The Lotus Cars Community banner

1 - 20 of 21 Posts

·
Registered
Joined
·
8 Posts
Discussion Starter #1
It was brought to my attention that many of the Elise owners are having some transmission issues.

The two most common seem to be:

Syncro failure in hard driven cars

Gear failure in forced induction cars

I'm considering producing a uprated gear set for the 6mt.

What I'm curious about is what exactly you guys would like to see from such a set other than the things listed above.

thanks for your time,

Dylan @ DS1
 

·
Registered
Joined
·
304 Posts
The gear box just feels notchy for lack of a better term. My Honda Civic is like butter compared to the Lotus. If the gearbox hasn't warmed up yet, forget about getting into 3rd on a cool day. I just drive mine back and forth to work with the occasional spirited drive on some back roads, but the gearbox is near the top of the list for complaints for me. Fix that my friend and you'll be my hero. :shift:
 

·
Puff Daddy
Joined
·
3,872 Posts
6th gear is too short.

My biggest complaint isn't how it feels... it's the crappy ratios that Toyota seemed to have picked.

You can't stay in lift between first and second, 3rd gear is too tall, and 6th isn't any sort of overdrive gear. :wallbang:
 

·
Registered
Joined
·
438 Posts
6th is shorter in the elise trans. as compared to the normal celica GTS 6 speed it is longer and you can just swap the gears if you wanted to.


If you are going to make stronger gears you will sell a lot of them to other platforms that use the same transmission besides the lotus like all the celica, mr2, and others like vibe, matrix, corolla..etc..


3rd and 4th are the main issues with these transmissions, strengthen them up and sell at a decent price and you will have a market. I have tried a few times but no real interest by production side of things to get them done at a reasonable cost, but if you make and sell them yourself at a reasonable price you'll sell them trust me.

most people that make more power and break the gears also want longer gears, not just stronger.
 

·
Registered
Joined
·
787 Posts
Gear ratios need to be closer. RPM's drop off too much on upshifts and drop out of powerband. Probably my only ongoing complaint with the drivetrain.

I have had no issues with the integrity of the transmission and I'm putting 325 HP through it.
 

·
00 MRS - 2ZZ NA
Joined
·
1,228 Posts
6th is shorter in the elise trans. as compared to the normal celica GTS 6 speed it is longer and you can just swap the gears if you wanted to.


If you are going to make stronger gears you will sell a lot of them to other platforms that use the same transmission besides the lotus like all the celica, mr2, and others like vibe, matrix, corolla..etc..


3rd and 4th are the main issues with these transmissions, strengthen them up and sell at a decent price and you will have a market. I have tried a few times but no real interest by production side of things to get them done at a reasonable cost, but if you make and sell them yourself at a reasonable price you'll sell them trust me.

most people that make more power and break the gears also want longer gears, not just stronger.
x2. The tranny is one of the reasons I'm not going turbo.

Plus even with the Kaaz/C-one gearset, the transmission might still give out, even if it's made a little bit stronger with the gearset in them. MWR had them on their drag GTS that broke into the 10's, and they still had to switch out to the more sturdy automatic GTS transmission. Be sure to make an even better product.
 

·
Registered
Joined
·
1,372 Posts
I'm curious how you intend to make the gears stronger, since the center to center distance is already predetermined by the existing case. This rules out larger gears. Slightly more width might be possible. Changing the angle to more of a spur gear will increase the load rating (and noise) significantly. Have you identified the alloy Toyota used? I doubt it's that bad and going with something more ductile to reduce breakage will be a trade of as far as rate of wear. I don't really see gear breakage as an issue with the Lotus anyway, it's a light car and most people here aren't overkilling the trans with power. You may want to do a survey and see how many owners have broken a gear.

As far as improvements, keeping on the big cam without thrashing to the rev limiter is desirable. The 1/2 shift is the worst as far as rpm drop. A taller 1st gear is one way to fix it. 1st is pretty much unusable for the track. Make it closer to 2nd and it might get used occasionally coming out of a tight turn. @nd gear synchro will have less work when upshifting, hence more lifespan.

The biggest problem with the gearbox is the short lifespan of the 2nd gear synchronizer. Of course we have to downshift a lot into 2nd to keep the rpms up. It's more work for the synchro than upshifting. You can do the math. Also, your dealing with the braking action of all the fluid you're churning. When you upshift, it works in your favor. When downshifting, it works against you. One member made a dog style gear for 2nd out of frustration. No more synchro to wear. This isn't for everyone's taste however.
 

·
Registered
Joined
·
787 Posts

·
Registered
Joined
·
1,316 Posts
Straight cut gears and dog rings. Perfect for the track and the used parts will be cheap when the poseurs get tired of the gear whine in their street cars.
 

·
Registered
Joined
·
438 Posts
let me know what kind of parts you will need, i have a few different transmissions around i can give you if you get serious and want to go ahead and make some gears.
 

·
Registered
Joined
·
1,734 Posts
With my Katana Elise, on my local track, I'd need:

-a shorter (more usable) 5th gear
-a longer 6th (because I'll never use it on any track anyway...) :p

I feel that 3rd gear is very good with the Katana. :shrug:
 

·
Registered
Joined
·
8 Posts
Discussion Starter #17
Ok these are the things I have for the list so far:

3rd gear is too tall

2nd-4th syncros

6th too short

Ratios too far apart.


As for strengthening them there are many options:

Material
Hardening process
Finishing process
Tooth profile/ depth/ width
Ratio choice

As for price I am shooting to stay under the cost of a new trans for the 1-6 kit fully installed. :nanner:

Dustin- I will be in contact with you this coming week. :)

-Dylan @ DS1
 

·
Registered
Joined
·
438 Posts
PS, Quaife does make a gear set already sooo, you should compare your idea's to theirs so they arent the same thing and you'll be offering a better price and also another option.

Complete 6-speed dog engagement gear kit, semi helical, close ratios. Includes Quaife strengthened end cover and final drive ratio.

Ratios:-

1st 2.583
2nd 1.929
3rd 1.563
4th 1.333
5th 1.158
6th 1.048

Final Drive:-

4.800
 
1 - 20 of 21 Posts
Top