citka Posted January 22, 2012 Share Posted January 22, 2012 The clutch is just about done in my OB. It's giving the tell-tale signs where it starts slipping at higher speeds, in 5th gear. I've heard this reported from multiple people and my car is no different. My confusion is this: Every other manual transmission I've ever had exposure to with a failing clutch, the slippage comes down low in the speed and in lower gears. For instance, I'm used to the clutch slipping from a stoplight or similar. It slips until the car builds speed, then catches up with the motor RPM. Why is the Subaru setup different? Link to comment Share on other sites More sharing options...
LosAngelesLGT Posted January 23, 2012 Share Posted January 23, 2012 Its not any different. It has not failed that much YET. It will. Keep driving it if you want to see for yourself. 5th gear slipping under power is just the first sign. 4th and 3rd as well as low gears under throttle is next. Link to comment Share on other sites More sharing options...
iNVAR Posted January 23, 2012 Share Posted January 23, 2012 Because in higher gears is when the engine is under the heaviest load. Link to comment Share on other sites More sharing options...
citka Posted January 23, 2012 Author Share Posted January 23, 2012 How is that different from other cars though? Link to comment Share on other sites More sharing options...
underground000 Posted January 23, 2012 Share Posted January 23, 2012 its the turbo 5eat downshift rev match:) Powder coated wheels: completed:) Link to comment Share on other sites More sharing options...
johnAWD Posted January 23, 2012 Share Posted January 23, 2012 The Subaru isn't different than other cars when it comes to the clutch. It'll slip, then slip a bit more, then slip a lot. Link to comment Share on other sites More sharing options...
underground000 Posted January 23, 2012 Share Posted January 23, 2012 saw a mustang on the dyno and it slipped at high rpms not at low OP has user problems:lol: 5eat downshift rev match:) Powder coated wheels: completed:) Link to comment Share on other sites More sharing options...
Max Capacity Posted January 23, 2012 Share Posted January 23, 2012 It has to do with the higher load and longer duration. I guess you've never seen a RWD drag car snap a driveshaft in 3rd gear in the 1/4 mile. 305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD). CHECK your oil, these cars use it. Engine Build - Click Here Link to comment Share on other sites More sharing options...
BAC5.2 Posted January 23, 2012 Share Posted January 23, 2012 This must be a troll thread. [URL="http://legacygt.com/forums/showthread.php/proper-flip-key-interesti-159894.html"]Flip Key Development Thread[/URL] "Genius may have its limitations, but stupidity is not thus handicapped." - E. Hubbard Link to comment Share on other sites More sharing options...
Max Capacity Posted January 23, 2012 Share Posted January 23, 2012 This must be a troll thread. LOL kind of slow here at the old factory today... 305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD). CHECK your oil, these cars use it. Engine Build - Click Here Link to comment Share on other sites More sharing options...
SSpeed Posted January 23, 2012 Share Posted January 23, 2012 Why at higher rpms? Where is the peak torque? http://i85.photobucket.com/albums/k62/dil222/BoostCreep16g115correctedsspeedresize.jpg Link to comment Share on other sites More sharing options...
citka Posted January 23, 2012 Author Share Posted January 23, 2012 OP is probably a dumb ass, but the OP grew up with muscle cars. He's used to seeing torque curves similar to above, just bigger numbers. Even so, clutches have always slipped on the OP at low speeds, low RPM's before they do at freeway speeds when overtaking in 5th gear. Link to comment Share on other sites More sharing options...
Mega Users seabass07 Posted January 23, 2012 Mega Users Share Posted January 23, 2012 Citka, if you want a hand fixing that clutch, let me know. You build up more boost in 5th. Especially over an extended time at higher speeds. So more torque in a higher gear. Like others said, you will eventually get the slipping in 4th then 3rd. Link to comment Share on other sites More sharing options...
SSpeed Posted January 23, 2012 Share Posted January 23, 2012 Cool, bear in mind the number above is at 5400' and about what the new Camaros see here as well.. It's not so much the torque curve that makes it happen, it's that the torque comes on very abruptly and in a short period of time. If that clutch is just hanging on, that's when it will let go. In muscle cars, which I also grew up with, the torque curve is never as abrupt, you never have the shock to the clutch once you're in the powerband that you do with a turbo. Link to comment Share on other sites More sharing options...
citka Posted January 23, 2012 Author Share Posted January 23, 2012 ^^ Thanks to SSPeed for the detail I was needing. Makes sense now. Link to comment Share on other sites More sharing options...
citka Posted January 23, 2012 Author Share Posted January 23, 2012 SeaBass - Thanks for the offer. This will be LGT clutch #6 (1st for my car) I've installed. It's pretty much routine now. Last one we did in just over 3 hours including a pizza and beer break. Link to comment Share on other sites More sharing options...
iNVAR Posted January 24, 2012 Share Posted January 24, 2012 I don't think it's just the amount of torque at high RPM or gear or load. It's the fact that there's resistance to that torque being applied. In other words, when you're in lower gears and/or speeds, the power from the engine is transferred through the clutch and then to the ground and your car readily accelerates forward. But in higher gears and speed, it is more difficult to accelerate. There's resistance, so the clutch can slip as a result. I think.... Link to comment Share on other sites More sharing options...
underground000 Posted January 24, 2012 Share Posted January 24, 2012 I don't think it's just the amount of torque at high RPM or gear or load. It's the fact that there's resistance to that torque being applied. In other words, when you're in lower gears and/or speeds, the power from the engine is transferred through the clutch and then to the ground and your car readily accelerates forward. But in higher gears and speed, it is more difficult to accelerate. There's resistance, so the clutch can slip as a result. I think.... yes, there is higher load on the engine... same thing as you just described one reason why you can hit full boost in 5th and not 1st 5eat downshift rev match:) Powder coated wheels: completed:) Link to comment Share on other sites More sharing options...
SSpeed Posted January 24, 2012 Share Posted January 24, 2012 Hmm, I think it probably takes more to get moving from a stop than it does to accelerate while rolling? Once on the highway you're right, there's more resistance in higher gears. Part of the reason we don't hit full boost in 1st is the tuning aspect of it... With a manual boost controller you can definitely hit full boost in first.. the gear ratios will dictate the load and it will be at a higher rpm.... Link to comment Share on other sites More sharing options...
underground000 Posted January 24, 2012 Share Posted January 24, 2012 I don't think it's just the amount of torque at high RPM or gear or load. It's the fact that there's resistance to that torque being applied. In other words, when you're in lower gears and/or speeds, the power from the engine is transferred through the clutch and then to the ground and your car readily accelerates forward. But in higher gears and speed, it is more difficult to accelerate. There's resistance, so the clutch can slip as a result. I think.... yes, there is higher load on the engine... same thing as you just described one reason why you can hit full boost in 5th and not 1st haha i didnt quite read the first part, i resaid what invar said lol 5eat downshift rev match:) Powder coated wheels: completed:) Link to comment Share on other sites More sharing options...
underground000 Posted January 24, 2012 Share Posted January 24, 2012 Hmm, I think it probably takes more to get moving from a stop than it does to accelerate while rolling? Once on the highway you're right, there's more resistance in higher gears. Part of the reason we don't hit full boost in 1st is the tuning aspect of it... With a manual boost controller you can definitely hit full boost in first.. the gear ratios will dictate the load and it will be at a higher rpm.... it takes less, the engine is spinning over 3x faster then the transmission in 1st and from a stop you are 'slipping'/ barely engaging the clutch to get the car moving. so you are not 100% engaged from the engine and transmission 5eat downshift rev match:) Powder coated wheels: completed:) Link to comment Share on other sites More sharing options...
SSpeed Posted January 24, 2012 Share Posted January 24, 2012 it takes less, the engine is spinning over 3x faster then the transmission in 1st and from a stop you are 'slipping'/ barely engaging the clutch to get the car moving. so you are not 100% engaged from the engine and transmission Perhaps.. my thought process on this was silly, if you have a BIG round rock, what's tougher, getting it moving or speeding up a bit once it is moving.. obviously you have no gear ratios when pushing a rock.. Link to comment Share on other sites More sharing options...
BAC5.2 Posted January 24, 2012 Share Posted January 24, 2012 Is this thread still going? Gear ratios multiply torque, right? If you have a 2:1 ratio, you are multiplying the torque by 2. So in higher gears, when the gear ratios dip below 1:1, what do you have? Torque division. So now, instead of having a surplus of torque in which to accelerate the vehicle, you have a deficit. That requires greater throttle opening and more power to be able to accelerate the vehicle. Where in a lower gear, you could just barely crack the throttle to acheive the necessary torque to move forward, in a higher gear you have to open it up proportionally more to deliver the same torque to the wheels. Couple that with the power demands of accelerating at speed (power requirement increases to the cube of vehicle speed), and you can see where this is going. Clutch slips in higher gears. In no way, whatsoever, do Muscle cars experience the opposite. Nail it in 1st, and nail it in 5th. The clutch will slip in 5th first. That's the old test they told you in the 70's to find out if your clutch was slipping. Put it in the highest gear you have, and nail the throttle. If it doesn't slip, it's not slipping. [URL="http://legacygt.com/forums/showthread.php/proper-flip-key-interesti-159894.html"]Flip Key Development Thread[/URL] "Genius may have its limitations, but stupidity is not thus handicapped." - E. Hubbard Link to comment Share on other sites More sharing options...
iNVAR Posted January 24, 2012 Share Posted January 24, 2012 Heheh maybe the OP was thinking of WHEEL spin in first in a muscle car. That's what it sounds like he's talking about! Link to comment Share on other sites More sharing options...
Max Capacity Posted January 24, 2012 Share Posted January 24, 2012 Is this thread still going? QUOTE] What he said! 305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD). CHECK your oil, these cars use it. Engine Build - Click Here Link to comment Share on other sites More sharing options...
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