914 transaxle higher fifth gear ratio

[theKbStockpiler]

I'm interested if (A) a Beetle with a type IV engine has the torque and B if there is a common method to get rpms down for a cruising speed of 65-70 mph with stock sized tires?


Thanks in advance!

[Piledriver]

A properly built 1700 T4 has plenty of torque, how much do you want?

A 914 transmission w stock dia tires on a beetle will tick over at ~2800 RPM at 70 MPH.
Much lower RPM may be an issue at that sustained load with a T1 fan based cooling system.

I have managed to finally headshot CHT at cruise by running ~19:1 AFR over most of my fuel map, with appropriate timing.

[theKbStockpiler]

A stock 4cylinder 914 transaxle r/p is 4.43 and a beetle 72ish and up is 3.8 to one. A stock 914 first gear is about 3:1 where as a stock beetle first gear is about 4:1. I assume this is to build a stronger r/p from the same materials and using a higher r/p with the stock 914 first gear would be too drastic of a change. I'm thinking that flipping the H gear in the 5th position will be too high for anything under 75mph. It is a jump from .7 to one to .61 to one. Not slowing down in traffic to go into 4th before most other cars would be perfect while keeping the rpms down and still pulling a slight to moderate hill. Is there anything used in a stock 901 that is inbetween a .61 and a .7 ?

[Piledriver]

http://www.914world.com/specs/regearing_901.php lists most all available ratios AFAIK.

The chart uses 205-50 tires, which are quite a bit shorter than 165sr80s.

There is a spreadsheet available at the bottom of that page for registered members.

[theKbStockpiler]

Is it possible to flip an I gear for a fifth gear set? That would give an extra 5mph in top gear. Is second gear with a stock 901 the only gear with limitations and can they all be flipped?