Overrevving?

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Mouse
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Overrevving?

Post by Mouse »

What's the consensus for over revving a diesel engine?

It would be nice to be able to get a few extra mph and bring top speed up to 65mph but that would mean revving to 3750rpm, an extra 150rpm.

I cant see the harm for such a small increase but would like to mention it in case I'm making myself a whole world of hurt.
Last edited by Mouse on Fri Apr 02, 2010 8:55 am, edited 1 time in total.
Kubota Z482 which is plodding on with unnerving reliability. Three years so far.
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cumorglas
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Re: Overrevving?

Post by cumorglas »

mouse,

I LOVED your build. but i want you to know that those of us with 3600 rpm diesels hate you right now.
Mouse
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Re: Overrevving?

Post by Mouse »

That would be the god of the typo at work!
Kubota Z482 which is plodding on with unnerving reliability. Three years so far.
1900 Diesel Bike being rebuilt with better clutch control.
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andrewaust
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Re: Overrevving?

Post by andrewaust »

I've had the Yanclone to 4200rpm, valve train is one of the weakest links/Big end one of the others, harder springs could be replaced to stop the valve face hitting the piston. Indirect injected diesels of some variants can be rated up to 5000rpm, Direct injected diesels tend to taper off around 4000rpm but watching the tractor pulls they are revving the engine to 6000 - 7000 rpm http://www.enginebuildermag.com/Article ... arket.aspx

So with good volumetric efficiency (blower/turbo) high rpms could be achieved but at a price :) My comfort zone is no more the 4000rpm. ;)

With more rpm/more power the life of the engine reduces considerably.



A ;)
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coachgeo
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Re: Overrevving?

Post by coachgeo »

Mouse wrote:That would be the god of the typo at work!
feel free to edit your post to fix your typo. You might get more answers.
Mouse
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Re: Overrevving?

Post by Mouse »

Done.
Kubota Z482 which is plodding on with unnerving reliability. Three years so far.
1900 Diesel Bike being rebuilt with better clutch control.
Mouse
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Post by Mouse »

That was a waste of time. The engine wont produce enough power to go faster than 60 unless its down hill then the most I saw was 62mph which is hardly worth the effort.
Kubota Z482 which is plodding on with unnerving reliability. Three years so far.
1900 Diesel Bike being rebuilt with better clutch control.
Anorak_ian
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Re: Overrevving?

Post by Anorak_ian »

If your engine is low compression, and glow plugs may indicate that this could be the case, then a turbo may well be suited to it.
I guess over rev it a bit, but not to often.

If you want more top end then you need to play with the gear ratios, a tall top gear will get a few more mph.
You can get different ratios for beemer boxes.
IgorVigor
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Re: Overrevving?

Post by IgorVigor »

Depending on how much smoke its already producing of course, you could increase the amount of fuel from the pump...

It can make a difference to oomph...

Apart from that increase the compression a little...
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