One out, one in

I have been meaning to tell you this for a long time but I felt it would offend you. I have driven several SMT Spyders and they are painfully slow. I do like the downshifts but the upshifts  slow this car. I can see it being even slower with the Euro transmission gear ratios.  I think the best modification is a manual swap with the US/JP C56 transmission. 

A quick google search shows the SMT Roadster does 0-60mph in 8.8 seconds. 

http://accelerationtimes.com/models/toyota-mr2-1-8-roadster-smt

  With a manual conversion it would be substantially quicker. Maybe 7 seconds if not faster. That kind of performance difference like adding a turbo on some other cars.  

I don´t disagree but there´s three things Dev:

- I have two titanium hips and the left leg is not up to traffic clutchwork

- It´s not thát bad 

- As automatics go I quite like the smt

I understand and that is unfortunate. I checked the best and worse times for 0-60 and they are all over 8 seconds which is slow even by cars of this type for the last 30 years. 

How about this. If possible as I don’t know what is involved how about changing the final gear ratio in your transmission.  

Posted by: @dev

 

How about this. If possible as I don’t know what is involved how about changing the final gear ratio in your transmission.  

Seem that nó road tester was aware that the smt doés have a launch option... Rev the engine like you would on the manual, then push the gear lever to the right, in gear and the smt wíll engage/drop the clutch, burn rubber, just like a manual.

Gear shifts go way quicker if you slightly lift off when shifting. Again just like manual. 

The smt boxes are the same as the manual boxes. Diffs too as is the clutch.

Posted by: @dev

I understand and that is unfortunate. I checked the best and worse times for 0-60 and they are all over 8 seconds which is slow even by cars of this type for the last 30 years. 

How about this. If possible as I don’t know what is involved how about changing the final gear ratio in your transmission.  

Changing the final gearing requires complete disassembly, as in removing the gears and syncro assemblies from the output shaft, installing them on the new output shaft, changing ring gear and reassembling.  It's pretty much a complete trans overhaul at that point.

If I was going to change the final gearing and keep the car an SMT, I would probably find a manual trans with the gearing I wanted and swap main transmission housings and clutch fork, that way you have the gearing you want and the SMT stuff still bolts up.  The disassembly required would be unbolting the bellhousing, main case and the end case and only pulling off the 5th gear set (and 6th if you have it).  The thing is you would want to stay with whatever your SMT is, i.e. if your SMT is a 6 speed, stick with a 6 speed trans, otherwise there's a whole new level of headaches.

I am very much ok with the box in my car. 

If the clutch would need replacing or waht, I would most likely stay with the OEM flywheel/clutch even.

Ám curious about the codes for the type of diff / reduction but that is a different thread and not related to mý car nor to the mod. itch 😊 

Posted by: @nocoolname

Posted by: @dev

I understand and that is unfortunate. I checked the best and worse times for 0-60 and they are all over 8 seconds which is slow even by cars of this type for the last 30 years. 

How about this. If possible as I don’t know what is involved how about changing the final gear ratio in your transmission.  

Changing the final gearing requires complete disassembly, as in removing the gears and syncro assemblies from the output shaft, installing them on the new output shaft, changing ring gear and reassembling.  It's pretty much a complete trans overhaul at that point.

 

If I was going to change the final gearing and keep the car an SMT, I would probably find a manual trans with the gearing I wanted and swap main transmission housings and clutch fork, that way you have the gearing you want and the SMT stuff still bolts up.  The disassembly required would be unbolting the bellhousing, main case and the end case and only pulling off the 5th gear set (and 6th if you have it).  The thing is you would want to stay with whatever your SMT is, i.e. if your SMT is a 6 speed, stick with a 6 speed trans, otherwise there's a whole new level of headaches.

   Thats interesting stuff.  Its too bad the aftermarket were not able to improve on the system. I remember that LR tried to make a 2ZZ SMT and had it working for a time but it was riddled with problems. If money was no object I would love to get a sequential Quaife but I wonder how loud it would be in the cabin and if it required frequent rebuilds. 

If looking for lightness without ripping the gearbox out, maybe go after the other pullies besides the crank. You could also try the overrunning alternator decoupler pulley like I have done. It definitely adds a feeling of liteness to the car, moreso than just a lighter pulley. The alternator being allowed to freehweel while decelerating makes for much smoother on/off throttle transitions and way smoother shifting. I'd be very curious to know how it would work with the SMT, I'd like to think it would be a good thing for SMT.

@marsrock7

Thank you. Have a lightweight underdrive alternator pulley already.

The crank pulley is a bit controversial. 

Posted by: @petrus

@marsrock7

Thank you. Have a lightweight underdrive alternator pulley already.

The crank pulley is a bit controversial. 

Decoupling is vastly superior in my eyes. If you still want underdrive too, maybe a decoupler larger than 60mm could be found. (I think the OEM 1zz pulley was 60mm) Can't say I have looked for a larger one thou. 

Edit: 1ZZ pullies have been found to be either 52.5mm or 55mm, possibly depending on ore or post-facelift.

Posted by: @marsrock7

Posted by: @petrus

@marsrock7

Thank you. Have a lightweight underdrive alternator pulley already.

The crank pulley is a bit controversial. 

Decoupling is vastly superior in my eyes. If you still want underdrive too, maybe a decoupler larger than 60mm could be found. (I think the OEM 1zz pulley was 60mm) Can't say I have looked for a larger one thou. 

I think you have me almost convinced so I looked into it. My only worry is if I have enough room to fit my air gun to remove the pulley on my car. I really don’t want to remove my alternator. I did it twice already and it sucks.  

Posted by: @petrus

- I have two titanium hips and the left leg is not up to traffic clutchwork

 

 

That's a shame! I've had my titanium hips since 2015(I'm 70 now). I've driven many thousands of miles in the 5 years I've owned my current C60 equipped Spyder, with zero problems.

Enjoy your Spyder 👍 👍 

Can't wait for my titanium hip lol

Posted by: @marsrock7

Posted by: @petrus

@marsrock7

Thank you. Have a lightweight underdrive alternator pulley already.

The crank pulley is a bit controversial. 

Decoupling is vastly superior in my eyes. If you still want underdrive too, maybe a decoupler larger than 60mm could be found. (I think the OEM 1zz pulley was 60mm) Can't say I have looked for a larger one thou. 

Got this backwards.... Read back into the OAD pulley thread here and the pullies I have from 1ZZ are 52.5mm. I think another reported their 03+ 1ZZ had a 55mm. So, depending on the size of your stock pulley, you could still underdrive with a 55mm or greater, along with decoupling. 👍

On another note, if anyone is looking for a really cheap way to underdrive their alternator, the 03-07 Accord, CR-V, TSX, most anything with a first generation K24 uses a 7rib 60mm pulley that will fit right on to our alternators. You'll just have one extra rib of space after you put the belt on. I have way too many of these in my garage right now. 😛