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| | | | Joined: Oct 2013 Posts: 2 New Guy | | New Guy Joined: Oct 2013 Posts: 2 | I can only get about 40mph and the engine sounds like it wants to come out from under the hood need to know what I can do and keep the 10 lug rims | | | | | Joined: Jan 2013 Posts: 1,384 Shop Shark | | Shop Shark Joined: Jan 2013 Posts: 1,384 | Some more details Please
20 x 7.50? 4 speed? 2 speed rear?
Does sound like 2 speed axle in low range.
Attach a hand held tachometer and see what the rpm really is. | | | | | Joined: Oct 2013 Posts: 2 New Guy | | New Guy Joined: Oct 2013 Posts: 2 | OK it has single speed rear axle and 7.5 20 tires. It has a 58 235 with 4 speed trans | | | | | Joined: Jan 2013 Posts: 1,384 Shop Shark | | Shop Shark Joined: Jan 2013 Posts: 1,384 | There were 2 rear end ratios available, about 6.2 and 5.4.
With 7.50 bias ply at 60mph you would be doing about 3550 rpm or 3050 rpm respectively. | | | | | Joined: Jan 2011 Posts: 32 New Guy | | New Guy Joined: Jan 2011 Posts: 32 | Empty with my 1949 4400, I can only get 35-40 mph. It too has single speed rear end, and the 7.50 x 20" tires. Not sure on the rear end ratio, but I do know the 235 came out of a late 50's sedan. Just how do you get 60mph out of the old stock truck? 60mph in this old girl would be fun, but might be a handful.
1949 1.5 Ton 4400, 1969 c10, 1989 c1500, 1990 K2500, 2010 C1500 Crew
| | | | | Joined: Dec 2002 Posts: 2,549 'Bolter | | 'Bolter Joined: Dec 2002 Posts: 2,549 | I had 8.25 20's, on the '49 4400 I had, & could get 50 mph out of it. Also had a single speed rear axle. | | | | | Joined: Dec 2003 Posts: 1,144 'Bolter | | 'Bolter Joined: Dec 2003 Posts: 1,144 | You could change to 8.25 or 9.00 tires on rear. Also keep in mind these trucks do not have the sound proofing a more modern vehicles have so more noise makes it to your ears. Truck speed limits at the time in many states often were only 45, I'm quite sure many drivers exceeded that. | | | | | Joined: Nov 2010 Posts: 1,159 Shop Shark | | Shop Shark Joined: Nov 2010 Posts: 1,159 | I have 9:00X20:00's,on my 6500.(2-speed rear). Top speed is 55.(Hi-side). I wouldn't push the engine past its "Happy Zone". I still have a 1/4" left in the pedal travel,so I could go faster,but I don't want to shell a GOOD 261,that's survived 58 years. You may use the same rims,since the diameter of the tires stay the same,just a taller sidewall/profile. This may get you up to 50 M.P.H.,depending on your rear-end ratio. | | |
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