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Discussion Starter · #21 ·
Out of curiosity:

What class of vehicles are you racing against?
(engine size, vehicle weight)

Its okey ..

Until now i just raced my friend

FX 35 V6 ( 3.5L Engine ) 4WD 2009

I raced him with Nitrous 1st n 2nd gear where are together when i shift to the 3rd he goes fastter .

I also raced new Lancer n Honda 1.8 without nitrous and im still having the same problem.

Before i change the Cvt i used to race the same Honda i used to go faster than him like from light to light.
 

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How much experience do you have driving a car with a manual transmission?
It can take a while to become truly proficient, and even longer for you and the car to "become one".
 

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Discussion Starter · #23 ·
Actually its my first time to drive manual for long time coz i always drive auto transmission,

It has been 7 months. this is my longer time to drive a manual.

Even if im not a quick shifter i dont think they would be faster than me,like what happen to me now.
 

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Super Squirrel
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Would the 6 speed transmission fit on the 2.0L?
 

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Super Squirrel
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Absolutely nothing lol just curious. I was just wondering how similar the blocks are between all the models
 

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Over 3k will kill the engine quickly? Define quickly? Say with normal driving an engine would last 300K miles. Maybe with improper maintenece, overextedned oil changes, and a nearly plugged air filter I can see an engine going out at 150k, but I just refuse to believe that extended high RPM operation will kill an engine quickly if it's properly maintained.

Case in point, i've got a 90 Bronco II that has well over 200k miles on the original engine, and the thing sits at 3000 at 70mph. Most of its miles have been spent at slower speeds, in low range due to a screwed up T-case. Consequently, the RPMs sit at around 3500 at 45 mph. We had to drive it like that for close to 3 years before we got it fixed. Aside from a heat warped head 9 months before the t-case gave out, the thing has never had a mechanical engine issue.
 

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These are very lightly built engines, not the earlier generation engines you had in your Bronco II.
Personally, I would never hold this engine (world engine) at 4000 RPM or greater for hours on end.
Most of my driving 70MPH or less keeps me at 2500 or less. (yes - I've had it to 6K a few times, but only to pass or the like)
 

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I really don't see how they're "lightly built". Modern engines have closer clearance tolerances than older engines for decreased wear and friction. That leads us to more power, better fuel economy, and increased reliability.

From my perspective, the only way high RPM operations are going to seriously hamper the life on an engine are if the engine is trying to accomplish a task it was never designed to (eg too small of an engine to move a car effectively), Improper maintenece (a big factor on VVT gas engines and HEUI deisels), or a poorly desinged engine (isufficent lubrication for the given engile load and RPM bands, very sloppy pistion/liner tolerances, bad crankshaft/camshaft/rod tolerances, or low quality parts).
 

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Actually, the "World Engine" was designed to be the cheapest, most generic four cylinder engine available. It was originally intended to be sold to any automaker that needed a low-cost engine for a compact car. The idea was to make up for low selling price by massive sales volume - it does come close. (kind of the Briggs & Straton of the automotive world)
 

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Never said low overall quality - just a plain-jane basic engine.
Fair enough, I seem to be jumping the gun a bit. I still don't see how high RPMs, under redline, can cause much damage unless the engines have insufficent lubrication for high RMP use. In that case, they should have been used for a different application.
 

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An easy test - On a long clear road, take your car up to 75MPH and hold it there in top gear. Take a look at the RPM on your Scangauge - that is more or less the continuous maximum RPM the engine is designed to run at. Higher than that is only for short periods of time. (Hard acceleration, passing, etc.)
 

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RPM - do not hold it at such high RPM's - you'll kill the engine quickly. Even though the redline is high (6500 RPM) the engine cannot run continuously at much more than 3000 RPM for long periods of time.
Don't take this the wong way, but where are you getting that information? Higher RPMs will cause increased wear, thats a given. But, "the engine cannot run continuously at much more than 3000 RPM for long periods of time" just seems made up.

Engine RPM "redlines" are there mainly to prevent engine overspeed scenarios or prevent valves from floating. But I can't thing of a single reason that would cause an engine to fail, if it stays under the fuel cut-off, and doesn't constantly overload the engine. The increased wear is generally marginal and will impact the engine service, but not to a large degree.
 

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OK folks, here we go:

After doing some research and consulting with a couple colleagues in the engine design business.

The maximum permissible piston speed in an engine made of “standard” materials is 28 meters per second.

When a crank is used to change between rotary motion and linear motion, a sinusoidal function is involved (trigonometry).

Without going into great detail, the maximum “mean” velocity of a piston in an engine is 0.707 times the maximum velocity.

So 28 m/s x 0.707 = 19.8 m/s mean velocity.

Good engineering practice dictates that the continuous mean velocity is about half the maximum mean velocity.

We’ll use my 2 liter engine as an example, the stroke is 86mm, and one complete revolution of the crankshaft requires 172 mm of piston travel.

19.8 m/sec = 19,800 mm/s 19,800 / 172 = 115 rps x 60 = 6900 RPM absolute maximum permissible crankshaft rpm (pretty close to our 6,500 rpm redline)

As stated above, the recommended “good engineering practice” continuous running rpm would be about half of the calculated maximum 0r 6,900 / 2 = 3,450 rpm (about 15% above my predicted 3000 rpm)
 

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Super Squirrel
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OUCH!!!! :Wow1: That gave me a headache i hate math lol
 
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