Just looking for some advice. I have a stock 8BA flathead with an overdrive trans and overdrive rear in my 49 sedan. My overdrive doesnt work and somewhere down the line I plan to pull the flathead and replace it with a 302/ spd man. I found a 3.07 Ranger truck rear. Just wondering what the flathead is like geared to the 3.07 rear?? I think the stock overdrive rear is 4.13 ? or something close to that. IM no tlooking for tire smoking just point A to B driving.
Let me see if I got the right numbers but I believe the rear axle gearing in the shoeboxes is as follows: 3 speed no O/D ~ 3:23 automatic ~ 3:54 3 speed with O/D ~ 4:11 The 3:07 obviously will not shoot you off the line, but sounds like you don't want that anyway. It will be nicer on the freeway though. My 2 cents, Fred
Thanks fred, I just want a highway cruiser so I can drive it. I have run it for 100 miles to some shows and shes working too hard without the overdrive at 55mph or 60mph I didnt know how the trans was geared for a swap like that.
I have a 3.79 rear and 20% overdrive box, so that brings the rear down to around 3. no issues on the highway, but I'm running 7.50x16 tyres which are 31" tall to sits on about 2100-2300rpm at 65-70. for around town I just use 4th which is 1:1 and can tool around at 35mph no problem.
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