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[shyboy]

I've read many comments about 2.5l/ 2.6l V6 ECU's limiting RPM to 4k/4.5k when certain things go wrong. If I ever reached 4k rpm in 5th. on my manual box wouldn't I be close to 90mph. Am I missing something here? The rpm figure does refer to crankshaft revs., doesn't it?
Also, I've read that the rear multi ram on V6's comes in at around 4k rpm. and that it can be visually checked. I would be very timid about revving the engine at that speed in a stationary car for anything other than a few seconds at the most. From what I can make out, most of my driving, (and I'm not a total slouch), takes place between 2.5 & 3.5k rpm.
Am I totally under-estimating the ruggedness of these engines, and are they really designed to go close to the top end regularly without over-stressing them?
I try to visualise the pistons moving up and down in the bores at such speeds and wonder why everything doesn't just blow apart!
My father (he's 96 and fitter than I am), was an engine fitter in the RAF during WW2 and the principals of internal combustion were taught and practised to a level which modern day mechanics couldn't start to understand. If an aircraft engine was pushed to a very high level, 'through the gate', for longer than a very short period, it had to be completely dismantled and rebuilt. I know the standard of technology was quite different from today, but I still wonder whether some of the problems we have are related to engine 'punishment'.
Am I talking rubbish?  I'd love to read the views of the experts.

[JamesV6CDX]

I regularly drive my V6 manual up to the red line at 7+k Rpm

They can definately take it, have you seen how they drive them on Road wars?

[shyboy]

What speed does that give you James? And can it really take it without protesting?
Haven't seen Road Wars, but I presume that's not the way most of us drive. ??Is it???

[TheBoy]

My v6 frequently spends lots of time in the 4.5 - 6.5k rpm range . Until it needs a drink that is

[JamesV6CDX]

Haven't seen Road Wars, but I presume that's not the way most of us drive. ??Is it???

 

I never drive dangerously, or close to anything etc... but I love to push my car / engine  

My RPM also spends most of it's time over the 5k mark....

[JamesV6CDX]

Although it's a V6, the Omega is also not far from a 2 tonne car, so I find it HAS to be pushed up to the red line if you want decent performance....

[Bandit127]

An "Italian Tune Up" I think?

The red line is there for a reason and it's negligent not to use it.. now and then.


Jim

[shyboy]

OK! If you won't tell me what speeds these rpm entail, I'm just going to have to go out and test it myself.
Spare underpants in the glove compartment!  
Hope to speak to you again. Maybe.

[Marks DTM Calib]

Aircraft engines and modern car engiens realy air light years apart.

The V6 has a lot of low down grunt and a nice flat torque delivery and hence why they pull well in the low gears and hance also why the ides of soembody putting a close ratio 6 speeder in would be pointless (only requried on peeky engines like modern over blown diesels).

This is all thanks to the multiram.

But it does them good to rev occasionaly as it does any multivalve engines and 8k is not that high, bike engines can rev to 15K (although they dont last much more than 10K miles without work) and some car engines to 9K (eg Honda S2000).

The V6 uses slipper pistons, a well balanced crank, good rods and even has a main bearing girdle for stability....which is hugely different to the engines of old where the piston on its own weighed many pounds and the the stroke was very long (V6 is a square engine by the way stroke is approx equal to the bore)
.

[Kevin Wood]

Aircraft engines are also designed to run at or very close to their rated power for hours on end. Run an aircraft engine at less than 70 or 80% power and you'll land!

The upshot is that aero engines are huge capacity, low revving devices with big, heavy internals in order to generate high power at low RPM and they can't take high revs. (most are also barely post-war in their design) As Mark said, a long way away from the engine in your Omega.

Give it a run to the red line every so often. It'll love it. So will you

Kevin

[Bandit127]

Aircraft engines are also designed to run at or very close to their rated power for hours on end. Run an aircraft engine at less than 70 or 80% power and you'll land!

The upshot is that aero engines are huge capacity, low revving devices with big, heavy internals in order to generate high power at low RPM and they can't take high revs. (most are also barely post-war in their design) As Mark said, a long way away from the engine in your Omega.

Give it a run to the red line every so often. It'll love it. So will you

Kevin

The way aircraft engines manage to run at rated power for hours on end (reliably) is by being conservatively tuned. If you want the same power as a 2.6 you need over 6.0l of aircraft CC!
http://en.wikipedia.org/wiki/Lycoming_O-360

[Kevin Wood]

Was looking at one of them on a bench a few weeks back. Just a (heavily) pregnant beetle engine.

Kevin

[The Barge Captain]

Other than it's the front multiram that opens at 4K, and you only have to blip it off load to get it to open, go on---Give it some.
She will really take off and start to fly(assuming your vacuum system is intact).
My Missus complained of whiplash in my 2.5 the other week

[Markjay]

4.5... 6... 7k RPM??? OMG! I never go over 2.5...

[Bandit127]

4.5... 6... 7k RPM??? OMG! I never go over 2.5...

LOL. You are performing a sterling service to the forum group here. Storing all that carbon in your heads, thus allowing us to "offset" our occasional full bore blasts.

We are eternally grateful.

Jim