Abusing your car?!?

hey. a few people were talking (in earlier posts) about drivers abusing
their VTEC engines. Is this actually possible, i assume they mean they rev
em hard, but the VTEC doesnt kick in till 5,000-5,500 revs (is that right?)
so surley the engine is made to rev high? obviously not all the time, but it
cant damage the engine to rev it to 6 grand say?
i dont know a lot about engines which is why im asking, so dont burn me
please!

cheers

 

8 grand say!

And they love it.

Which is why we love them!

 

As long as you shift before redline, it's OK.

 

So why do people talk about abusing their engines on a VTEC???

 

Probably because they grew up with Detroit iron that floats it's
valves at 5000 RPM. The howl of a high revving engine makes them
nervous.

 

The DX/LX motor can handle the high rpm. Hopefully the more high-strung, higher
rpm, vtec version can do the same.

Pars
98 DX Hatch

 

Took the words right out of my mouth. And very right. People who cringe at
revving an import are usually used to domestic cars that don't rev as high
and have very different power curves. There's absolutely nothing wrong with
revving a Honda up to redline. Some people seem to think that taking a car
"near" redline is abuse. If such RPMs were dangerous, then the car would
have a lower redline limit. It's called redline for a reason.

 

I wouldn't worry that much even if you didn't. I've hit the fuel
cutoff (8K?) a few times, but not for a while. The fuel is cut
off for a split second - just enough to keep the engine from
running at redline for more than that split second.

 

No problems here after 140K miles of spirited driving.

It's only abuse if you're revving without reason, cruising in low gear
all the way to work. Zipping up a steep mountain or accelerating hard
up a short onramp is normal use of the engine. I've even held my Civic
within 400 RPM of redline up the hill from Bishop, CA up to South Lake
in the Seirras. (Ow! Ears pop!) Worth the photos:

http://www.pixelmemory.us/Photos/SF%20Bay%20Photo/Oct%2012%202002/

 

Just change the oil regularly and stay away from nitrous.

As part of engine development, manufacturers routinely run engines at
very high, sustained rpm for many hundreds of hours.

JM

 

I'd also suggest letting the engine and oil warm up (with easy driving)
before approaching redline. After that, it's just called "getting the
hp you paid for."

 

I'm not an engineer, nor a very competent car mechanic. But my recollection
is that it has - at least in part - to do with the actual speed at which the
piston is travelling. In oversquare (or nearly so) engines, the stroke is
not much longer than the bore. In such an engine the piston does not travel
far before it reaches the top of it's stroke. In doing so, the maximum
velocity of the piston is lower than in a longer stroke, where at the same
rpm, the piston must travel a longer physical distance in the same amount of
time. Higher speed incurs oil distribution problems, temperature, friction,
acceleration/deccel, etc. I.e. the short stroke high rpm engine is actually
less 'stressed' than the long stroke low rpm engine.

'least that's how I understood it... any experts out there?

Once had a 2-stroke formula racebike. Didn't even get going till around
10k. Great fun!
a

 

Your asessment is correct as far as it goes, but there are other
factors. There have been improvements in the alloys of which engines
are made these days. Also in smaller engines, the components weigh
less so the inertial forces aren't as great. Dual overhead cams and 4
small valves per cylinder instead of two big valves means lighter
components and lower inertial forces also. The valve springs don't
need to be so fierce to prevent float.

And modern F1 engines are turning 18,000 RPM.
That's 18000/60 = 300 up and down strokes per second, and that
means a piston speed that is scary! Of course they only have to keep
it up for 200 miles...

 

19.5k for last years BMW's.

We'll see about this year with the "one engine" rule.

 

Dang, haven't those rule changes made for some interesting races?
That run-with-the-fuel-load-you-qualified-with rule sure made things
less monotonous.

 

My bike had one veeery thiiin piston ring (reminds me of monty python puke
skit). Was supposed to be replaced every 50mi or so - i.e. after each
morning on the track. Yikes!

 

I'm not sure if "abuse" is the right word, but folks who operate their
engine regularly in the high-end of the RPM range, will require additional
maintenance, and will lose out on long term longevity.

However, aside from that, VTEC engine are designed to run at higher RPMs,
and will regularly do so just fine.

 

Bad maintenance habit will have a greater effect on the car's longevity when
compared to high revving 'abuse'.

Pars