PTUNING Close-Ratio 5-speed with Final Drive Dog Engagement Gearset (coming soon)
02-16-2011, 03:44 PM
#22
As most of you guys already know, the factory tC transmission is not designed to handle 400+whp for any period of time, let alone the 550+whp we're putting down with our Time Attack tC. Swapping out transmission gearsets at each and every event made racing a not-so-fun sport for us.
We pretty much decided after the last event of the past season that our TA tC racing days would be put on hold indefinitely until we could find an affordable transmission solution. After all, we weren't about to take the power back down to 350whp just to make the transmission survive a weekend of racing.
Bottom line, if you haven't already sheared the teeth off of fourth gear or broken any other component in the transmission, most likely you're not making enough power. If you have a 400+whp tC that's seen any type of real racing action, chances are you've probably broken a transmission or two before. For the record, we've taken out fourth gear twice just on the dyno alone.
I wanted to give you guys a few technical specs on our gearset. The gears we'll be offering are forged, cryo-tempered, and shot-peened for the utmost strength and durability. After going back on forth on many gear ratios, final drive ratios, tooth profiles, straight vs. helical, and dogbox vs. syncromesh, we've finally settled on this gearset.
We knew the syncromesh engagement hub would be the weaklink at higher HP levels and not even the actual gears themselves so we decided to go with dog engagement gears. When it came to the helical vs. straight cut though, we opted to go with the helical to keep the noise levels down for street use.
This set-up provides us with a streetable, motorsports level gearbox. The dog engagement gearbox will allows you to drive the car like you stole it without being limited to how quickly the syncros want to operate.
We've selected ratios that allow for similar RPM drops between each gearshift (close-ratio) to keep the engine in the powerband for maximum performance. Also, as we all know, the factory first gear is totally useless with big power so we've selected a taller first gear to make it a usable gear.
Below are two examples of the operating range of the gears with a typical 7000rpm redline and our TA tC's 8000rpm redline.
RPM: 7000
Final Drive: 3.538
1st: 2.8 52mph
2nd: 2.083 70mph
3rd: 1.533 95mph
4th: 1.176 123mph
5th: 0.9 161mph
RPM: 8000
Final Drive: 3.538
1st: 2.8 59mph
2nd: 2.083 80mph
3rd: 1.533 108mph
4th: 1.176 141mph
5th: 0.9 184mph
To answer the question on the dedicated drag racing 4-speed gearset, this is something we can look into if enough hardcore drag racers step up to request that we build one.
- Toan
We pretty much decided after the last event of the past season that our TA tC racing days would be put on hold indefinitely until we could find an affordable transmission solution. After all, we weren't about to take the power back down to 350whp just to make the transmission survive a weekend of racing.
Bottom line, if you haven't already sheared the teeth off of fourth gear or broken any other component in the transmission, most likely you're not making enough power. If you have a 400+whp tC that's seen any type of real racing action, chances are you've probably broken a transmission or two before. For the record, we've taken out fourth gear twice just on the dyno alone.
I wanted to give you guys a few technical specs on our gearset. The gears we'll be offering are forged, cryo-tempered, and shot-peened for the utmost strength and durability. After going back on forth on many gear ratios, final drive ratios, tooth profiles, straight vs. helical, and dogbox vs. syncromesh, we've finally settled on this gearset.
We knew the syncromesh engagement hub would be the weaklink at higher HP levels and not even the actual gears themselves so we decided to go with dog engagement gears. When it came to the helical vs. straight cut though, we opted to go with the helical to keep the noise levels down for street use.
This set-up provides us with a streetable, motorsports level gearbox. The dog engagement gearbox will allows you to drive the car like you stole it without being limited to how quickly the syncros want to operate.
We've selected ratios that allow for similar RPM drops between each gearshift (close-ratio) to keep the engine in the powerband for maximum performance. Also, as we all know, the factory first gear is totally useless with big power so we've selected a taller first gear to make it a usable gear.
Below are two examples of the operating range of the gears with a typical 7000rpm redline and our TA tC's 8000rpm redline.
RPM: 7000
Final Drive: 3.538
1st: 2.8 52mph
2nd: 2.083 70mph
3rd: 1.533 95mph
4th: 1.176 123mph
5th: 0.9 161mph
RPM: 8000
Final Drive: 3.538
1st: 2.8 59mph
2nd: 2.083 80mph
3rd: 1.533 108mph
4th: 1.176 141mph
5th: 0.9 184mph
To answer the question on the dedicated drag racing 4-speed gearset, this is something we can look into if enough hardcore drag racers step up to request that we build one.
- Toan
02-16-2011, 05:02 PM
#29
that was quick. Well ill definently be considering this but i wont be able to make the pre-order. Im out of funds for my car right now till the summer where ill be switching to standalone and fuel return setup. Then ill save up for this in time hopefully for the second batch next year.
02-16-2011, 05:23 PM
#30
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that was quick. Well ill definently be considering this but i wont be able to make the pre-order. Im out of funds for my car right now till the summer where ill be switching to standalone and fuel return setup. Then ill save up for this in time hopefully for the second batch next year.
02-16-2011, 06:33 PM
#32
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Wow really quick response!! I wish i could get this, but ill be there at ptuning this summer building my block. Also installing my flywheel and clutch in a few months
02-17-2011, 02:57 AM
#37
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beat you to it. my 4th gear couldnt handle m-tuned lol. got the used tranny put on already but i guess those synchros aint that good and 3rd grinds a lil but goes in smoothly. like when i go str8 to 3rd after pressing the clutch it will grind i put it in neutral press the clutch go through the gears and it wont grind. just when i am standing still and just try to go str8 into 3rd gear... 
02-17-2011, 03:18 PM
#40
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Well sinced the gears are beefed up and assuming one has a built and balanced motor... how do you guys think things will hold up with a 8500 or maybe even 9000 RPM? I ask because of this... (9k rev limit ptuning gear set & 235/40/18 tire)
1st - 66.3
2nd - 89.1
3rd - 121
4th - 157.7
5th - 206.1
1st - 66.3
2nd - 89.1
3rd - 121
4th - 157.7
5th - 206.1