### Quantum Mechanics/John Esposito's 5-speed Offering for Elans

Posted:

**Wed Aug 19, 2009 12:37 am**Hi all.

There has been a lot of interest over the years concerning a better gearbox for the Elan. John Esposito of Quantum Mechanics in Monroe, CT USA now offers a 5-speed gearbox with a choice of ratios. The box assembly is based upon the Ford t9 and utilizes John Voight's conversion that adapts the t9 for use on Elans and probably Cortinas and Lotus Sevens. Most importantly, alternate gear ratios are now made available courtesy of BGH Gear Tech. John's announcement has been posted in another thread but I repeat it here.

download/file.php?id=7076

download/file.php?id=7075

What John has done is pull together disparate parties to offer a really good solution to living with an Elan in today's world. Interstrate traffic here routinely flows at 80+ mph. Relaxed cruising at these high speeds is really desireable.

I don't know if this gearbox will ever be legal in the racing world. The argument I would make before a santioning body is that it does not offer performance advantages except maybe in an endurance races. The fact is that this gearbox offers performance gear ratios between the semi close ratio and close ratio Lotus offerings. It offers a potential higher top end, but probably weights more, even with the optional alloy t9 casing. It is unlikely that top gear would be used in normal circuit racing unless rear end ratios were adjusted numerically higher. The fact that all housings would be aluminum, means that oil control should be very good, due to similar coefficients of themal expansion. In other words, the gasket interfaces will change with temperature at about the same rate.

The real beauty of this gear box is it enable's relaxed high speed cruising.

For those of you contemplating a 5-speed gear box of this type, I offer the attached Excel file plotting some of the more desireable ratios that are available.

Data labels for the individual ratios for each gear set are alligned vertically. The height of the label corresponds with the plotted point at the 1-5 positions. For the Lotus 4-speed ratios, only 4-points are shown.

The legend connects the plots to specific BGH offerings and compares them to the Lotus semi close ratio and close ratio offerings (in heavy dotted lines). This provides a basis for gear ratio comparison. Not all BGH ratios are shown, only those I've selected for comparison. In my opinion these are the ratios of interest.

Want the closest thing to a close ratio gear set but a 0.82 OD, slelect the E7A gear set. Want the closest thing to a Lotus semii close ratio gear set, select the E2A gear set.

For me, I selected the E7A gear set. This gear set offers gear ratios between the close ratio and semi close ratio gear sets, but closer to the close ratio gear set. First gear is a bit lower, but the following ratios are very close to the close ratio ratios. I think this fits my S2 very well in that it provides a slightly lower first gear for starting on hills, but close to the close ratio gear set, making it better for my driving style. First gear is a little more friendly than the close ratio for starting on a hill, but also makes first gear more user friendly for general use. Somone with a +2 or heavier baby Elan, might want to consider the E7E offering that substitutes the E7A's 2.66 first gear for the E7E's 2.75 first gear. It was a tough call for me with my S2 and 3.55 rear end. For someone who just wants an OD for cruising, select the E2A ratio.

The E7A, E7E and E2A ratios provide a 0.82 OD transmission ratio in fifth gear. This results in an 18% reduction in top gear rpm for a given speed.

Bill

There has been a lot of interest over the years concerning a better gearbox for the Elan. John Esposito of Quantum Mechanics in Monroe, CT USA now offers a 5-speed gearbox with a choice of ratios. The box assembly is based upon the Ford t9 and utilizes John Voight's conversion that adapts the t9 for use on Elans and probably Cortinas and Lotus Sevens. Most importantly, alternate gear ratios are now made available courtesy of BGH Gear Tech. John's announcement has been posted in another thread but I repeat it here.

download/file.php?id=7076

download/file.php?id=7075

What John has done is pull together disparate parties to offer a really good solution to living with an Elan in today's world. Interstrate traffic here routinely flows at 80+ mph. Relaxed cruising at these high speeds is really desireable.

I don't know if this gearbox will ever be legal in the racing world. The argument I would make before a santioning body is that it does not offer performance advantages except maybe in an endurance races. The fact is that this gearbox offers performance gear ratios between the semi close ratio and close ratio Lotus offerings. It offers a potential higher top end, but probably weights more, even with the optional alloy t9 casing. It is unlikely that top gear would be used in normal circuit racing unless rear end ratios were adjusted numerically higher. The fact that all housings would be aluminum, means that oil control should be very good, due to similar coefficients of themal expansion. In other words, the gasket interfaces will change with temperature at about the same rate.

The real beauty of this gear box is it enable's relaxed high speed cruising.

For those of you contemplating a 5-speed gear box of this type, I offer the attached Excel file plotting some of the more desireable ratios that are available.

Data labels for the individual ratios for each gear set are alligned vertically. The height of the label corresponds with the plotted point at the 1-5 positions. For the Lotus 4-speed ratios, only 4-points are shown.

The legend connects the plots to specific BGH offerings and compares them to the Lotus semi close ratio and close ratio offerings (in heavy dotted lines). This provides a basis for gear ratio comparison. Not all BGH ratios are shown, only those I've selected for comparison. In my opinion these are the ratios of interest.

Want the closest thing to a close ratio gear set but a 0.82 OD, slelect the E7A gear set. Want the closest thing to a Lotus semii close ratio gear set, select the E2A gear set.

For me, I selected the E7A gear set. This gear set offers gear ratios between the close ratio and semi close ratio gear sets, but closer to the close ratio gear set. First gear is a bit lower, but the following ratios are very close to the close ratio ratios. I think this fits my S2 very well in that it provides a slightly lower first gear for starting on hills, but close to the close ratio gear set, making it better for my driving style. First gear is a little more friendly than the close ratio for starting on a hill, but also makes first gear more user friendly for general use. Somone with a +2 or heavier baby Elan, might want to consider the E7E offering that substitutes the E7A's 2.66 first gear for the E7E's 2.75 first gear. It was a tough call for me with my S2 and 3.55 rear end. For someone who just wants an OD for cruising, select the E2A ratio.

The E7A, E7E and E2A ratios provide a 0.82 OD transmission ratio in fifth gear. This results in an 18% reduction in top gear rpm for a given speed.

Bill