took car for a drive today and thought id floor it.
got to the 7k mark and hearda a bleep sound,so changed gear hit 7k again and another bleep?
any ideas???
is it a rev limiter telling me to stop it lol
Lol there is a buzzer that basically says
\'for gods sake change gear\' !!!!!
seriously though thats normal the buzzer.
The RX8 has a chime lol
I could have sworn mine goes to 7500rpm...i think i killed mine cos it doesnt do it anymore...but then...the car doesnt run anymore so it doesnt count :o
might have been 7.5 not sure wasnt watching the revs that ofton
Quote from: RixioI could have sworn mine goes to 7500rpm...i think i killed mine cos it doesnt do it anymore...but then...the car doesnt run anymore so it doesnt count :o
Killed it?!?!! Oh thats a surprise!!!:rollin
When you hear that sound you just change gear, it\'s simple, no buzzer keep your foot in.:3gears-lh :D
It\'s actually dependant on where your rev limit is set. I\'ve moved mine to 8.5k so the buzzer doesn\'t come on until a bit later. In 1st and second it means it\'s time to change gear immediately but in 3rd-5th you have a little more time...
think ill leave mine where it is lol
Mine has never buzzed or chimed since I\'ve owned it.
not pushing it hard enough then lol
Oh, so that\'s the reason...:Hammer
pmsl or your more gentle and caring of your car
Quote from: WarthogWhen you hear that sound you just change gear, it\'s simple, no buzzer keep your foot in.:3gears-lh :D
Thats what I do...2 clutches and 1 gearbox so far this month.....do I need a buzzerrrrrrr:evillaugh :Giggle :rollin
i asked the same question when i first got mine and the answer was........................ that mazda put it there to say change gear because a rotary engine is so smooth, that you might not know when to change..hhhhmmmmmm.
mines buzzes once about the 7500 ish mark and changes tone when you push it that bit more to tell "please change up now!!"
Mine does it, I didn\'t think it did but then pushed a bit harder and it does... It\'s just a shame you\'re normally whizzing past any speed limits at the sound of the beep.
But speaking of rev limits, where does the ECU cut in a hard limiter? 8,000 rpm? And how safe is it to take it to the limit ona pretty standard car? My old MR2 I\'d take to 8,000 rpm in every gear, but being N/A you have to give it loads of welly just to keep it moving!
Quote from: RemarkLimaMine does it, I didn\'t think it did but then pushed a bit harder and it does... It\'s just a shame you\'re normally whizzing past any speed limits at the sound of the beep.
But speaking of rev limits, where does the ECU cut in a hard limiter? 8,000 rpm? And how safe is it to take it to the limit ona pretty standard car? My old MR2 I\'d take to 8,000 rpm in every gear, but being N/A you have to give it loads of welly just to keep it moving!
These cars seem happy with redlining BUT be careful in 4th and 5th if you\'re approaching the limiter... Not because you\'ll got to prison, lets assume you\'re doing it on a private road/runway...
In 5th approaching 7krpm you\'re doing ~150mph, maybe a little more. Your car is under peak load which increaces massively from wind resistance. Air and water temps will be rising rapidly and EGT temps will be stellar. Your turbos will be glowing!
This is a great part of the ECU\'s map to show up weaknesses and tiredness in components - fuelling. cooling, injectors, plugs, etc.
Even a well sorted motor can go pop under these conditions. Mine did a week last Sunday at 161mph and it has all the right fuelling, spark, intercooler and rad mods in place!
Puching it in 1st-3rd should be okay for most cars though!
Hitting the redline is fine. I do it all day every day in mine, its great fun.
At hitting the redline in 5th? oooer- i think that equates to over 200mph my friend. I know that you can do circa 150mph in 4th!
Interesting point Iain.....
I\'m simplifying things here, but on boingers, engine stress is said to square with revs or something like that, i.e. 8K gives a so called "stress factor" of 64 compared to 7K\'s stress factor of 49.... a massive difference.
I wonder of this is true of the rotary engine too ??
Either way I never go over 7500 rpm.....no point for me anyway my porting and turbo arent made for high revs.
Thinking of it like that, it\'s pretty impressive! To be fair, most engines can go pop at that point really ;)
But I can only think of Bedford Autodrome and Snetterton (except a few airfields) where you\'d really be hitting those speeds... Oh, and Germany ;)
Where were you doing 161 mph???
Quote from: BobfishHitting the redline is fine. I do it all day every day in mine, its great fun.
At hitting the redline in 5th? oooer- i think that equates to over 200mph my friend. I know that you can do circa 150mph in 4th!
Don\'t trust your speedo :)
Passing through timing beams at Bruntingthorp (looooong runway!) speedo was showing well over 185 and the beams read 172!
The gearing on a manual FD will hit the standard rev limiter setting ~185!
Of course and auto diff with it\'s longer ratio (3.9 opposed to 4.1) will do the trick I think!
Quote from: RemarkLimaWhere were you doing 161 mph???
Bruntinthorp proving grounds...
161 was the final (fatal run).
Managed 172 and 169 on the previous two runs.
Prior to the T70 going on the standard twins could push me to 156 before everything got too hot and they ran out of puff. With WI I reckon I could get the car to 8k rpm. Going to see if I can source an auto diff for next year! :)
Nutters, The lot of you!!!!! Cant afford to brake mine, so I\'m not going to be doing any monster driving with it....... apart from the odd 911 now and again...... his face was funny!!!!
Think the standard limiter kicks in at 8k as mine was popping & banging in second all lit up out of a junction, as there was a truck coming to get me!!!!!
Jono
Quote from: iaintIn 5th approaching 7krpm you\'re doing ~150mph, maybe a little more. Your car is under peak load which increaces massively from wind resistance.
QUOTE]
peak load is in 4th at approx 5.5 k i believe
Rmaj
Quote from: iaintBruntinthorp proving grounds...
161 was the final (fatal run).
Managed 172 and 169 on the previous two runs.
Prior to the T70 going on the standard twins could push me to 156 before everything got too hot and they ran out of puff. With WI I reckon I could get the car to 8k rpm. Going to see if I can source an auto diff for next year! :)
Wow! Impressive stuff! Shame about the engine death...
As R&S says, I wonder if the stress factor goes up? It sounds like it goes down with more revs ;)
Just done some maths based on the following numbers...
Diff ratio: 4.1:1
5th gear ratio: 0.719:1
so
Final drive: 2.9479 (diff * 5th) (a)
Tyre diameter: 25.327" (b)
RPM: 7000 (c)
MPH = (b*c) / (336 * a)
or
(25.327 * 7000) / (336 * 2.9479) = 179mph
8000rpm should give 204mph.
An auto diff (3.9:1):
7k: 188mph
8k: 215mph
Assuming ample power to get you there!
I\'ll be looking for an auto diff then as torque declines as rpm rises - one wants to be geared to maintain speed in the torque/power band.
Feed are doing a 3.7 diff at the moment.
226mph at 8k!
240mph at 8.5k!
woot!!!
You\'d need > 1000rwhp to get there though!
As I said - more interestes in the longer ratio to help me keep the rpm down when going for speed. To keep in teh peak torque band. Where did you find out abouthte feed diff? How much?
Much as I like going top speed in the FD I still find accelatration more fun. 160 is the quickest mines been (I showed that R34 lol)!! All on a runway of course.
A 3.7 diff would certainly make your acceleration a bit slower though. I\'d rather have a 4.7 and lose the top end.
Quote from: Initial-DA 3.7 diff would certainly make your acceleration a bit slower though. I\'d rather have a 4.7 and lose the top end.
Different horses and all that!
I think the ideal marriage would be a longer diff ratio and a 6-speed box!
Good for track and good for top speed! Most tracks tend to be 3rd/4th in the rex. Even silverstone\'s long streight doesn\'t really need 5th!
I think you\'d be topped out at low speed with a 4.7 diff though...
156mph @ 7k rpm as opposed to 180!
Looking at the numbers I wonder if the diameter of the wheel is wrong in my calculations because the potential speeds seem a touch high? if the diameter were smaller then the speeds would be singnificanlt slower.
See iv always wondered. If you read RX7club top speed thread they are all talking 160mph+ on lightly modded engines with 93 Ron!?! How do they get that when we arent on 98/99ron???
Im not sure about my top speed, but i was on a run with Kev yorks in his 20b and he managed 192mph on his gps & i was 3-5 car lengths behind at 6.3k rpm...so not too far off and mine isnt that highly modded. We were doing 5krpm+ for a good 10 mins on that run...all on private roads offcourse, it was the quickest run iv ever done in the RZ
Quote from: RemarkLimaI wonder if the stress factor goes up? It sounds like it goes down with more revs ;)
Sorry chaps but it definitely goes up.
Yes the motor FEELS nice and smooth when its up there. BUT you are putting a lot of stress on the Stationery gears. The Rotor spins around these gears, and the centrifugal (look it up) force gets higher and higher. The outward force of the apex seal on the housing is a problem , too. Then there is also the problem of harmonics and this can cause the throught bolts to come loose, or even break.
I would not recommend anyone go round on the rev limiter, or even the buzzer all day.
Yes, racing engines can do it, but they have the correct parts and modifications.
Yes the RX-8 can rev higher than our cars, but that is NOT the same engine.
Cheers Martin, of course that makes sense, just hoped the engine would balance well as opposed to a piston engine (where high revs require perfect balancing!)
Also with racing engines is they\'ll only be supposed to live for a few thousand miles at full power really, that\'s full on race engines!
Thing is you big turbo boys must have traction issues? An Auto diff might work well? Ive got an auto diff in mine, I think it helps me get the traction on the quarter mile?
Quote from: Initial-DMuch as I like going top speed in the FD I still find accelatration more fun. 160 is the quickest mines been (I showed that R34 lol)!! All on a runway of course.
Am sure that a serious areo package would be needed to get 200mph, or a bucket load off power and torque to pull you through the air!
This could be a new project for Ross maybe
He has a drag car, a track car and a gay (oops I mean demo ;)) car
Maybe he needs a top speed car to finish his collection !!
Ross ????
Intresting thought Mark! I remember the first run I did at Rotorstock - all I did was sit on the line spinning the tires!! Although I have rain tires on the car which offer no grip on the strip or on a dry track, only a life saver in the rain. I think if I\'d have used semi-slick or full slicks it\'d be a different story! (Probably kill the diff or drive shaft then) lol!!