Axle ratios - first gear almost useless...

[mopetta]

last weekend, I enjoyed a prewar race car meeting at black forest germany. It was amazing to see how good the car (terry tuned engine) works in small hills - I was able to compete with much stronger cars like a BNC 527...

Although the car is a pleasure to dive, I'm a bit unhappy with the 1st gear. Usually I start in 2nd, even on not too steep hills. When using 1st to start, the wheels sometimes spin and top speed is below 10miles. 

• Back axle ratio 5.25 (42/8 teeth)
  
• Gearbox is a 4-speed twin-synchromesh (constant 21-30 / 3rd 1.49 / 2nd 2.36 / 1st 3.89) 
  
• 15inch wheels
  

Looking the the Bill Williams book - a change to 4.9 at back axle combined with 19inch wheels might be a good idea.
Any suggestions what could be a better ratio for my car ?

thanks
Oliver