kargoboy

So I was having a cup of coffee last night at Borders & reading thru this book on performance mods for Miatas (didn't have one for Pros) just to kind of get a better understanding of Mazda's engineering and maybe get some ideas. The writer was one of the original Miata engineers.
He was talking about how the first thing people ask when they join a forum is how to get more hp from the engine. He wrote that his first question back was--when do you shift gears? And went on to say that most ppl shift way too low to take advantage of the torque/hp the stock engine already puts out. So, now I'm curious...I try & shift between 4500 & 5000 rpm if traffic permits, but very rarely if ever go over 5000, even tho I know I can.
What about you folks?

macdaddyslomo

depends on how I drive...regular driving i shift at about 4K..if trying to go FAST, i shift around 5500-6000, since that is where power peaks on our cars

ibanez78

one time I was driving and I shifted pretty high up in the rpm's and when I shifted gears I must have shifted landed the rpm's in the right spot cause my car just took off. the only reason i rememer it was because my car felt like it had way more power. Felt totally different than usual shifting

Poseur

That's what redlines are indicated for. shift when it gets there and you're good. They're artificially low, and any broken-in engine should be just fine revved like it wants regularly. I honestly run WAY low RPM around town. I'm usually in 4th at 35, no need in burning the extra gas, but when I"m wantint to take off with some pep, I don't even think about shifting 'til the revs are up there. Guess I just figured that was common practice...

BlackSand

I usually try to keep my rev between 2500 and 3500 in the city.
Then on the highway shift when it reach 4500 -5000. I don't have any mods on the car yet and really don't want to screw the transmition.

How about down shifting? I never really downshift higher then 2800... I was wondering if the it damages more the engine to downshift and have it rev dramaticly from 2800 to 3500 or more depending on gear and speed?

ProDawg

Try the "heel and toe" rev matching technique and it doesn't really matter how high the revs are when downshifting. I like to go into a corner in third gear at about 30-35 and then heel and toe to blip the throttle to about 3500 rpm and downshift into second as I hit the apex of the turn and then accelerate. It takes a little practice, but it's fun and should cut down on the wear and tear on the tranny and the rest of the driveline.

kargoboy

I agree w/Dawg--best way to downshift but it does take a bit of practice.
As for damage to the tranny I don't think
that's likely but (and this is strictly hearsay) some people believe if you rev match on the downshift it does save wear on your timing belt...anyone confirm this theory? I really have no idea if it's true...

VagaBond-X

basically with my downshifting, i have figured out the speed at a certain RPM in every gear.... so if i knwo what speed i'm going, and i knwo which gear i want to goto i know where to blip the throttle too and etc etc....

basically you want it so that u can downshift 2 gears and not disrupt the cars motion at all....

so saying your going 70kmph, in 5th.... you want to downshift into second (second maxes out at about 95kmph at redline.... you will want to blip the throttle to just a little below 5500RPM and change into 2nd....
and by doing this the car wouldn't engine brake or anything, it will just be moving along liek it was in 5th, without any disruption in motion fromt he downshift...except now u'll hear the engine is alot more louder, cuz of the higher revs....

thats what you want to aim for....well thats what i aimed for and achieved back when i was learning to downshift.... heal and toe just comes naturally to me now too.... even downshifting and upshifting all comes naturally without thinkign at all....

if you have the revs matched just right you can switch gears without using the clutch....I remmeber i was doing that for a bit.... cuz we needed a new clutch so imight as well practice that on the bad clutch ... hehe


well driving for me.... i normally shift around 4000RPM - 5000RPM.... if i'm feeling alittle more spirited, then i shift at redline, or 500RPM below redline...

BlackSand

interesting, will try that tonight when no one is on the road to watch :P

rustychops41

I would caution anyone not to downshift from 2nd to 1st aggressively. Know some who auto-x their cars VERY HARD and their trannies didn't last long. It's a torqey motor anyway so I dont really see much advantage in the 2-1 downshift on 95% of auto-x courses.

BlackSand

Actually I don't know if all of u have the same thing, but I can't really shift to 1st gear unless Im almost at a complety stop state. Lets say i'm going to make a stop, I really have to make a good one to be able to shift in 1st, no american stop like we call them over here

Omron

Manually Transmission wear and tear with downshifting, thats a good question I am sure there are two answers of what it hurts and what it saves, think either way, your damned if you do and damned if you don't kinda thing, save your belts lol save your gears,

in regards to Auto, I usually shift into 2 for downshifting at Redlights, I don't utilize my gear on at all anymore, jerky start outs and fuel burning was getting to me and my wallet, honest to god 10% of my gas has come back with gradual start offs.

if your going to fast the car will not Shift down, it will shift at safe points, I think which might be 65kph, Your Car Computer should ignore any user wish to downshift at a higher speed.

Also not sure if this is true, hahha and not willing to true, but its said that Reverse will not kick in if the car is going in drive 35 kph+, sounds dumb and of course no one would try but its good to know if its true hahha..

but thats one way to bring your transmission to its knees and kill it.

VagaBond-X

yeah i think they have a lock on first gear... so that you don't go into it by accident, and just blow ure engine

but you can get into first gear very very easily

generally theres two ways to get into first.... you force it in with brute force.....

or theres my way and it just goes in nicely...

basically you rev match the engine.... then first will go in very nicely and smoothly....

okay first tops out at about 50kmph @ redline....so you guys figure out the rest of the rpms from there....

i suggest not going into first at all because it is just not needed, second should suffice for most of you guys... liek mentioned above... If first is really neccessary i recomend not going into first unless you are going 40kmph or LESS

but to get into first... rev matching it is the key.... goes easily and nicely

amrit

I don't have a tac so I don't know about the revs and well I just sorta know when to shift. I know for sure that I can't go more than about 45km/h on 1st, the car just pulls back and won't go any more until I shift into 2nd. As for downshiftin', I know that I won't shift into 1st unles I come to a complete stop or if I slow down alot like around 5km/h and I'm in 2nd and I want to pull off fast, I'd crack it into first and rip out!

rubixcubix

first gear has a lock in manual transmissions that will keep you out if you are going 20 mph or more.