Shifting smoothly

[Ultramaroon]

Originally Posted by Tcoat

I have never really paid much attention to the year of the cars where people had the most complaints but would not be at all surprised to find they are mostly 13s and early 14s.

Loose tolerances make for a cheaper build. So the TL70 is a cheap transmission. Meh. Works just fine.

[Stang70Fastback]

Originally Posted by Ultramaroon

Your first statement is incorrect. Revving the engine does nothing if the clutch is disengaged. That's my whole point.

The first gear limit ball reacts against the first gear synchro and keeps it from making contact. It's there not only to keep you from killing yourself but also to keep you from killing the synchro.

I've looked at the exploded view. I can't really make sense of exactly how it works but it's real.

What I mean is that the first gear limiter (the ball, as you describe it) that prevents you from going into that gear WILL allow you to go into first if you have the revs properly matched. You don't need to double clutch. As long as the engine speed is properly matched to the vehicle speed for first gear, the shifter will slot right into gear.

[Ultramaroon]

Originally Posted by Stang70Fastback

What I mean is that the first gear limiter (the ball, as you describe it) that prevents you from going into that gear WILL allow you to go into first if you have the revs properly matched. You don't need to double clutch. As long as the engine speed is properly matched to the vehicle speed for first gear, the shifter will slot right into gear.

I'm trying to help you understand how that statement is incorrect. You're in very good company, BTW. No shame in that.

Answer this trick/leading question. How can the engine have any affect on the input shaft of the transmission if the clutch is disengaged?

[Stang70Fastback]

Originally Posted by Ultramaroon

I'm trying to help you understand how that statement is incorrect. You're in very good company, BTW. No shame in that.

Answer this trick/leading question. How can the engine have any affect on the input shaft of the transmission if the clutch is disengaged?

I guess I was unclear when I mentioned both of these things in the same paragraph, but they were unrelated statements. Let me re-state what I was saying:

Point 1: Double clutching is meant to bring the transmission input shaft up to speed. When you double clutch, you release the clutch in neutral, which reconnects the engine to the transmission input shaft, and spins it up so that you can more easily go into the gear you are trying to go into.

Point 2 (entirely unrelated to Point 1): If you blip the throttle so that the engine has the proper RPM, you can shift into 1st at any speed.

[Ultramaroon]

Originally Posted by Stang70Fastback

I guess I was unclear when I mentioned both of these things in the same paragraph, but they were unrelated statements. Let me re-state what I was saying:

Stay with me here. I promise I'm doing this entirely in a good faith effort to be helpful. If winning is more important than understanding, that's fine. I'll move on. No harm - no worries.

Your points are related in the sense that they are contradictory.

Point 1: Double clutching is meant to bring the transmission input shaft up to speed. When you double clutch, you release the clutch in neutral, which reconnects the engine to the transmission input shaft, and spins it up so that you can more easily go into the gear you are trying to go into.

Yes, this is correct.

Point 2 (entirely unrelated to Point 1): If you blip the throttle so that the engine has the proper RPM, you can shift into 1st at any speed.

You did say this earlier. I got that each time you said it. It's incorrect and you explained why in point 1.

Originally Posted by Stang70Fastback

What I mean is that the first gear limiter (the ball, as you describe it) that prevents you from going into that gear WILL allow you to go into first if you have the revs properly matched. You don't need to double clutch. As long as the engine speed is properly matched to the vehicle speed for first gear, the shifter will slot right into gear.

If your clutch is disengaged and you're in neutral then the driveline is split into three sections; the engine, the transmission input side, and everything else from the output to the rear wheels.

The first gear limit depends on the input side spinning close enough to the output side before it allows the two (three, actually) parts of the synchro to come into contact.

No amount of revving the engine will do anything in this case. Your friend is wrong and you've been experiencing a placebo effect. Many many years ago before I really thought it through, I used to do the same thing.

[Stang70Fastback]

Originally Posted by Ultramaroon

If your clutch is disengaged and you're in neutral then the driveline is split into three sections; the engine, the transmission input side, and everything else from the output to the rear wheels.

The first gear limit depends on the input side spinning close enough to the output side before it allows the two (three, actually) parts of the synchro to come into contact.

No amount of revving the engine will do anything in this case. Your friend is wrong and you've been experiencing a placebo effect. Many many years ago before I really thought it through, I used to do the same thing.

I totally understand what you are saying, and I don't disagree with anything you just said. I'm not trying to be argumentative. I guess I was still being unclear because I forgot to mention one important piece of information: I have NO idea why matching the engine speed makes a difference in whether or not the car allows me to shift into 1st. I simply know that it does. I can try to jam the shifter into first all I want, but it won't happen. The moment I get the engine up to the proper speed (with the clutch still depressed) the shifter slots into gear. This isn't a placebo effect. It's an actual physical phenomenon that is happening.

I would love for someone to explain why this is the case, because everything you said is true, and so it seems contradictory to my actual experience. I'm not disagreeing with you. I'm simply telling you how my car is actually functioning. How else do you explain the video above? It isn't "faked." All I did was blip the throttle and it went right into gear at 20 MPH. If I hadn't blipped the throttle, it would not have gone into gear.

My impression is that there is a mechanical system in the vehicle that prevents you from putting the shifter into 1st gear unless your engine speed is closely matched. That's what it seems like, anyway.

[cjd]

Given that you don't need the clutch if you rematch properly, I'm guessing the clutch engages a tiny bit before the shift happens.

[Ultramaroon]

Originally Posted by Stang70Fastback

Okay, I see the point you are making. I'm not trying to be argumentative. I guess I was still being unclear because I forgot to mention one important piece of information: I have NO idea why matching the engine speed makes a difference in whether or not the car allows me to shift into 1st. I simply know that it does. I can try to jam the shifter into first all I want, but it won't happen. The moment I get the engine up to the proper speed (with the clutch still depressed) the shifter slots into gear. This isn't a placebo effect. It's an actual physical phenomenon that is happening.

I would love for someone to explain why this is the case, because everything you said is true. I'm not disagreeing with you there. I'm simply telling you how the system behaves through my experiences. How else do you explain the video above? It isn't "faked." All I did was blip the throttle and it went right into gear at 20 MPH. If I hadn't blipped the throttle, it would not have gone into gear.

I have a theory but you would have to test on a cold morning. If your technique works just as well first thing in the morning then I have no explanation.

If there is any difference, doesn't work quite as well or not at all, then I'll say there is just enough drag from the air gap or some light contact between the disc and flywheel/pressure plate to do the job.

And I didn't get the impression you were being argumentative. I just wanted to assure you I had no intention of being "that guy."

[Ultramaroon]

Originally Posted by cjd

Given that you don't need the clutch if you rematch properly, I'm guessing the clutch engages a tiny bit before the shift happens.

Yeah, this ^^^

Definitely not my experience.

[humfrz]

Well, this will give me something to do in the morning ...... see if/how I can get my FR-S into first gear when it is moving.

If I remember to try it ....... then remember how I did it .......



humfrz

[Ultramaroon]

Originally Posted by Stang70Fastback

The moment I get the engine up to the proper speed (with the clutch still depressed) the shifter slots into gear. This isn't a placebo effect. It's an actual physical phenomenon that is happening.

Tried it again this morning in earnest. It works. I struggled with it but I think if I didn't know any better and just practiced, I'd nail it. Looks like with the pressure plate rattling around in there, there's just enough contact to do the trick.

I didn't try it stone cold because I didn't think of it early enough this morning.

[Stang70Fastback]

Originally Posted by Ultramaroon

Tried it again this morning in earnest. It works. I struggled with it but I think if I didn't know any better and just practiced, I'd nail it. Looks like with the pressure plate rattling around in there, there's just enough contact to do the trick.

I didn't try it stone cold because I didn't think of it early enough this morning.

Yeah. Like I said, not sure WHY it works, but it does, lol. Are we sure there isn't a mechanical lockout that is linked to engine RPM somewhere in there? I'm not familiar with the mechanics under there.

[Ultramaroon]

Originally Posted by Stang70Fastback

Yeah. Like I said, not sure WHY it works, but it does, lol. Are we sure there isn't a mechanical lockout that is linked to engine RPM somewhere in there? I'm not familiar with the mechanics under there.

On that, I'm 100% positive. Try it stone cold when there's more drag on everything. Without going into detail on why, the cold thick lube has more effect on the input side than it does on the output.

I'll try it as well.