Redline/Rev Limit

In my car, the redline is 6500, however, I can take it clear to 6900 and sometimes 7000 I think, it happens kinda fast and I might be mistaken. But why is the redline there if you can push it past there? Why is there the difference between the redline and fuel cutoff?

who knows all i care about is that i can take my si to 7200 baby :biggrin:

Redline is where your car should be shifted if you're racing. Optimum point for most power.. Your car is likley making less power when you're running it past redline.

Fuel cutoff is becuase people aren't smart enought to shift at red, so it has to have a rev limiter so people don't float valves.

and yes i did know that you are not supposed to take it as far as it can because at a certain point you are actually putting out less power by taking it too far, so no im not a dumb ass

Originally posted by XxLuckyLisaxX
so no im not a dumb ass

DE - FENCE!

No one was calling you a dumbass.. I'm saying that by taking it that far the reason it cuts is to save your motor. Answering the original question. :bloated:

first off the rev limit on a PM5 ECU is 6800, on a PM6 it is 7200 and on a PG7 it is 7500.

secondly, in response to shifting at redline for maximum power.... unless you have a VERY close ratio transmission, shifting at a higher rpm, although making less power at the time, would actually be faster becuase you are still making power, just less than peak, and the higher you rev, the higher rpm you will drop back in at after shifting.

Its better to rev higher and make a little less power than at peak, and then drop rigth back into the powerband at your peak torque point than it is to shift at peak power and drop below your peak torque.

On a b16a b17 b18c b18c5 , if you build it right it will make power up until about 9500 RPM. :bigthumb:

My B18b was built up to make power up unitl 7500. Peak at about 7200.

And if your woried about floating valves, Try Skunk2 or Crower.

my zc has a pm7 ecu which hasnt been chipped and the limiter comes in at 7200..... although on some occasions when puttin car thru its paces the limiter wont come in til 8000rpm i shit u not! strange....

I CAN TAKE MINE TO 8000!! THE FULL RPM!!..oh yea, my ecu is chipped :tongue: :dogpile: :tongue: :tongue:

my friend has a fully built b16a3 in his 97 EX.
Revs it to 11.5
TODA Internals. WHOOHOOO:worshippy

Dyno'd at 215 hp to the wheels

[QUOTE]Originally posted by 91civicDXdude
[B]first off the rev limit on a PM5 ECU is 6800, on a PM6 it is 7200 and on a PG7 it is 7500.

I know that this has probably been asked before, and I can slightly remember the post for it. However, what ecu is my 91 lx? I cant remember where to find it for the life of me, but I want to know for future reference.

Originally posted by JDM 4g4D
my friend has a fully built b16a3 in his 97 EX.
Revs it to 11.5
TODA Internals.
Dyno'd at 215 hp to the wheels


11,500rpm on Todas, making 215whp?!
Not buying it without dynos. Sorry buddy.

http://www.honda-tech.com/zerothread?id=178191

ok now could one of you explain exactly what hapens when the cecu cuts the fuel well i know it cuts the fuel but what hapens next? does the car die on you does it go down to the lowest rpm ??/


most of the time when i'm really going to the max right
a get to a point were the pedul is like not responding anymore and like it's not getting any gaz
but i'm never at that high an RPM why does that hapen ? what could be cauzing it ?

once i was racing this other civic and almost crashed in the behiND of this big pick up but after braking down the car did 'nt want to acelerate

Ive never actually done it driving, but I would imagine its basically the same as when youre just revin when sittin there. It will hit the fuel cutoff point and stop and then re-engage and hop back up to the cut off point. It should just hop up and back down over and over as long as you keep gas to it. I could be wrong, anyone else know for sure?

It will hit the fuel cutoff point and stop and then re-engage and hop back up to the cut off point. It should just hop up and back down over and over as long as you keep gas to it. I could be wrong, anyone else know for sure?

:bigthumb:

Now on my EX i believe I have the pm6 ecu and after the cars warm i can go up to 7500, 300rpm past what the rev limiter says it cuts off at...why is this?

Because youre car is stupid. J/k Mike, I dont know, is this with your zc or with your old engine?

lol yes i am just the stupid one. This was on my old d16a6...i haven't gone up that high yet since havin my ZC, only had it since sunday and wanna be careful at the beginning, lol.

Good call, I gave mine like 300 miles on it before I let it above 4000 rpm. I was really scared of it goin tits up.

Yeah i have like 350 on it so far in my car and the highest ive taken it is 5,000rpm and all that.

Originally posted by Black91si
I CAN TAKE MINE TO 8000!! THE FULL RPM!!..oh yea, my ecu is chipped :tongue: :dogpile: :tongue: :tongue:

Carefactor=zero :loser:

Stock ECU and mine does that straight from the factory:bigthumb:

Originally posted by JDM 4g4D
my friend has a fully built b16a3 in his 97 EX.
Revs it to 11.5
TODA Internals. WHOOHOOO:worshippy

Dyno'd at 215 hp to the wheels

I was just thinking how nice it was that people wern't bullshitting on the forums anymore :rolleyes:

The Si versions come with PM6. LX, DX, etc. comes with PM5.
Flunky
PS-Only way you're going to go over 115MPH is down a big-ass hill with the car loaded down. Get some fat friends!

Now on my EX i believe I have the pm6 ecu and after the cars warm i can go up to 7500, 300rpm past what the rev limiter says it cuts off at...why is this?

your tach is off.

Not necessarily, redline on the SiR is 8000 according to the tach, yet the cutout kicks in at 8200. Safety margin I guess