RPM jump when upshifting

hadokenuh

Ok thanks a lot guys. Such a great forum

I'll try to let off the gas a sec before engaging the clutch and see if the rpm jumps.

anthonyy

Happens on 5-6 sometimes

spearfish25

If you're getting an SRM throttle blip on a 4-5 UP shift, you're being very sloppy. SRM blips under two circumstances: 1) moving horizontally across a gate in the neutral position between 5-6, 3-4 and 1-2 in a leftward direction or 2) moving 'up' into a gear within the same vertical gate (6->5, 4->3, or 2->1).

If you're in 6th with SRM on and just shift to neutral (between 3-4) you'll get a blip for 4th gear rpm. If you then push 'up' into 3rd, you'll get a second blip for 3rd gear rpm.

Shifting up the gears (1->2->3->4->5->6) should never give blips if done properly and cleanly. However, SRM will hold a proper lower RPM for an upshift if you shift very slowly. This RPM will be lower than what you had for the lower gear though so it's not a blip.

If your car is increasing RPM during an upshift (eg 4->5), you're either being sloppy with your shifting motion or your SRM is f'd up.

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2013 Cadillac V-Wagon, RIP Z

Spikuh

Very good explanation of what is going on. For anyone getting a throttle blip on up shifts, just practive making smoother shifts and it should go away.

hadokenuh

Thank you so much for all the inputs guys! Practice makes perfect.

roy'sz

i notice i get the blips too even when warmed up and am quickshifting from gear to gear. It happens all the way up to 6th, its just the ecu deceleration speed that nissan has it set to. I wonder if anyone out there who has had the ecu re flashed or uprev'd has had the deceleration rate modified? Anyone please chime in if you have had it changed and the responsiveness?

hadokenuh

Hey guys,

I am the OP and have another question: with SRM on, when I upshift not from stop but from 1-2, 2-3, etc., is it ok to let the clutch out immediately after shifting? Or should I gently clutch out?

Thanks.

roy'sz

if you drop it out it is considered "dumping" I find that when i glide it and not "dump" it my shifts and actual acceleration is better. You'll know you didn't dump it when you don't get a engine shudder

fuct

ewww roy keep the forum clean...

roy'sz

lol always!

travisjb

OP, I had the same observation/question a few years ago when this forum was pretty new... I thought, no way could this be my sloppy driving, but it was... work on the timing of how you come off the throttle vs clutch in timing... the engagement point of this clutch is different than other cars IMO and if you are coming off another manual it takes some getting used to... and btw, you can adjust the engagement point of the clutch if you continue to have problems (ie put it closer to the floor)

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2009 370Z #104
*For Sale*

hadokenuh

Thank you for the advice. I am still working on my timing and this is my first manual anyway.

Do you know if it's ok to "dump" the clutch when up-shifting from 2-3, 3-4, and so on with SynchroRev Match ON on this car? Will that damage anything?

@Roy: I don't feel any engine shudder when I clutch out. So basically, what I do is essentially clutch in - upshift - clutch out - gas. I don't have to rev match because the SRM does that for me. Is this bad?

roy'sz

srm doesn't match up shifting, i don't know why people are thinking that it does. If you aren't getting a shudder from the motor ( sounds like a f1 car going through the gears) then you are doing a good job also.

Drex

it doesn't match on upshifts but it does hold the revs from dropping too low if you're slow to shift

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2011 Nissan 370z | 6MT | Magnetic Black | Sport Package

Spikuh

Incorrect. Simply get in the car, turn on SRM, start driving and rev to 4k, shift from 1 to 2 and don't release the clutch. You will notice the RPM's do NOT drop back to idle. They hold considerably higher somewhere near 3k.

That is rev matching.

Now do the same thing except with SRM off. Notice how the RPM's drop back to idle.

That is NOT rev matching.

Also called rev matching....





Rev matching has nothing to do with downshifting or upshifting, but is simply about matching the engine rotation with the rest of the drivetrain. It just does not happen as much on the upshift because if done properly, you can basically "catch" the engine as it slows down. Done properly will allow for a smooth shift, done less than properly will provide a rougher shift.