Rev Matching: Gear Ratios and RPMs
#1
Handy Rev Matching Diagram
Hi all,
I couldn't find any info on rev matching with our gear ratios, so I thought I'd contribute by doing a few calculations.
The following info shows what your next RPM will be if you shift at 9000RPM.
1->2: 60.346% (5431 RPM)
2->3: 72.499% (6525 RPM)
3->4: 72.158% (6494 RPM)
4->5: 84.246% (7582 RPM)
5->6: 84.300% (7587 RPM)
For example, in the first line (1->2: 60.346% (5431 RPM)), what this means is that if you shift at 9000RPM from 1st to 2nd gear, your RPM will land at around 60.346% of 9000RPM, which is 5431RPM
I'm attaching a handy diagram of frequently used upshift and downshift sequences on the RX-8. I hope you find this useful in your efforts to simulate a DSG! Please note that I rounded the numbers for easy absorption.
DISCLAIMER: Keep your eyes on the road and not the tachometer. I won't be responsible for anything that happens as a result of someone using this information.
I couldn't find any info on rev matching with our gear ratios, so I thought I'd contribute by doing a few calculations.
The following info shows what your next RPM will be if you shift at 9000RPM.
1->2: 60.346% (5431 RPM)
2->3: 72.499% (6525 RPM)
3->4: 72.158% (6494 RPM)
4->5: 84.246% (7582 RPM)
5->6: 84.300% (7587 RPM)
For example, in the first line (1->2: 60.346% (5431 RPM)), what this means is that if you shift at 9000RPM from 1st to 2nd gear, your RPM will land at around 60.346% of 9000RPM, which is 5431RPM
I'm attaching a handy diagram of frequently used upshift and downshift sequences on the RX-8. I hope you find this useful in your efforts to simulate a DSG! Please note that I rounded the numbers for easy absorption.
DISCLAIMER: Keep your eyes on the road and not the tachometer. I won't be responsible for anything that happens as a result of someone using this information.
Last edited by dynamho; 07-20-2006 at 02:17 PM.
#2
Thanks dynamho for the great info. This is great for drivers who currently don't rev-match their downshifts and should learn. I'm still trying to fine-tune my rev-matching by gut feeling and am experimenting with double clutching (it's hard!).
#4
Originally Posted by lshu
Thanks dynamho for the great info. This is great for drivers who currently don't rev-match their downshifts and should learn. I'm still trying to fine-tune my rev-matching by gut feeling and am experimenting with double clutching (it's hard!).
Ishu, it would be easier if you clutch in > rev match > shift into desired gears > clutch out.
this is easier then double clutching.
#6
it isn't necessary but if you do it right, it's fine. double clutching just takes longer to do and with our syncros, we don't need to.
thanks for the chart dynamho. i do believe your data is good from my observations while shifting as well.
thanks for the chart dynamho. i do believe your data is good from my observations while shifting as well.
#7
I'm new at the matching revs thing, but it's pretty fun to mess around with. Has anyone noticed that in 3rd gear, the revs match the MPH exactly?!?! So, if you're in 4th gear going 60 and you want to downshift to 3rd, the revs in 3rd gear would be 6000. If you're going 79 in 3rd gear, the revs would be just a hair under the 8000 mark. It makes it really easy to downshift to third for more power or to help with breaking!
I'm not a math wizard, but do the numbers dynamho posted agree with what i noticed??
I'm not a math wizard, but do the numbers dynamho posted agree with what i noticed??
#8
Great insite Dynamho!
Double clutching is not necessary on our cars. Really no benefit.
If a person feels it is better it is only because the RPMs have came down because of the time it takes to push the pedal down twice before shifting...
Waiting a touch longer in between shifts will do the same thing.
Double clutching is not necessary on our cars. Really no benefit.
If a person feels it is better it is only because the RPMs have came down because of the time it takes to push the pedal down twice before shifting...
Waiting a touch longer in between shifts will do the same thing.
#9
I don't know if anybody else does this, but blipping the rev/throttle then shifting into the desired gear is something to do as well. For example,if your doing 65mph in 6th gear, and you need to pass or accelerate pretty quickly, blip the throttle and shift into 3rd. You will find out that the gears will engage a tad quicker and they will grab at a slightly higher rpm, then just normal shifting and losing revs.
Its funky to do at first , but with practice it can be executed to a tee! Since i do it all the time , its like second nature to me, almost feels weird not to do it.
Results = quicker down shifts at highway speed
Its funky to do at first , but with practice it can be executed to a tee! Since i do it all the time , its like second nature to me, almost feels weird not to do it.
Results = quicker down shifts at highway speed
#10
Originally Posted by DailyDriver2k5
I don't know if anybody else does this, but blipping the rev/throttle then shifting into the desired gear is something to do as well. For example,if your doing 65mph in 6th gear, and you need to pass or accelerate pretty quickly, blip the throttle and shift into 3rd. You will find out that the gears will engage a tad quicker and they will grab at a slightly higher rpm, then just normal shifting and losing revs.
Its funky to do at first , but with practice it can be executed to a tee! Since i do it all the time , its like second nature to me, almost feels weird not to do it.
Results = quicker down shifts at highway speed
Its funky to do at first , but with practice it can be executed to a tee! Since i do it all the time , its like second nature to me, almost feels weird not to do it.
Results = quicker down shifts at highway speed
#12
yes third is one for one rpm to mph. i never shift from 6th to 3rd. i trry to think a few moves furthur ahead than the need for that. when i decide i want to pass i move it to 4th. this is well before i have an opening. gets the revs in to the power in the first place. then i watch for the openign i see coming up and when it opens i shift to third and hammer the throttle.
#13
You're so kind to your transmission.
I agree that seeing ahead and planning ahead is a deliberate and acquired skill. Most people on the road, in contrast to you, seem to have a 100 feet reaction distance. They react only when things are right on them.
Car drivers may learn a lot from motorcycle riding safety courses, where they teach you situational awareness, to look way ahead, to consciously be aware of events in your peripheral vision, and to frequently scan who's creeping up behind and beside you.
Taking all these into consideration, I believe that anyone can become a much smoother driver on the road. I'm guessing that zoom44 is one of those who practices this style of driving.
I agree that seeing ahead and planning ahead is a deliberate and acquired skill. Most people on the road, in contrast to you, seem to have a 100 feet reaction distance. They react only when things are right on them.
Car drivers may learn a lot from motorcycle riding safety courses, where they teach you situational awareness, to look way ahead, to consciously be aware of events in your peripheral vision, and to frequently scan who's creeping up behind and beside you.
Taking all these into consideration, I believe that anyone can become a much smoother driver on the road. I'm guessing that zoom44 is one of those who practices this style of driving.
Originally Posted by zoom44
yes third is one for one rpm to mph. i never shift from 6th to 3rd. i trry to think a few moves furthur ahead than the need for that. when i decide i want to pass i move it to 4th. this is well before i have an opening. gets the revs in to the power in the first place. then i watch for the openign i see coming up and when it opens i shift to third and hammer the throttle.
#15
Yeah, for a while I've been meaning to post something like this, but wanted to make sure my numbers are correct. But from memory, since the engine produces such linear power, I think each additional 1000 rpm is worth:
1st - 6 mph
2nd - 9 mph
3rd - 11mph (not 10. 3300rpm = 30mph)
4th - ? (forget)
5th - ? (forget)
6th - 20 mph
I think of these as multipliers to help me easily calculate approximately what rpm I'll need for any given gear and speed. It sort of starts to break down around 7k rpm (you do not get 180mph at 9000 rpm in 6th), but it's a rough guide. Feel free to correct me on these.
1st - 6 mph
2nd - 9 mph
3rd - 11mph (not 10. 3300rpm = 30mph)
4th - ? (forget)
5th - ? (forget)
6th - 20 mph
I think of these as multipliers to help me easily calculate approximately what rpm I'll need for any given gear and speed. It sort of starts to break down around 7k rpm (you do not get 180mph at 9000 rpm in 6th), but it's a rough guide. Feel free to correct me on these.
#17
You're absolutely right, but from my point of view, it arguably takes greater effort to match (6 to 3) than (6 to 4 then 4 to 3). There's more chance for error and the result of that error is more stress on the transmission.
Your comment is applicable to well executed shifts, in which case, even 3 to 1 is fine. My comment is more focused on probability for error and what this error can do to your tranny.
Your comment is applicable to well executed shifts, in which case, even 3 to 1 is fine. My comment is more focused on probability for error and what this error can do to your tranny.
Originally Posted by LostAngel
I don't see how thats bad for the transmission? As long as you rev match when shifting to 3rd...it should be easy on it shouldn't it?
#22
Hard to believe but I have driven manuals for about 15 of my 19 years behind the wheel an only in the past year did I find out you should blip the throttle when shifting gears. No one taught me how to drive a stick I was just handed the keys to my first manual car and told to figure it out (probably didn’t help that it was a 79 Yota pickup and my next was a 92 Ford Escort). Which I did but obviously there are some finer points to operating 3 pedals that you can always learn.