I have a really stupid question...

[Rafs-T-Type]

Say a motor is cranking 6,000 RPMS, that's 100 rotations a second...so the pistons are firing 50 times a second?....Something just doesn't seem right here

 

[22lbChevelle]

Yea well the pistons live in a world you don't.

 

[need boost]

yep speedy ain't it lol but your dead on

 

[TurboBuRick]

Actually, on a 4 strake motor, you would only fire 25 times. :tongue:

 

[TurboBuRick]

I meant 4 stroke. No damn edit feature in here.

 

[need boost]

nope its 50 lol, a 4 stroke fires every other time the piston is top dead center a two stroke fires Everytime it is top dead center. Get some more coffee Rick, its early here to hahaaha

 

[TurboBuRick]

I don't know, now that I think about it, may even be less than 25.

If a 2 stoke fires every 2nd stroke and the piston made 50 strokes :biggrin:, the spark would only fire 25 times.

So..... a 4 stroke would actually only fire the plug 5 times per 20 stokes.

 

[TurboBuRick]

I don't know, now that I think about it, may even be less than 25.

If a 2 stoke fires every 2nd stroke and the piston made 50 strokes :biggrin:, the spark would only fire 25 times.

So..... a 4 stroke would actually only fire the plug 5 times per 20 stokes.

Nope, I was wrong. A 2 stroke fires every stroke. A 4 stroke fires every other stroke.
ForgeFX - 3D Four-Stroke Engine Simulation

 

[TurboBuRick]

Getting another cup of coffee now.

 

[need boost]

lol

 

[Rafs-T-Type]

Thanks Rick...you're making me feel better about asking my question

It just seemed like pure insanity that it can fire 50 times a second...sweet sweet insanity ...I wonder how long the spark plug fires for

 

[Rafs-T-Type]

nope its 50 lol, a 4 stroke fires every other time the piston is top dead center a two stroke fires Everytime it is top dead center. Get some more coffee Rick, its early here to hahaaha

From what I've read the piston generally fires before it gets to TDC as the explosion takes a small amount of time to get going. You just don't want too much pressure to happen before the piston gets there otherwise the chit hits the fan

 

[NEVER ENOUGH]

Give you something to think about..lol

Top fuel dragster has a 500 cubic inch Hemi engine that makes more horsepower than the first 4 rows of stock cars at the Daytona 500

It takes just 15/100ths of a second for all 6,000+ horsepower of an NHRA Top Fuel dragster engine to reach the rear wheels.

Top fuel engines turn approximately 540 revolutions from light to light in less than 5 seconds to be over 300mph.

 

[DailyDrifter]

Thanks Rick...you're making me feel better about asking my question

It just seemed like pure insanity that it can fire 50 times a second...sweet sweet insanity ...I wonder how long the spark plug fires for

Probably around the speed of light , but alot depends on compression and gap of the plug. I wonder how many times my Nissan coil has fired in the last 230K , ah who cares as long as it starts up everyday, more than I can say about the Buick

 

[novaderrik]

Give you something to think about..lol

Top fuel dragster has a 500 cubic inch Hemi engine that makes more horsepower than the first 4 rows of stock cars at the Daytona 500

It takes just 15/100ths of a second for all 6,000+ horsepower of an NHRA Top Fuel dragster engine to reach the rear wheels.

Top fuel engines turn approximately 540 revolutions from light to light in less than 5 seconds to be over 300mph.

actually, it takes that long to go from idle speed to the redline rpm- it about half of the run before the clutch is totally locked up- and even then, there is still a good amount of slippage. if there wasn't any slippage, every pass would be a 1000 foot tire smoke show like back in the gasser days.
in other words, they NEVER get all of their power to the ground. i heard one driver or crew chief say that as of a couple of years ago, if they had a tire that could hook up all the power they were making, they'd be running closer to 430 in the 1/4 mile.
which is just freaking insane.

 

[EVIL]

430 mhp in the 1/4

in 1.9 seconds. i want to see that!

 

[Rafs-T-Type]

actually, it takes that long to go from idle speed to the redline rpm- it about half of the run before the clutch is totally locked up- and even then, there is still a good amount of slippage. if there wasn't any slippage, every pass would be a 1000 foot tire smoke show like back in the gasser days.
in other words, they NEVER get all of their power to the ground. i heard one driver or crew chief say that as of a couple of years ago, if they had a tire that could hook up all the power they were making, they'd be running closer to 430 in the 1/4 mile.
which is just freaking insane.

Good god...I'm pretty sure a space shuttle can't touch those numbers It seems like it takes them more time than that to get to a hundred feet (http://www.youtube.com/watch?v=4FROxZ5i67k) - of course they actually outweigh us..Maybe they should have some NHRA guys design the next one instead of having to take the low bidder

 

[CamoDeafie]

um about the acceleration rates of the Space SHuttle versus the NHRA dragsters; you have to consider the action of gravity pulling the vertical down...and then the impact of sudden Gs...I think they DID engineer the crew cockpit to be able to impart around 4-6 Gs or less, by having inertial dampening, kind of like giant shock absorbers....unlike the Apollo/Mercury spacecrafts which probably felt more like the NHRA dragsters then you have the fuel burn rate to lift all that weight, again, compared to the relative lightness of the NHRA dragsters lol. it just looks slow because damn, the shuttle's system is fricking huge. I never thought how big it was until i looked at one standing next to an A-12/SR71 Blackbird, which already is HUGE compared to the majority of fast craft