rev limiter

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The Bishop
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rev limiter

Post by The Bishop »

not sure if this should be mechanical or electrical but...

If whilst staionery I rev the nuts off my van it misses and splutters at high revs. I've been considering what the fault is. I've now come to the conclusion it might not be a fault. I have one of these fitted :
http://www.megabug.co.uk/rotor-arm-rev- ... -636-p.asp

Is it in fact doing what it is meant to do at 5400 revs?

Thanks,
1986 1.9 Petrol/LPG with Devon pop up.

billy739
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Re: rev limiter

Post by billy739 »

yes correct.

stops the rods flying through the air when you floor the pedal whilst stationary

for what ever reason you want to do that.

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Re: rev limiter

Post by DuaneEddy »

- one careful owner
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Re: rev limiter

Post by ghost123uk »

The Bishop wrote:
If whilst stationary I rev the nuts off my van it misses and splutters at high revs...

... at 5400 revs?




This is very much not a good idea imho, revving an engine like ours to that rpm with no load is not recommended

It's a good job you do have a rev limited rotor arm fitted
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CovKid
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Re: rev limiter

Post by CovKid »

I was going to post then decided it was probably pointless.
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sarran1955
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Re: rev limiter

Post by sarran1955 »

Hello,

Do you mean like this:

http://www.youtube.com/watch?v=ffO--SrYIE4

Cordialement,

Image

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Re: rev limiter

Post by ghost123uk »

They used to do that every year at one of the VW shows in the Midlands, forget which one.

Always thought it was a waste
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The Bishop
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Re: rev limiter

Post by The Bishop »

Thanks for the feedback.

Just to assure you - I was not trying to wreck my engine & do not make a habit of this. I was trying to identify anyother problem and when I reved it up noticed the missing.

The great news is that it's doing what it's meant to do so I don't have to worry about it (or do it anymore!).

Thanks for your help.

R
1986 1.9 Petrol/LPG with Devon pop up.

California Dreamin
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Re: rev limiter

Post by California Dreamin »

One revolution of the crankshaft equals 2 strokes of the piston.
5400 RPM = 5400 revolutions of the crankshaft PER MINUTE

Divide the 5400 by 60 (to get revolutions per second) equals 90 revolutions of the crankshaft PER SECOND.

Times that by TWO (two strokes of the piston per revolution) equals 180

That means each piston travels up and down the cylinder bores 180 times PER SECOND


Makes the mind boggle.

I wonder how fast you thought it: SUCKED/SQUEEZED/BANGED & BLEW.

Martin
Last edited by California Dreamin on 06 Jan 2013, 17:46, edited 1 time in total.
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Re: rev limiter

Post by billy739 »

keep going , ...

whats that in mph? whats the stroke?

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Re: rev limiter

Post by CovKid »

Regardless of the figures, these are 'chugger' engines, designed to work all day every day - testament to their longevity. I run with a stock Beetle rotor arm as I don't like to find myself floundering during overtaking but I'm still mindful of the limitations of a stock motor. For anyone unfamiliar with the limitations, the rev limiter rotor is a must.
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California Dreamin
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Re: rev limiter

Post by California Dreamin »

With a full camper conversion ie: padded engine lid, 5 inches of matress, carpets, blankets, chairs, thermo screen etc etc all piled up over the engine compartment, a 12 foot distance from the back to front, it is very difficult to hear the engine tone/revs especially on a wasserboxer.
This is the real reason for the rev limiter.

Martin
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Re: rev limiter

Post by ghost123uk »

billy739 wrote: keep going , ...
whats that in mph?
whats the stroke?

Aye, we discussed that once on a model aeroplane forum. Some of our racing engines rev at up to 32,000 rpm and we were wondering if the piston breaks the sound barrier. It didn't. The actual result was a surprise though. I won't spoil it by stating what it was.

Does anyone want to have a guess as to what average speed a WBX piston is moving at when doing 5,400 RPM then
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Re: rev limiter

Post by California Dreamin »

180 X 68.9mm (DG) = 12402mm a second (12.4 m/sec) 27.7 mph approx.....doesn't sound right?



Martin
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Re: rev limiter

Post by ghost123uk »

California Dreamin wrote:180 X 68.9mm (DG) = 12402mm a second (12.4 m/sec) 27.7 mph approx.....doesn't sound right?
Martin

That's what I meant when I said the figure might be a surprise The tiny piston in the 2.5cc 32,000 rpm racing model aeroplane engine was 16mph iirc. And we wondered if it was breaking the sound barrier
Got a new van, but it's a 165bhp T4 [shock horror] Accurate LPG Station map here

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