brandon's rx-7

i have a 86 n/a with apexi n1 racing exhaust with bonez race pipe. it is street ported and i have a bonez air intake. i was wondering when i race what rpm should i shift at for best performance. and when iam just driving around what should i shift at. i have been doing it at 4k is that to high to low or just perfect. the only reason y iam asking is b/c i just got it rebulit it has 5,000 miles on it. i dont want to rev it to high but its a rotary it has to be reved high every time i take it to 5k iam afraid of over doing it. some one post a message that they rev at 6k all the time and there rx has tons of miles and still runs fine

eViLRotor

iTrader: (2)

For 'regular' driving, shifting at 4000 rpm is fine. At least you are shifting high enough for your secondary injectors to come on.

For 'fast' driving, you want to shift at a point where when the revs drop back down, you are at or slightly below your peak torque rpm.

I'm not sure at what rpm that is on a S4, but its not hard to find out....

At the track I take my TII to 7000-7500 quite frequently. I rev my 85 GSL-SE at 5000 all day

Black13B

iTrader: (1)

If yours is a rebuild, you should keep the revs down. But I do believe after 5,000 miles it has become "broken in". I would double check that though. Rebuilds need time to be broken in before high RPMs are "healthy".

Rotary engines love high RPMs. At least, they love it more than piston engines.

I have bounced off 7800 before by mistake, my GXL just broke 200,000 kilometers on the odometer the other day. It runs and revs just fine, compression is strong. I never rev above 7000 (although a few times I have intentionally shifted at 7400), but that's just my driving style. If the motor isn't up to operating temperature, I try to shift at 2500 to 3000 RPMs. I do my best to give it alot of time to warmup before I start driving. As for regular driving when at temp, I shift at usually at 4500 to 5000 RPMs.

Make sure (if your rebuild is broken in) that you hit the high revs once or twice after it has reached operating temp. It will help prevent alot of carbon buildup, and overall keeps everything inside happy.

SleeperZzZ

I shift when the buzzer goes off... at about 8000-8100... but thats a s5

Black13B

iTrader: (1)

To clarify for anyone who isn't sure, S4s (86-88) have heavier rotors among other components that don't allow safe revving as high as an S5 (89-91).

Out of curiosity: When does your shift buzzer go off guys? Mine starts going off at 6250-6500.

Mr. Eccentric

S5 buzzer goes off at 8000.

For daily driving I shift at about 4000, any lower than that and you get bogged down when you take up the next gear.

TakumiJr

With my S4 i shift at 3K for safe driving. For racing i shift at 6900RPM. I think the buzzer go off at 6600RPM.

SleeperZzZ

So in s4's the buzzer goes of a little be4 redline, and in a s5 the buzzer goes of AT redline??? Ive seen my car go past 8grand a few times... i didnt mean for it to... but theres no reason to go that high... theres just no power there

brandon's rx-7

thx guys. so most of u guys are saying at around 5,500rpm is where u get the most out of it when your racing, and for daliy driving at aroumd 4k.

DC350

mines goes off at 6800 (s4)

brandon's rx-7

what gears do u guys rev it up till the rev limiter goes of. can u do it in all the gears from 1st to 5th.

TakumiJr

We dont have Rev limter on our cars. I wouldn't recommend goin past 7K on our S4 cars. Been stated already that the S4 rotor is heavier and don't allowed safe revving like the S5.

AE_Racer

iTrader: (1)

you shouldnt take an S4 car over 7k rpm, period.

Black13B

iTrader: (1)

Over 7K? Why not?

Sure there's no power up there, but why not over 7K?

When I posted the figures about the S4s vs S5s, I was talking about an S4 cannot safely reach 8K+ the way an S5 can, not 7K.

Just curious as to hear factual argument about why over 7K on an S4 is such a no-no.

JGard18

whoa, my mechanic used to take my 88 GXL up to 8,500 regularly on drives... ummm...thank god I don't have that one anymore (nor do I go to him anymore)

But yeah, regular driving, I shift anywhere from 3-5k. I haven't really raced my car, but when I start autocrossing it next year, I'll be shifting when I hear a buzzing.

AE_Racer

iTrader: (1)

everything in there is too heavy to be turning those RPMs...and there's no need to, like you said, no power, at all...

silverrotor

iTrader: (1)

My rev limiter has been disabled. Even still, my Crane Cams HI-6 Is adjusted to 7g for safe keeping. I switch gears at 4-5g but when It's time to get down, 6g Is my usual peak power being made here. This Is for a s4.

Black13B

iTrader: (1)

BlackRx7

if your street ported like me you can shift at 2500 or 3000, and it doesn't bog plently of low end power, I can go up a 40 deg hill in 3rd gear at 20 mph

Ryde _Or_Die

Why is everyone getting scared of high RPMs? I can shift where I want to, 7k, 7500, and be just fine. I redlined my old NA or actually went past 7k many many many times. Every shift sometimes. No problems. Car has gone through 2 other owners that did worse than me and it just ran a 15.0; S4 NA by the way. Quit worrying so much guys. If you are shifting at 5k while racing, you are losing...plain and simple.

silverrotor

iTrader: (1)

*Edit* Actually, It'd 6500rpms Is my usual peak power being made, not 6g If we are being exact.

AE_Racer

iTrader: (1)

im sorry...i have no valid statement to backup my arguement...but with my 88 n/a, after 7k, its like hitting an aerodynamic barrier, and the power doesnt increase, it just levels off...may be just my car, because it seems to be losing compression, at ~150k miles...I also dont have much of an exhaust, either

rx7raca

i shift at 7.5 with a 1/4 bp, anyone that says theres no power that high is wrong. the rotary gets its power from high rpms.

like ruff ryder said above. your losing if you shift at 5. this isnt a v8. put the engine to the max like it was made to be...

yes the s4 has heavier rotors, but they didnt put the redline at 7 for no reason. look where the rev limiter is. 7.8k... maybe on stock ports there is no power but when its ported you gain alot more power in the high rpms. IMO

5 point whoa

I redline when i'm running it, and when I'm just cruising i shift at 3-5

Ryde _Or_Die

Ya when you are just crusing you can shift whenever you feel like, I shift at 3k to save gas myself. But when racing you aren't using your power by shifting at 5k.