Changing Rev limit on 4AGE blue top.

[Stealer Of Souls]

Is there an easy way to adjust the rev limiter. At this stage I don't wanna remove it, but I would like to move it out by about 500 rpm.
My rev limiter seems to be at 7300rpm, which is a tad unusual because everything I find says it should be more like 7800.
Anyways. When I was on the dyno my curves were still strong at the rev limit, so I figure that I could possibly squeeze a bit more useful rpm/power out of the motor.

[no_8wire]

As far as I can remember therr is no rev limit bar valve bounce on all 16V 4ages

[Stealer Of Souls]

As far as I can remember therr is no rev limit

I understood this far...

bar valve bounce on all 16V 4ages

What is the rev limit bar valve bounce?

Or is this suppose to read...
AFAIR there is no rev limit, bar, valve bounce on all 16V 4ages...
If so, mine definitely cuts at around 7300.

[Dirtbag]

My mates redtop deff has a rev limiter, I have never been in an EFI car without one.

As far as I know there is no easy way to remove the limiter. Only way I have heard of is with aftermarket ECU

[IH8TEC]

My mates redtop deff has a rev limiter, I have never been in an EFI car without one.

agreed. no8wire, where did you come up with that unfactual statement

[KwS]

to my knowledge, all efi cars have a rev limit set in the ecu... its just one of those things that goes hand in hand. efi and rev limit.

My mates old redtop 16v 4age definately had a limiter... but i thought it was closer to 8k than 7k

[no_8wire]

mmm....I thought it was bounce at around 7800-8000 on the MR2...

Oh well I guess I could be wrong...

Doest the rev limiter keep it steady at the rev limit or does the revs bounce hit it? eg drop a hundred/then go back up

[Dirtbag]

up/down/up/down

different cars have different speeds of that up/down and amount of up/down

[jondee86]

Pretty certain 16 valves have a fuel cut to prevent over revving. Just
turns the injectors off until the revs drop a bit.... from memory cuts at
about 7600 or 7800 on a blue top. Not much point in going that high on
a stock engine, as you are way past peak torque, and you go faster by
grabbing another gear.... my 2 cents worth

Cheers.... jondee86

[l1ttle_d3vil]

mine valve bounces at around 7600rpm - 7800rpm, fairly sure there's no fuel cut or rev limiter on it. although my fuel pump is wired up separately to the ECU so no way the ecu can cut that, not sure on injectors though...depends if it cuts the earth signal or power to them.

[JRS]

i'm fairly sure you don't know the difference between rev limiter and valve bounce. even if your 4age DID have no limiter, ther's no way valve bounce would occur at 7600 rpm (unless the springs are really tired).

[Barks]

And it doesn't matter how or where your fuel pump is wired, it's the ECU not opening injectors. That's how fuel cut works.

Can someone find an old 3K or something and rev it to valve bounce, then post the video somewhere so people know what valve bounce is? Seems to be a few people have trouble distinguishing valve bounce and rev limiting.

[l1ttle_d3vil]

i'm fairly sure you don't know the difference between rev limiter and valve bounce. even if your 4age DID have no limiter, ther's no way valve bounce would occur at 7600 rpm (unless the springs are really tired).

I may be getting confused with the speed-limiter, as opposed to rev-limiter and valve bouncing but there is a difference in how they feel (in my experience). just had to go out in my car so decided to see exactly where it limited, it had a slight hesitation at about 6800rpm, then valve bounced/limited at 7000, then the revs crept up to around 7200rpm...

[CAMB01]

In my old 4age bigport, i had aftermarket cams and springs, and would hit the limiter at 7800rpm.
The springs were nearly 3 times the pressure than standard so there was no way of valve bounce.
It was rev limiter.

I have heard of some bluetops having quite a low rev limit around 6800rpm, i think they were the very very early ones.

[Caveman]

Do you have speed sensor going into ecu?

[neo]

Valve bounce is a lovely ticking which then turns into a wicked knocking noise (like a wood-pecker) , but this is my experience from a push rod engine =)

Valve bounce would not make the rev's rise and fall, it would simply flatline the revs.

[solitaire]

I only redlined my small port once... Im pretty sure it died at 8,500 and came back at 6.... But reading what you guys have said maybe it was 8.... it definitely sounded an assload more than 7,800

[SUBARUCONVERT]

me and a mate were killing a 2E yesterday, its carby, it valve bounced over 10k (off his 10k tach) so i cant see a 4age valve bouncing any less than 8.5k. I know my old bluetop limited around 7700-7750. A limiter is distinctive as the revs rise and fall. where when the valves start bouncing they just sit flat on what ever rpm. Im tired of people staying valve bouncing when its just the limiter

And on topic, are u sure ur tach is 100% accurate. my old FXGT one used to get stuck or move slowly. when id be doing 7k, it would show like 5.5k then suddenly shoot to 7k without the revs rising

[NA Drifter]

Here is a video clip of my 86 rev cut... especially in 3rd gear

http://www.youtube.com/watch?v=zCy99sZ3HPU

Sometimes it cut at 7200rpm, 7400rpm, sometimes 7800rpm still std ecu..

[Stealer Of Souls]

Do you have speed sensor going into ecu?

Nope. Still running the AE85 dash so no speed sensor output (or at least I don't think it's got one).

Sometimes it cut at 7200rpm, 7400rpm, sometimes 7800rpm still std ecu..

Do you mean the same ecu unit or different ecu units? I always thought mine went up to 7800 before cutting, but when I was on the dyno the sheet came back with a 7300ish cut. I thought it was weird, so worked out how fast it would've been going in that gear at that RPM and sure enough, 7300ish when it cut...

Does it have to do with temperatures and that? Perhaps cuts lower if engine cold????