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Federal Elise 2005. BOE Rev400. Supercharger. Norway
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Discussion Starter · #1 ·
Hi,
Transmission broke after 14 years of use with 292whp. (3rd gear of my OEM C64 w/LSD gearbox)
If it's relevant, the car is not used on the race track so far, so normal road use only.

I am therefore seeking advice on what to do next:
#1 - One option is to replace the 3rd gear with a used OEM 3rd gear (parts are around $100). It's fairly cheap, but I assume at some point it will break again (it took 14 years... so it might last a while)

The other options are to upgrade the 3rd and 4th gear:
#2 - For example, with the option from JUBU RACING

The third option is to replace the whole gearbox / transmission. If so, there are at least 3 options:
#3 - C64 w/LSD. Original setup.
#4 - C60 w/LSD. From the Celica GT. I know that the gear ratio is the same, except the 6th gear will have a lower RPM on the highway, which is nice. However, I struggle to understand if the C60 is actually somehow enforced / stronger than the C64 or identical?
#5 - E153 w/LSD. From the MR2 Turbo. It seems like this is indeed enforced / stronger than the C64. However, does this also come in 6-speed? I also understood that you need to replace the driveshaft with this option.

*I've taken it for granted that LSD is the natural choice when having 292whp.

I've researched as best as possible, but I'm not sure what is the best option, as there are pros/cons with all options. So hoping to get some advice that might help.

My goal is to find a good solution within the range of $1000-2000.

Thanks for any advice from those of you with experience on this topic!
Much appreciated.
 

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When you say broke, did the gear actually shatter and spray bits all over the inside of the transmission?

That Jubu solution looks good. You can also look at Monkeywrench Racing who sell the SSC and Kaaz gears or Blackwatch Racing where Fred has a more comprehensive upgrade to the gear set.

Given you are street-only, the SSC or Jubu 3rd/4th is probably all you really need to do (in addition to replacing all the synchros while you are in there).

Where are you planning to get the rebuild done?
 

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Federal Elise 2005. BOE Rev400. Supercharger. Norway
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Discussion Starter · #3 ·
When you say broke, did the gear actually shatter and spray bits all over the inside of the transmission?

Where are you planning to get the rebuild done?
Hey man,
Thanks for the reply. So far, I haven't opened the gearbox, so not entirely sure how it looks like in there. But I don't believe it's "too bad". It suddenly started to make "scratchy sounds" as I was driving downhill and "hanging on 3rd gear". So it was not during acceleration at all. I drove the car afterward, without any noise, as long as I drove 1-2mph ish. As soon as I passed 5mph (ish), the scratching noise came back, so I stopped. I took the car on a lift and could confirm the noise came from the gearbox and not the supercharger of the engine itself.

I am not 100% certain it's 3rd gear, but I feel fairly confident.

So far, I haven't started looking for a place to rebuild, as I'm not sure yet if it will be to replace parts or fully replace the gearbox itself. (for now, pending feedback on this thread)
 

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1. That sounds like your clutch and no idea why you think its 3rd gear.
2. if you dont know how to rebuild a trans there is no $1-2000 option and even if you do the first rebuild needs $500 in tools and $500 in bearings and synchros.
 

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Federal Elise 2005. BOE Rev400. Supercharger. Norway
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Discussion Starter · #5 ·
1. That sounds like your clutch and no idea why you think its 3rd gear.
2. if you dont know how to rebuild a trans there is no $1-2000 option and even if you do the first rebuild needs $500 in tools and $500 in bearings and synchros.
1st gear and reverse works fine on low speed. I believe it is 3rd (or 4th) because that’s the gear I was in when it broke, as well as the C64 is known to have a weak 3rd and 4th gear when used with a high HP engine. Thus my assumption of it being a gear, and not the clutch. But I’m all ears for good inputs! 👍🏻

I can buy a used trans for below $2000. That I can fit myself, but rebuilding one is out of my league, so would need assistance from someone more skilled if I choose that path.
 

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BWR 3/4 gears. You'll be fine.
 

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I cant believe I have to ask this, but does.... 3rd gear work?......
 

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If you have are not on track, autocross or something, then the LSD is probably just jewelry. To be clear, that is a perfectly valid reason to have an LSD, but you could just tell people that you have an LSD, if you are never on track or something equivalent, nobody would ever know. Mathematically, that would be 100% cheaper than any other solution.

On the gear stripping, I agree with the advice above (get the uprated 3-4 gears), but I would also point out that an open diff puts less stress on the transmission than an LSD. So maybe instead of stripping a gear you might smoke a tire. It's all about the trade-offs.
 

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Chotto, kfennell, and Lotusninja are all spot on. For street-driven car, LSD is not necessary. If you choose to beef it up, our 3/4 gears are a good way to go. I have pulled my fair share of Broken Jubus out of transmissions albiet hard tracked cars. New clutch and re-surfaced flywheel when you are in there seems the obvious choice.
 
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