MAD RPM.....Whats your cars limit !

dak

William Cosworth V8 getting to 20002 rpm !


http://videos.streetfire.net/video/156f6ec6-a8aa-4674-80b0-993e009f6283.htm

JHMEG

Some of the other F1 cars go to 23 or 24k.

Mine's quite a bit lower at 8,500rpm

colm_mcm

8,500 nothing to be ashamed of. Think the rev limiter cuts in on mine at 8000 or 8500. not that I'd ever be redlining it!:p

JHMEG

LIGHTNING wrote:

Its nothing to be ashamed of those F1 engines shred themselves after a few hundred km`s and you will laughing all the way too 200k

True I suppose. The last one had 221k kms on it when I sold it, and was going strong. It revved to 8,500 aswell.

C_Breeze

Well i've a 1.8 VTEC that redlines at 8500rpm and a V6 that redlines at 7000rpm. Give me a V6 over a VTEC anyday

JHMEG

C_Breeze wrote:

Well i've a 1.8 VTEC that redlines at 8500rpm and a V6 that redlines at 7000rpm. Give me a V6 over a VTEC anyday

Or how about a VTEC V6?:D

C_Breeze

JHMEG wrote:

Or how about a V6 VTEC?:D

Out of my price range unfotunately! New accord coupe.. mmmm

colm_mcm

meh! High revving V6's are old news.

afatbollix

i was in an accord that id say went to about 15000 rpm went from 5th to 2nd and she dident break!!!!!

JHMEG

colm_mcm wrote: »

meh! High revving V6's are old news.

Oldie but goldie.

I'll accept high revving V8s are now in vogue (Audi RS4 etc), with V10s on the way (some are here already). V6s may not be in fashion, but high revving is!

S.I.R

my pike revs to about 400 rpm ( manual power FTW ) also , cant them crappy 1.6 vtecs rev to 9500-10,000 when re-worked ?

C_Breeze

S.I.R wrote: »

my pike revs to about 400 rpm ( manual power FTW ) also , cant them crappy 1.6 vtecs rev to 9500-10,000 when re-worked ?

They can rev to whatever you like if you derestrict the rev limiter



..... for how long though , i dont know

colm_mcm

JHMEG wrote: »

V6s may not be in fashion, but high revving is!

Where does that leave my MIVEC V6 then ?!

JHMEG

colm_mcm wrote: »

Where does that leave my MIVEC V6 then ?!

Not fashionable:D But do you care about fashion? Are you a fashion victim?

BTW, nice engine that. And the 4-cyl 4G92. Nice the way the intake and exhaust third lobe can lock up independently, unlike VTEC. Nice the way Mitsubishi licensed the lock up mechanism from Honda too:D.

Rear bank spark plugs a ba$tard to change tho? One of the (only?) problems with transverse mounting a V6.

E92

Unfortunately anything with 6 cylinders is very much out of fashion it seems.

I can't understand why, a straight 6 is the most refined and smooth engine this side of a V12. Even V8s and V10s will not offer the smoothness of a straight 6.

Now, a V6 is a much sweeter engine than a 4 pot, but the real benefits of 6 cylinders are found only if you use a straight 6. BMW and Volvo are the only makes that still use a format that should be used by everyone else.

I know that straight 6s takes up more space than a V6 or even a V8, but Volvo can engineer straight 6's that are no larger than a rival's V6, so if they can do it, then why can't everybody else?

The quote below explains why a straight 6 is the best for smoothness this side of a V12

Wikipedia.org wrote:

Straight-6 four-stroke cycle engines are in perfect primary and secondary balance and require no balance shaft. They are in primary balance because the two ends of the engines are mirror images of each other and the cylinders move up and down in pairs, one on the compression stroke and the other on the exhaust stroke. Piston #1 balances #6, #2 balances #5, and #3 balances #4, canceling the end-to-end rocking motion that would otherwise result. (This does not apply to two-stroke cycle engines.) Secondary imbalance occurs in straight-4 engines because the two pistons on the upper 180 degrees of the crankshaft rotation move faster than the two pistons on the lower 180 degrees, creating an unequal motion. Straight-6 engines have cranks at 120 degrees to each other, so the differences in speed on different parts of the crankshaft rotation are offset by the changing number of pistons on each portion.
The straight-6 is also smoother than engines with a fewer number of cylinders because the power strokes of pistons overlap. Since each power stroke lasts 180 degrees of crankshaft rotation, while a new piston starts its power stroke every 120 degrees, there are 60 degrees of overlap on each stroke in which one piston is finishing while the next is starting. This results in a smooth delivery of power, unlike a four cylinder engine in which each piston must come to a complete stop before the next piston commences its power stroke. This makes the straight-6 engine's delivery of power much smoother than a four-cylinder engine. This is the reason why 60 degree and 180 degree V12 engines are considered optimal for smooth power delivery; they allow for complete overlap of the power stroke between three cylinders at all time due to interleaving the overlap from their two component straight-6 banks. Eight cylinder engines also have even more power stroke overlap than six cylinder ones, but the improvement in smoothness is not as pronounced.

Balance and smoothness

Due to the odd number of cylinders in each bank, V6 designs are inherently unbalanced and can benefit from some auxiliary counterbalancing. A V6 is basically two straight-3 engines running on the same crankshaft, and since the straight-3 suffers from a dynamic imbalance which causes an end-to-end rocking motion, the V6 also suffers from the same problem. Unlike the V8, the V6 cannot be laid out so that the vibrations from the two banks cancel each other or can be offset by counterweights on the crankshaft. This vibration is particularly bad in V6s derived from V8 engines with a 90 degree angle between cylinder banks. As a result, V6s can develop significant odd-order harmonic crankshaft vibrations, which can be counteracted by the use of a heavy duty harmonic damper to avoid possible crankshaft failure at higher engine speeds. These vibrations can be reduced significantly by using more sophisticated crankshaft designs, and can be eliminated completely by adding a balance shaft. Unlike a straight-4 engine, which requires two balance shafts rotating in opposite directions at twice crankshaft speed to cancel its vibrations, a V6 needs only one rotating at crankshaft speed, which can be nestled between the cylinder banks in an overhead camshaft design.
Six-cylinder designs are more suitable for larger displacement engines than straight-4s because the power strokes of pistons overlap. Since each power stroke lasts 180 degrees of crankshaft rotation, while a new piston starts its power stroke every 120 degrees, there are 60 degrees of overlap on each stroke in which one piston is finishing while the next is starting. This results in a smoother delivery of power than a four cylinder engine, in which each piston must come to a complete stop before the next piston commences its power stroke.

V8 engine is a V engine with eight cylinders. In its simplest form it is basically two straight-4 engines sharing a common crankshaft. However, this simple configuration has the same secondary dynamic imbalance as two straight-4s, resulting in annoying vibrations in large-displacement engines. As a result, most modern passenger car V8s use a complex crossplane crankshaft with heavy counterweights to eliminate the vibrations. This results in a powerful engine which is almost as smooth as the straight-6, while being considerably less expensive than the even smoother and more powerful V12 engine.


The V10 configuration is not an inherently balanced design like a straight-6 or V12. It can be balanced with crankshaft counterweights as an odd firing 90 degree V engine (BMW M5, Dodge Viper). It can be balanced with a balance shaft as an even firing 72 degree engine, or with a split crankshaft journal 90 degree V angle (Lamborghini Gallardo, Ford 6.8 V10).

colm_mcm

JHMEG wrote: »

Rear bank spark plugs a ba$tard to change tho? One of the (only?) problems with transverse mounting a V6.

Mitsubishi do a special tool for them, Luckily mine were done before I bought it, and they're very long life plugs in the back.

E92

JHMEG wrote: »

BTW, nice engine that. And the 4-cyl 4G92. Nice the way the intake and exhaust third lobe can lock up independently, unlike VTEC. Nice the way Mitsubishi licensed the lock up mechanism from Honda too:D.

Interesting that that engine is not at all too distant a relation of the engine in my car. My car has Mitsubishi's 4G93 engine.

But its not a Mitsubishi. So what is it:D?

It revs to 7,000 rpm too, have never tried it, but thats where the engine's rev limiter is.

colm_mcm

some sort of Proton?

Esel

E92 wrote: »

Unfortunately anything with 6 cylinders is very much out of fashion it seems.

I can't understand why, a straight 6 is the most refined and smooth engine this side of a V12. Even V8s and V10s will not offer the smoothness of a straight 6.

Now, a V6 is a much sweeter engine than a 4 pot, but the real benefits of 6 cylinders are found only if you use a straight 6. BMW and Volvo are the only makes that still use a format that should be used by everyone else.

I know that straight 6s takes up more space than a V6 or even a V8, but Volvo can engineer straight 6's that are no larger than a rival's V6, so if they can do it, then why can't everybody else?

The quote below explains why a straight 6 is the best for smoothness this side of a V12

Interesting Wikipedia quote, except for the mention of two-strokes. Anyone ever hear of a two-stroke straight-six?? I thought three cylinders was the max straight config in a two-stroke.

JHMEG

E92 wrote:

I can't understand why, a straight 6 is the most refined and smooth engine this side of a V12. Even V8s and V10s will not offer the smoothness of a straight 6.

Your wikipedia explains why (balance), tho I always thought a 60 deg V8 was balanced. Hence Lexus used it in the LS400. Proper boxer engines are also balanced.

The quote below explains why a straight 6 is the best for smoothness this side of a V12

Remember that smoothness is a quality that is not always desireable. Bit like classical music. Personally I prefer 'Zeppelin to Mozart. When I'm an old fart I might prefer smoothness tho.

You car is a Mitsubishi engine, and going on that it's a non Mitsubishi car it can only be a 1.8 Volvo. Or a Proton of some sort.

E92

colm_mcm wrote: »

some sort of Proton?

Nope,its not a Proton! I like cars, how could I possibly like cars that use ancient Mitsubishi platforms?

That said, my car isn't really a car a car enthusiast would call a proper car(its not that fast and not exactly the best handling car ever to be made),but I'm not stuck in the dark ages so I don't have a problem with it's badge and the sterotype of this make of car is as old and irrelevant as Skoda jokes!

E92

JHMEG wrote: »

Remember that smoothness is a quality that is not always desireable. Bit like classical music. Personally I prefer 'Zeppelin to Mozart. When I'm an old fart I might prefer smoothness tho.

You car is a Mitsubishi engine, and going on that it's a non Mitsubishi car it can only be a 1.8 Volvo.

Spot on! The only reason I have it is because its a hand me down, so I got it for a lot less than I should have.

Its also the fastest car I(afford to) could insure too, so that kind of helps:D.

Being honest, I'm not too bothered by the whole smoothness thing, my love of straight 6's comes from the noise they make, even at really low revs! V6's generally don't sound as good IMO, though thats not to say there aren't V6's that sound as good as a straight 6. I mean the advantage of smoothness is only necessary on certain cars. I'd buy a 6 cylinder BMW over a 4 cylinder BMW just because of the noise alone! The fact that they are faster and smoother than a 4 cylinder is a nice bonus, but it's the sound that does it for me! I'm addicted to the sound of a 6 pot BMW!

In a car like a 5 series or a 7 series, refinement and smoothness are very important, in a car like a Golf GTI or a Civic Type-R who cares about such things? The only advantage of extra cylinders in a car like that is the nicer noise, and thats only me. Then there is the disadvantage of extra cylinder's extra weight. Plenty of people I'm sure will say that there are decent sounding 4 pots around the place(though I've yet to find one apart from the Impreza Turbo).

There are engines that sound nicer than the straight 6, V8s, V10's etc, the only problem with these is that they are extremely expensive to buy and run usually. A 6 cylinder engine is no angel in this department either, but its not too unreasonable.

Thats another reason why I like them.

Gary ITR

Currently driving a TDI Golf (150bhp version) and it peakks at about 4800 rpm:eek:

E92

JHMEG wrote: »

Your wikipedia explains why (balance), tho I always thought a 60 deg V8 was balanced. Hence Lexus used it in the LS400. Proper boxer engines are also balanced.

I'd imagine the reason why Lexus use a 60 deg V8 is because 90 deg takes up more space. Incidentally that is the optimal layout for a V6. The wider the angle, the more space that is taken up. Hence why VAG had those VR6's(because with the 10-15 deg angle, they were really compact). Maybe the V8 in the Lexus is a modular engine, so perhaps all the did was take a V6 and put 2 extra cylinders onto it?


As for flat 6's, I forgot about them and smoothness, they're the same as a straight 6 in terms of smoothness(they make a fabulous sound too, even better than a straight 6 arguably), but they're very expensive(compared to a straight 6) to build.

JHMEG

Lexus chose it because of its smoothness, as the famous champagne glass pyramid ad showed. And I6's in the smaller cars for the same reason. The engine is a bespoke design (not aware of any Toyota V6s from the time), as the LS had to have the best of everything. Altho that engine is physically huge.

Naturally the wider the angle the more space.. a 180 degree V is a flat/boxer! Narrow the angle too much as VW did and both heads are too close and you end up having to cast them as 1 unit, as VW had to with the VR6.

A 6 boxer is as smooth as a 2, 4, 8 etc as a boxer is always balanced, unless it has an odd number of cylinders but I'm not aware of any,