Rev Matching Accuracy and Affects on Tranny and Clutch

[santorex]

So I've had my 13 rex now for about 4 months and had some questions around rev matching and looking for others experiences rev match downshifting. I know there are other threads on rev matching, but I haven't really seen anything specifically on the accuracy of the blip...

When I rev match (to slow down for a highway off ramp for example) I don't double clutch, just clutch in, blip throttle, and clutch out. Most of the time I get within 200 RPM. Is this good? Should I be looking to be more accurate? Most of the time I over blip slightly on purpose, and then catch the RPM as it's dropping (similar to upshifting). Sometimes it's perfect which is great feeling... and sometimes I totally miss.

My main questions:

• Is being ~200 RPM off the majority of the time on each rev match a reasonable rev match? Or is it realistic to be getting perfect rev matches all the time with more practice?
• What is considered a good rev match? My current benchmark is if my passengers can only tell I shifted because I move the shifter, but there's no jolt.
• Will being off put too much wear on the synchros/clutch?
• Is it better to overshoot or undershoot with the blip? I've heard both...

Thanks for the input!

[Soobvirgin]

Umm... you may be over-thinking this a little.

[11blackSTi]

Been driving manual transmission cars for almost 15 years and have never had issues with my clutch or transmission and I downshift without perfect rev matches a lot. I have always thought of this as engine breaking, not breaking engine haha.

This is only my personal experience, although I am sure there are others that have had issues which they might say was due to downshifting.

[Ruh Roh]

as you let the clutch out dont fully release it very quickly, you can tell if its a little bit off the perfect match and kinda slip the clutch a bit if you overshoot the rpms

[santorex]

Okay thanks for the replies guys. Overthinking's my thing Just wanted to make sure I was doing reasonably well.

Instead of a blip, I've also tried to hold the throttle where it is and slowly raise to where it needs to be for the lower gear. Sometimes this works, but I think I like the blip approach better.

[Ruh Roh]

yea a quick blip does the trick

[RayfieldsWRX]

The conventional wisdom on both car and motorcycle sites that I've read is that "brake wear is cheaper than clutch wear". I blatantly disregard this, because I really enjoy shifting down. I do try to rev match, though I don't know how precisely, really. I get really good life out of my clutches, so :shrug:

[EndlessSea]

Umm... you may be over-thinking this a little.

^ ^
this
except change a little to a LOT. your over-thinking this a lot man. rev match if it makes you feel good, dont if it doesnt. as long as your not abusing it, any modern manual transmission will last for hundreds of thousands of miles. the only thing your going to wear out faster by rev matching/not rev matching it is your clutch....

[chutoyy]

If you blip the throttle enough so that there's minimal to no lurching or lunging of the car, you should be fine. I've seen people just slam into a lower gear and pop the clutch. :shudder:

Try heel-toeing on streets. :P

[SD_GR]

If you learn to shift on a bike it's simpler: if you're still upright you shifted OK.

Just drive the car reasonably, most of this stuff is a waste of time.

[Ruh Roh]

If you learn to shift on a bike it's simpler: if you're still upright you shifted OK.

Just drive the car reasonably, most of this stuff is a waste of time.

nothing like locking up the back tire from an improper down shift

[RayfieldsWRX]

If you learn to shift on a bike it's simpler: if you're still upright you shifted OK.

Yep, a bike will teach you all sorts of things...setting entrance speed into a curve correctly comes to mind.
Also, it's not good to shift down to 1st when you think you're shifting down to 2nd...rev your CBR600 to 8000rpms, and pop the clutch. I, um, found out about that one.
"Oh, lookee there...it's the sky...perty..."

[chutoyy]

I Lol'd... I've done the same to my F4i.

But yeah, all the new cars have synchros for a reason.

Yep, a bike will teach you all sorts of things...setting entrance speed into a curve correctly comes to mind.
Also, it's not good to shift down to 1st when you think you're shifting down to 2nd...rev your CBR600 to 8000rpms, and pop the clutch. I, um, found out about that one.
"Oh, lookee there...it's the sky...perty..."

[Sheleileigh Law]

Downshift and rev match by feel...

[Mr2012WRX]

It's seems silly to do rev matching on turbo cause you have to wait till it spool. otherwise you are just costing more $$ later. I used to do it a lot with my RSX - S when I had her back in the ole days. Love iit on natural aspirated engine.