Like the title says, is there any way to get rid of the rev limiter? thanks!

Eric

I would also like to know...but without another ECU, piggyback or something expensive please.

Stefan

Well, those were your two options. New ECU or piggyback chip is the only way to do it. There really is no need however- the powerband drops off sharply before the ECU cut, and only gets worse thereafter. You RS-T folks are a different story, but if you are NA, there is no point.


Brian
http://www.ravensblade-impreza.com
http://www.imprezamods.com
http://www.scoobymods.com
...something that rhymes with bones

Na, no point? usually NA need more revs to make the power... Even intake and exhaust make it worthwhile to explore a 7k limit. If you add cams, a 7k limit would deffinately be worthwhile.

Don't forget about upgrading the valvetrain with stronger springs, as I think the valves will start to float at about 7500 RPM. But without new cams and valvesprings, the extra revs aren't going to do much for you.

well, considering I have a EJ22T with a Turbo and Nitrous I think i can up the limit just a little :) :) A friend of mine has the same setup (well, a little better) and goes 7,600 :)

Eric

Originally posted by Imprezinator
well, considering I have a EJ22T with a Turbo and Nitrous I think i can up the limit just a little :) :) A friend of mine has the same setup (well, a little better) and goes 7,600 :)

Eric

Eric, are you sure about this? I still thought that a turbo'd EJ22 or EJ25 still has the same powerband as it does when it's stock. Same for nitrous! What I mean is that power is made and dropped at the same points as it does when it is stock, just with more hp involved. That being said, upping the rev limit would still yield the same results as it did when the car was stock. Yeah, my logic maybe thrown off a bit but do you see my point? I'm basing my turbo'd vs N/A powerband thoughts on dynos that I've seen on this site with 2.5RST's.

His Car supposedly ( I haven;t ridden in it) pulls just as hard all the way up to 7,500rpm's. He is an i-club member that I definetly trust.

Eric

And yes, the Valve springs are definetly goign ot be aftermarket

Eric

Cams will make a huge differance at the end of the power band. I have the Cobb cams and the car will bounce right off the rev limiter with no power loss. It wants to go past and is still pulling. With valve springs and such the cams would definately make going to 7000 RPM's worth while.

Tim

So there is nothing I can do without getting some sort of piggyback or something? bummer.

Eric

exactly what rpm does the 2.5 loose power??

Originally posted by flent
exactly what rpm does the 2.5 loose power??

When the needle drops and the smoke pours.

I had an idea awhile back to make a simple electrical circuit (simple in theory... at least) that would go between the engine RPM sensor and the ECU and would do the following:

If car is going from 0-6000 RPM, the signal would be unmodified & ECU would see the proper RPM.

If the sensor says the car is going from 6000-7000 RPM, the signal sent to the ECU is the voltage for 6000 RPM. So, even though you are going faster, the ECU thinks you are still below the rev limiter.

When you hit 7000 RPM (or above) the voltage clamp "disappears" -- and the ECU will see the actual RPM minus 750 (so if we are going 7000 RPM, the ECU sees 6250 RPM, and the rev limiter kicks in).

Anyone know of anything that might keep this from working? Or is this potentially dangerous? The circuit is simple with only a few diodes, op-amps, and resistors.............

Dave

Seems like a descent idea but it would cause your tach to stop working above that rpm I believe

Eric

Wouldn't that circuit idea also cause the coilpacks to fire at 6000RPM despite the engine spinning faster than that? Or are the coilpacks on a seperate "dumber" circuit?

Aha... you're absolutely right. Scratch that idea... :)

Getting proper fuel is another problem, as the stock ECU has a blank fuel map for over 6250 rpm.

Let's put it this way, if you're going to spend the money to mod your car to were it would need to be beyond the rev limiter, than another few hundred won't be much of a cost for the ecu or piggyback.

-Matt

True :) I guess I should get a piggyback. hehe

Eric

Let's put it this way, if you're going to spend the money to mod your car to were it would need to be beyond the rev limiter, than another few hundred won't be much of a cost for the ecu or piggyback.

Good luck finding a ECU replacement for a few hundred. Vishnu wants 2K for the TEC-II, which is most widely used and well supported. Other aftermarket ECUs also cost over a thousand, plus getting it properly tuned...$$$$$

I guess I should've put plus or minus a few thousand, but my point still stands, if you're going to be putting in the thousands of dollars into your car to the point were you'll have a valid reason to remove your rev limit, then another one or two thousand won't be much...

-Matt

Buy my car. It doesn't have one. Could be screwed up I don't know. I've been over 7k once.

Originally posted by nomorefocus
Buy my car. It doesn't have one. Could be screwed up I don't know. I've been over 7k once.

Your tach could be out of calibration at high rpms. Shiv has found wide discrepancies with the stock tachs and what he reads from TEC-II. Try staying on the gas longer, it will eventually cut out.

-WaC
Wayne

It's funny this conversation always comes up, I was just reading the mike shields faq. He even suggests lowereing the redline if you go turbo... but then again the faq is quite out of date.
AO

Originally posted by wac


Your tach could be out of calibration at high rpms. Shiv has found wide discrepancies with the stock tachs and what he reads from TEC-II. Try staying on the gas longer, it will eventually cut out.

-WaC
Wayne

I was thinking that too. It's just kind of scary to get that high in the red though...
Anybody know what my tach should read when I'm going a constant 70mph?

70 in what gear?

-Matt

Originally posted by jhonas
70 in what gear?

-Matt

How about more than one gear, since it could just be at higher RPM's. Like 3rd and 5th...

5th: 3125rpm's (or really close to that).
4th: 4500rpm's (or really close to that).
3rd: Didn't know if my downshift to 3rd at 70 would red line or not, so didn't try.

-Matt

Originally posted by m750
It's funny this conversation always comes up, I was just reading the mike shields faq. He even suggests lowereing the redline if you go turbo... but then again the faq is quite out of date.
AO

That and we're just buying 'presents' for our cars... I've read a few drag race times with cars with just 'presents' who run low to medium 14's ;)

Korey

k-dawg true, true

how else am I to get on my car's good side... buy it presents.
AO

Originally posted by jhonas
5th: 3125rpm's (or really close to that).
4th: 4500rpm's (or really close to that).
3rd: Didn't know if my downshift to 3rd at 70 would red line or not, so didn't try.

-Matt

hmmm that's what I got too. 3rd was 5800rpm btw.

I hit 70 in 3rd at 6000 rpms on my tach.