Transmission rebuild
#1
This is going to be my transmission rebuild thread once I source all the parts and find the time/space to do this. As my trans rebuild gets underway, I'm debating a few things.

1) TRD Clutch type LSD

2) Lightweight flywheel.

I probably will get the LSD but the flywheel I'm not so sure about. Is it worth it for track abuse in a momentum car? What are the advantages and disadvantages. I had one on the Prelude but never drove it without a stock flywheel so I've got no idea what it's suppose to feel like.

Any of you track guys have a LWFW? What are the pros and cons?
Two feet.
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#2
I think the lightened flywheel allows your engine to rev high faster and lose rpms faster. In some cars though, I don't know if yours is the case, if you go TOO light, you'll actually throw some CELs. Just be aware of that, do some research on MR2 forums and find out what people are having success with
Posting in the banalist of threads since 2004

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#3
how much does the stock flywheel weigh? I've seen lightweight flywheels really wake up some engines (like when BMW puts a 27lb one on a 4cyl engine), but some aren't that much of a savings and don't seem a high priority.
The only thing that stops a bad guy with a van is a good guy with a van
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#4
I have a lightweight aliuminum flywheel on the XR and I really like it. I also have a centerforce stage 3 clutch, and the combo of the two is really nice. The flywheel allows the engine to rev quickly and fall quickly, while the centerforce si very drivable yet strong enough for the car.

In racing, from what I understand (and racers correct if I am wrong) you don't really want the engine to do much other than accellerate. Slowing down is the responsibility of the brakes. As such, the quicker the engine can rev and the faster it can fall off, the better. Heel/Toe is easier because the engine reacts more quickly too. It's less weight on the car a whole and less mass for the engine to rev.

I'd say go for it!
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#5
9 lb flywheel in my car, well worth it Smile

Mine is a Toda FW/Clutch Kit, I believe they make one for your engine as well, its a very nice piece.
(09-25-2019, 03:18 PM)V1GiLaNtE Wrote: I think you need to see a mental health professional.
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#6
i've got a lightweight flywheel... didn't really notice a difference. that could be because the difference between light speed and ludicrous speed isn't all that much.
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#7
wouldnt getting a used transmission be a lot cheaper and faster than a rebuild?
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#8
back when i had my integra, i had bought a used type R flywheel when i had a new clutch as well. i think the type R flywheel was like 7 lbs lighter than the stock LS flywheel. it felt much more rev happy but i dont think i ever tracked the car with the old flywheel so i cant really compare it for track conditions
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#9
Evan Wrote:wouldnt getting a used transmission be a lot cheaper and faster than a rebuild?

when has anyone in MM done anything the "cheap" and "easy" way? maybe he wants the experience! You, RJ, Chad, and Pete all built your cars... Smile thats not the cheapest way to do things... or the fastest!
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#10
According to some members of the board, our stock FW is 23 lbs. That seems insanely high to me but I'll verify tonight. I have a spare trans/engine that I'm going to swap with the broken one.

I'm going to rebuild it and have it ready for next season. 91-92 MR2's trans with over 100k tend to all have failed or failing synchros. Buying a revised/improved 93+ trans with dual cone synchros is actually more expensive than rebuilding one.


Then again, I might end up swapping in a turbo engine. We'll see what time/space will allow.
Two feet.
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#11
Are you going to rebuild it yourself? Is there anything wrong with it now?
(09-25-2019, 03:18 PM)V1GiLaNtE Wrote: I think you need to see a mental health professional.
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#12
.RJ Wrote:Are you going to rebuild it yourself? Is there anything wrong with it now?

Yeah. I'm going to do it myself. The trans in the car now is bad. 2nd, 3rd, 4th synchros are pretty shot. 4th gear popouts and both 3rd and 4th won't go in above 5k without hamfisting it in. I also haven't been able to get into reverse without first putting it in 1st gear for sometime.

Hmm . . .let's see what else is wrong with it . .. nope, I think I covered it all.

I would complete the rebuild in August but the prohibitive cost of the LSD is slowing down the parts build up.
Two feet.
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#13
yeah, 23lbs is pretty rough, if you could get that cut in half, it'd be a noticeable difference. Downsides are noise and vibration, maybe trickier clutch engagement at low RPMs, some cars are even prone to stalling if the idle isn't increased a bit.
The only thing that stops a bad guy with a van is a good guy with a van
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#14
BLINGMW Wrote:some cars are even prone to stalling if the idle isn't increased a bit.

my talon would stall, but I think the big part of that was from the lope caused by the bigger cams
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