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Posted: 06-05-2017 06:13 pm |
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Esprit2
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Just for the record, Lotus used three different 5-speed transmissions with the 907 & 912 engines. Any of which, when taken with it's dedicated Lotus bell housing, would be a direct bolt-on fit with the JH 907 engine. If you also use the Lotus flywheel and clutch, there should be no fabrication required just to mate the transmission to the engine. All the Lotus transmission's bell housings are set up for a cable actuated clutch with the release lever on the right side. All the Elite-Eclat-Excel gear levers poke through the consol at about the same point. Since the Excel's W58 gear lever must be re-located to fit the JH, it's reasonable to presume the other two gearboxes would also require gear lever mods. The first Elite-Eclat 5-spd was a Lotus-built unit. It used the Austin Maxi gearset plus a Ford shifter mechanism, all stirred together into a Lotus-specific housing. There was a short tailshaft version for the Elan & Elan +2, and a long tailshaft version for the Elite-Eclat. Owner/ users usually refer to it as the Lotus-Maxi 5-spd. The Maxi gears were okay with the 1558cc Twin Cam in the lightweight Elan, but it was beyond it's comfort zone behind the more powerful 2.0 907 in the heavier 4-seater Elite-Eclat, and it's clearly in over its head behind a hotrod 2.2 liter 907/ 912. The Lotus-Maxi's intermediate ratios were probably the best ever offered for the 907, and the shift action was a delight. The O/D 5th was 0.800:1. That's not as tall as the Toyota W58, but still a comfortable cruiser. However, if any of these three gearboxes was going to be problematic with the 907's power, then I'd bet on it being the Lotus-Maxi. I wouldn't recommend going out of your way to pursue one, but if one followed you home it would be a relatively easy installation. Emphasis on 'relatively'. The JH Getrag 235 has a dog-leg 1st gear (to the left & back) and a 1:1 5th gear ratio... same as the J-H 4-speed. It's NOT overdrive, and the JH5/ JGT get their improved cruising capability via a taller, 3.45:1 final drive ratio... NOT an overdrive transmission.. The JH-stock Getrag 235 would be comfortable handling the power of a street-hot 2.2 9XX. The 1981-82 Elite-Eclat S2.2 got the 912LC engine and a Getrag 265 5-spd. "265"... it's NOT the same Getrag 235 used in the JH5 and GT, and it won't mate with the JH5/ JGT bell housing. But the Elite-Eclat S2.2 bell housing will bolt right up to the JH 907. The Lotus Getrag 265 has a 'normal' 4-spd shift pattern, plus 5th to the right and forward... one more natural step. The 265 was also used in some BMW applications, it's considerably more robust than the Lotus-Maxi, and it is very durable behind any of the 907/ 912 engines. Some critics say it's more coarse in operation, and not as nice shifting as either the Lotus-Maxi or Toyota W58 5-speeds. But if you didn't have them for comparison, you probably wouldn't notice (ie, it was acceptable in BMW cars). The Getrag 265 is a true overdrive gearbox, with a 0.813:1 O/D 5th gear ratio, making it an easier 'overdrive' conversion for a 4-spd J-H. However, it's the least 'over-driven' of the three Lotus 5-speeds (verses Lotus-Maxi & W58), but it's not much different compared to the Lotus-Maxi. The Excel and Excel SE both got the Toyota Supra's W58 5-spd transmission that gets so much attention from JH owners. And deservedly so. Lotus used the later, beefed-up version with the steel sandwich plate. Overall, It's probably the best transmission ever mated to the 907/ 912, it can handle the most power, and it has the best conversion parts support and knowledge base. The last two points make the W58 the best contender for a JH swap... IMHO If you wish to bring in a 4th option, the Toyota W57, then the 265 is considerably more 'over-driven' than the W57 (Conversion Components refers to the W57 as the "Close Ratio" Toyota 5-spd). Lotus never used the Toyota W57, but since it was mentioned above, I'll add the following info. The W57 is basically a W58 without the strength enhancements and with the lower 0.861:1 O/D 5th for smaller, less torquey engines that can't pull a tall O/D. That lower 5th might make it a better option for replacing the stock JH Getrag 5-spd with the 3.45:1 rear axle ratio. Regards, Tim Engel Last edited on 03-30-2020 06:14 pm by Esprit2 |
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