Moser rear end made to what I want with gears and brakes but Im finding it hard to part with that cash. Looking everyday for a substitute rear diff that closer to what I need. Keep those suggestions coming though, I need all the help I can get.....Ken
Hey Robert I can run 65 in 4th and that is 1 to 1 like your 3rd gear. my 5th gear is overdrive. I would say 3.08 if your on the highway a lot but no load.I think i would run a 3.55 with any kind of a load. It would be much easier on the clutch. The 2:73 i put in the truck was a free 4x4 six lug rear from a 80s full size blazer.It will get a 3.55 later as it no longer does long trips.
3:90swould work well with the 700r-4. Dont forget to wire it so you can lock up all gears. It gives you the feeling of having a six speed. How come you need 58 inches? These trucks will take a 61 inch rear. I use the rearends out of 80s 4x4 trucks .They have 6 lug but you can just swap the axles out for five lug 2 wheel drive.Axles can be redrilled at a fraction of what new are
58 inche is too long/wide for the appearance I am trying to get with the wheels/tires. There would be hardly any offset in the wheel at 58 inches. I want to put Budnik Fontana Dishes on it and going as wide as I can with the tire less narrowing the frame. I will also mini tub the bed to gain 2 inches of space that is between the bedside and the frame. This is not being restored to stock but an attempt for a street rod truck. My rear diff problem is also complicated by the coil over ladder suspension that I have to be installed. Brackets weld up to the axle and I dont want to have to take it off after it is on. Next, after this mess is to get the front lower via IFS hopefully.
