Anyone experience a weird issue when rev matching into 2nd sometimes?

Not sure if this is a common problem or not, but if I try to blip the throttle at the same time while downshifting from 3rd to 2nd, I get this weird "partial throttle" sound. Like as opposed to blipping 1-2k RPMs higher, it seems like only a little of the throttle blip is registered.

The only way I can successfully do it is to clutch in, blip while in 3rd, and then downshift to 2nd. Trying to blip simultaneously while going down to 2nd results in a very small (maybe 200 rpm) blip -- again, like only half of it is registered or something.

I'll try to get a video going today, but figured I'd make a post already to see if anyone else knows what I'm talking about.

No issue here. Is this on the street or track?

altjx said:

Not sure if this is a common problem or not, but if I try to blip the throttle at the same time while downshifting from 3rd to 2nd, I get this weird "partial throttle" sound. Like as opposed to blipping 1-2k RPMs higher, it seems like only a little of the throttle blip is registered.

The only way I can successfully do it is to clutch in, blip while in 3rd, and then downshift to 2nd. Trying to blip simultaneously while going down to 2nd results in a very small (maybe 200 rpm) blip -- again, like only half of it is registered or something.

I'll try to get a video going today, but figured I'd make a post already to see if anyone else knows what I'm talking about.

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Same thing here, although I'm not even sure I know what I'm doing, so... LOL

TDC said:

No issue here. Is this on the street or track?

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Just on the street. Haven't taken it to the track yet. So just for clarification though, you can blip while simultaneously going into 2nd from 3rd? No issues? Hope this isn't any beginning to a crazy problem or anything for me.

04Terminator said:

Same thing here, although I'm not even sure I know what I'm doing, so... LOL

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LOL.

CSL said:

Are you blipping twice without releasing the clutch in 3rd?

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I'm doing the same thing from every gear. Clutch in, blip + downshift (same time), clutch out. However, from 3rd to 2nd is where I get a different result. Nothing blipping twice or anything.

When decreasing speed for a turn for example I'll shift from 3rd to 2nd as follows:
clutch in, braking and rolling my foot brake onto the accelerator to blip it, then downshift.

blip

altjx said:

Not sure if this is a common problem or not, but if I try to blip the throttle at the same time while downshifting from 3rd to 2nd, I get this weird "partial throttle" sound. Like as opposed to blipping 1-2k RPMs higher, it seems like only a little of the throttle blip is registered.

The only way I can successfully do it is to clutch in, blip while in 3rd, and then downshift to 2nd. Trying to blip simultaneously while going down to 2nd results in a very small (maybe 200 rpm) blip -- again, like only half of it is registered or something.

I'll try to get a video going today, but figured I'd make a post already to see if anyone else knows what I'm talking about.

Click to expand...

Your blipping too late or short. Your timing is off. The RPM's have to be properly matched and the shift between gears crisp, not slo mo.

I downshift to 2nd a lot, and its clutch in then blip while shifting into 2nd, no problem.

TDC said:

When decreasing speed for a turn for example I'll shift from 3rd to 2nd as follows:
clutch in, braking and rolling my foot brake onto the accelerator to blip it, then downshift.

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Gotcha, so not blipping and shifting simultaneously? I found that I have zero problems if I do it the way you describe. I'm not sure why I've only noticed this from 3rd to 2nd though. Maybe since it's a little tougher to get into 2nd than it is from 5th to 4th, considering it's not just really a straight pull back.

RadBOSS said:

Your blipping too late or short. Your timing is off. The RPM's have to be properly matched and the shift between gears crisp, not slo mo.

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The problem is that I can't blip during this situation. What I mean by this is clutching in and blipping while simultaneously going into 2nd from 3rd is essentially the same as clutching in and going straight to 2nd from 3rd. Something weird in this process happens where the throttle blip doesn't work. It's like hitting the accelerator hard (for a +2000 RPM blip) and it goes up 200 RPM and drops back down.

Shift said:

I downshift to 2nd a lot, and its clutch in then blip while shifting into 2nd, no problem.

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I couldn't reproduce it today for some reason while I had my GoPro recording, but it's very weird how it only happens sometimes. Trying to pinpoint specifically what's going on.

Thanks for the feedback though guys. Sounds like I may just be doing something wrong.

You might want to look at a gas pedal pad extension cover. Then when trying to blip while braking before you down shift its not as awkward to push or roll your foot over both pedals.

Photo attached is what I had on my 05 Mustang GT

I offer this as help, not an attack, so please take this the right way. But it sounds like user error.

Having done a lot of on track instruction is it very common to see drivers have a problem with the 3rd-2nd downshift when they are able to do the others smoothly. My theory is that the shift into second happens under heavier braking, causing the driver to rush the process while simultaneously increasing the need for a more perfect shift from a mechanical perspective.

I had the same problem myself in a 2001 Boxster S when I was just beginning to learn to heel/toe on track a dozen years ago. I thought there was a problem with the car until my instructor got behind the wheel and suddenly it was fixed. Maybe see if you can get someone else behind the wheel and see if the problem still exists?

I think there may be a misunderstanding here. I'm not having problems heel toe downshifting. In my case I'm not even using the brakes at all. I'm just simply downshifting as I'm coming to a red light and letting the car brake on its own.

If approaching a red light and coasting to a stop, why are you downshifting and blipping at all? Seems like the end state is the car in neutral and sitting at a complete stop. No need to downshift and blip.

Blipping is done when downshifting to achieve the correct gear so that acceleration can occur immediately upon the release of the brake. You are simply trying to match the engine speed to the car's actual speed, so that you can shift gears prior to when that match would occur naturally at slower road speeds.

In the situation you are describing the synchros should be doing the work for you, no need to blip. If you need to blip in your situation, you are using engine braking to stop the car, which creates wear on expensive parts. Let the brakes do the work for you to slow down in those situations.

jakermc said:

If approaching a red light and coasting to a stop, why are you downshifting and blipping at all? Seems like the end state is the car in neutral and sitting at a complete stop. No need to downshift and blip.

Blipping is done when downshifting to achieve the correct gear so that acceleration can occur immediately upon the release of the brake. You are simply trying to match the engine speed to the car's actual speed, so that you can shift gears prior to when that match would occur naturally at slower road speeds.

In the situation you are describing the synchros should be doing the work for you, no need to blip. If you need to blip in your situation, you are using engine braking to stop the car, which creates wear on expensive parts. Let the brakes do the work for you to slow down in those situations.

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Hmm, very interesting. If I don't blip, the car pretty much brakes harder the more I let out of the clutch. Conversely, blipping makes it smooth. I don't do this at every red light, but only when I know the light is about to turn green again, so I'll downshift as I approach the light and by the time the light turns green, I'm already in the appropriate gear and can just accelerate. If I know I'll be sitting for awhile, I just throw it in neutral and coast to the red light, and then brake. Is this bad practice?

altjx said:

Not sure if this is a common problem or not, but if I try to blip the throttle at the same time while downshifting from 3rd to 2nd, I get this weird "partial throttle" sound. Like as opposed to blipping 1-2k RPMs higher, it seems like only a little of the throttle blip is registered.

The only way I can successfully do it is to clutch in, blip while in 3rd, and then downshift to 2nd. Trying to blip simultaneously while going down to 2nd results in a very small (maybe 200 rpm) blip -- again, like only half of it is registered or something.

I'll try to get a video going today, but figured I'd make a post already to see if anyone else knows what I'm talking about.

Click to expand...

I never noticed that. Its possible the the computer isnt accepting the throttle input for some reason (emissions or something)

Are you sure the clutch is fully depressed when you Blip it?