Nick7

Ok, I've read that some people blew up their engine by hitting rev limiter.
Can anyone explain why that happens?
AFAIK, when u hit rev limiter it should cut off fuel.. right? So, if there is no fuel - you aren't lean.. as there is *no* fuel to burn up (even though there is air..).
So, why does this blow up yr engine?

Rtype16

I am not sure about blowing up the engine rather than damaging some valvetrain in the head. Some engines just aren't built to rev that high. The other way is if they misshift or downshift and the RPM's go too high it doesn't matter if you are cutting fuel or timing it mechanically can't slow it down fast enough.

Mase

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Nick7 &raquo;</TD></TR><TR><TD CLASS="quote">Ok, I've read that some people blew up their engine by hitting rev limiter.
Can anyone explain why that happens?
AFAIK, when u hit rev limiter it should cut off fuel.. right? So, if there is no fuel - you aren't lean.. as there is *no* fuel to burn up (even though there is air..).
So, why does this blow up yr engine?
</TD></TR></TABLE>


People ARE NOT blowing up their motors by hitting the rev limiter. lets get that straight.

Evil DOHC

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mase &raquo;</TD></TR><TR><TD CLASS="quote">


People ARE NOT blowing up their motors by hitting the rev limiter. lets get that straight. </TD></TR></TABLE>

DITTO

TravSi

People blow the motors by thinking they can rev to 10500 rpms cause someone on honda-tech said so!

rev limit = good

USDM 4G VTEC

manyyyyyyyy turbo cars at the track bounce off the rev limiter for the first 60 foot

and they can handle it

lazerus

you blow motors up by not having a rev limit.

racinskittle

I cranked the fuel up past redline (till 8000 RPM) so incase i mis shift, i got fuel. Can't bank on the head stayin in one piece though.

dgonzals

if you are on the revlimiter constantly....you are bound to blow up....you can do it every once in a while...

brickonwheels

Can't you do damage by hitting the rev limiter with nitrous?

B18bEK

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mase &raquo;</TD></TR><TR><TD CLASS="quote">


People ARE NOT blowing up their motors by hitting the rev limiter. lets get that straight. </TD></TR></TABLE>
i'd have to agree with Mase ... i think i hit mine at least twice a day

Bulldogg83

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B18bEK &raquo;</TD></TR><TR><TD CLASS="quote">
i'd have to agree with Mase ... i think i hit mine at least twice a day </TD></TR></TABLE>

tick tick tick tick.........

Jockobo

everytime i smash into the rev limiter after missing gear i lose some compression...im talking about really smashing into it really hard for like a second or so...

1fstevo

If you mechnically over rev pass the rev limitor aka mis downshifting to the wrong lower gear, then you motor will go quick.

Muckman

iTrader: (2)

Id like to see what would happen if you downshifted to a rpm beyond the fuel map but within the capabilties of the motor.

Nick7

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mase &raquo;</TD></TR><TR><TD CLASS="quote">
People ARE NOT blowing up their motors by hitting the rev limiter. lets get that straight. </TD></TR></TABLE>

Well, that *did* sound dumb to me.. but some people claimed they blew up engine when they hit rev limit.
Also, MSD claims with their ignitions, it's better to cut out ignition instead of fuel as rev limit.
This all does sound stupid to me (why would fuel cut blow things up???), but wanted to hear also from other people

RedTegLS

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Nick7 &raquo;</TD></TR><TR><TD CLASS="quote">AFAIK, when u hit rev limiter it should cut off fuel.. right? So, if there is no fuel - you aren't lean.. as there is *no* fuel to burn up (even though there is air..).
So, why does this blow up yr engine?
</TD></TR></TABLE>
Am I reading that wrong or did he say there is no fuel so you aren't lean. If you have no fuel then you are lean! Bottom line is if you held your throttle wide open smacking off the revlimiter for an extended time you will damage your engine.

raene

Stock maps go to something like 9k and use the 9k rpm points for ignition + fuel beyond the highest point. So at 10k it will still be on 9k ignition/fuel, at 10k it will still be on 9k ignition/fuel, etc.

But if you're past the rev limiter your fuel input is zero anyway, so it doesn't matter.

Running lean is bad because it heats stuff up tremendously AFAIK. That leads to hot spots, which leads to preignition, which leads to detonation. But having no fuel means there is NO burn. You can't "run lean" on no fuel. You can't RUN at all on no fuel.

Johnyquest

I smash my rev limiter two or three times every time I drive. I got my d16z6 (stock) over 8k a few times by missing shifts and I often smash the limiter trying to ride out second and third... My motor has lasted 20k mi turbo already, so I'm not to worried.

trbob16a

I can't find my rev limit, its too high. I have it set at 9200 in hondata, the head is set up to shift in the 9k-9500 range, but the engine is just SCREAMING by 8700 so I normally shift before the limit. I only hit it once when running a ferrari because the tires broke loose up high in 3rd gear and I stayed on it anyway.

turbogeekDA6

yes the factory rev limiter and nitrous are enemies... this is why people "tear motors up bouncing off the rev limiter." the factory rev limiter cuts fuel. good rev limiters cut ignition. this is bc when fuel is the engine goes very lean... we all know what happens to nitrous motors that dont have sufficient fuel. if you have a dry kit its even worse bc then you are still dumping tons of nitrous into the motor with NO fuel. its a no brainer: get rid of the factory rev limiter if you are spraying. period.

acy76

The argument I've heard against the fuel-cut rev limiter in a FI application is that the fuel cut can come on regardless of the injector cycle - you could hit the limit right in the middle of an open injector, which would lean the mixture and greatly increase chances of detonation. This is just what I've read, someone with more knowledge of Honda ECUs etc. would have to confirm.

Mase

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by acy76 &raquo;</TD></TR><TR><TD CLASS="quote">The argument I've heard against the fuel-cut rev limiter in a FI application is that the fuel cut can come on regardless of the injector cycle - you could hit the limit right in the middle of an open injector, which would lean the mixture and greatly increase chances of detonation. This is just what I've read, someone with more knowledge of Honda ECUs etc. would have to confirm.</TD></TR></TABLE>

you people arent realizing there are like 50 cycles per second.

fsp31

My car is built for autox (going strong for nearly 6 years), and it's turbo'd (1.5 years). Autox cars tend to spend A LOT of time on the rev limit and mine is no exception. Absolutely no problems so far...

ZoRG

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mase &raquo;</TD></TR><TR><TD CLASS="quote">

you people arent realizing there are like 50 cycles per second. </TD></TR></TABLE>

Is that all, at 9000rpm theres 180 revolutions per second.