Engine sound.

[Coventrysucks]

all you wanted to know abotu blowing an engine up with a tiny misfire

I watched one of the Top Fuel funny cars detonate its supercharger during the burnout.

[jcp123]

and just for the quarter mile?

Yes. These engines are over 600ci, IIRC, running somewhere in the neighborhood of 14:1 static compression, and then has the supercharger on top feeding it a LOT of boost - not sure how much, bu tit's safe to say it'll be at LEAST 20psi. They rev to over 10.000rpm (not bad for a so-called "old overhead valve lump", eh?), running on Nitromethane to produce the power.

[henk4]

Yes. These engines are over 600ci, IIRC, running somewhere in the neighborhood of 14:1 static compression, and then has the supercharger on top feeding it a LOT of boost - not sure how much, bu tit's safe to say it'll be at LEAST 20psi. They rev to over 10.000rpm (not bad for a so-called "old overhead valve lump", eh?), running on Nitromethane to produce the power.

What would the piston speed at 10.000 revs? (what is the engine stroke?)

[jcp123]

No idea, I haven't looked at the stroke size, but I'm willing to bet it's very high (probably at least 7000ft/min). The weak point on these cars is actually probably not the bottom end, however, but the valvetrain. The botton ends I think use special 6- or 8-bolt cross-drilled mains, with some of the strongest wrist pins and rod bolts you've ever seen. But the rocker arm assemblies are pretty fragile, so they have to use special rail-mounted rockers rather than the normal pedestal mount. And for all I know, there is even some further girdling done to them to maintain stability.

[henk4]

old formula III OHV engines (1000 cc screamers) also ran up to 10000 revs, but they were rather short stroked.

[got hemi?]

Hmmm well this one time at Fallsington day a Mustang (68) pulled into the end of a closed off road, turned around drove right up next to me, and reved its engine up Wow my ears rung for like 15 minutes afterwards. It obvously had some aftermarket parts.

[Fleet 500]

What is the best sounding engine that you have ever heard, modified or not?

A 426 Mopar race Hemi with open headers.

[jcp123]

old formula III OHV engines (1000 cc screamers) also ran up to 10000 revs, but they were rather short stroked.

Yeah, I don't think you could get away with 600 cubes on only 8 cylinders with a short stroke inless you have like an 8" bore. Which I don't think they're running.

The 302 Ford can be easily be built to take 8000 revs, and if you have the money, I have seen one capable of 11.500.

The point being that while most OHV engines are tuned to run at low revs, that does not automatically mean they are incapable of it.

[henk4]

The point being that while most OHV engines are tuned to run at low revs, that does not automatically mean they are incapable of it.

Just that you mentioned it as the main problem for running at 10,000 revs

[jcp123]

Alright, couldn't resist posting a few of my favorite inline 6's. With a V8 thrown in the mix for good measure

Here's a '50 Ford running a 226ci Flathead Straight Six. Runnin through Smithy's pipes.
http://exhaustsoundclips.com/phpbb2/...ile&file_id=97

Here's a Ford 300ci Inline 6 with a fatty cam in it:
http://www.bigblocksix.com/f100swb/cammed.mp3

And another clip of the same 300-6 going offroading:
http://www.bigblocksix.com/f100swb/offroadin.mp3

Here's a 65 GMC with a nice sounding 6, goin through 1st and second gears:
http://exhaustsoundclips.com/phpbb2/...le&file_id=160

Here's an LS/1 Camaro with one of my favorite exhausts for it, the SLP Loudmouth:
http://exhaustsoundclips.com/phpbb2/...ile&file_id=46

And last but not least, here's a '50 Plymouth Business coupe with a 230ci Flathead 6 during restoration, just after it got put it, goin for its first cruise:

[GTR Dreamer]

subaru

[Fleet 500]

subaru

[thinker]

subaru

he's probably talking about the wrx...im not sure about stock, but a friend of mine has a wrx with a magnaflow exhaust system and it sounds surprisingly powerful. i sort of expected the typical buzz u get from a rice rocket with a modified exhaust.
...you can hear a wrx with a magnaflow exhaust setup on this site... http://www.magnaflow.com/04sound/04sport.asp
...just click on the WRX w/o resonator and silencer launch file

[thinker]

he's probably talking about the wrx...im not sure about stock, but a friend of mine has a wrx with a magnaflow exhaust system and it sounds surprisingly powerful. i sort of expected the typical buzz u get from a rice rocket with a modified exhaust.
...you can hear a wrx with a magnaflow exhaust setup on this site... http://www.magnaflow.com/04sound/04sport.asp
...just click on the WRX w/o resonator and silencer launch file

could the powerful sound be a result of its boxer engine? anyone know?

[Matra et Alpine]

No idea, I haven't looked at the stroke size, but I'm willing to bet it's very high (probably at least 7000ft/min).

close ( nearly had me confused as I'm used to using metres/sec on fast moving components the doubel conversion from 30m/s had me thinking it was way out - BUT a wee check of the following url and all is revealed )

See http://www.davewin.com/tech/mean_piston_speed.shtml for an easy calculator ...

... so acording to the specs on Bill Miller cars, peak power revs 8000 and the stroke is 4.5" that gives a piston speed of 6000 ft/min or 100 ft/sec
Both close enough for another engine able to do 7000

The weak point on these cars is actually probably not the bottom end, however, but the valvetrain. The botton ends I think use special 6- or 8-bolt cross-drilled mains, with some of the strongest wrist pins and rod bolts you've ever seen. But the rocker arm assemblies are pretty fragile, so they have to use special rail-mounted rockers rather than the normal pedestal mount. And for all I know, there is even some further girdling done to them to maintain stability.

yeah the have to beef up the valve train as well as the bottom end, but not half as much !!

The rods and the small-end are the weakest points. As you cant' afford to beef them up as much as you can the big ends - coz the small-ends are MOVING MASS and they need that low !!

It's the hydraulicing issue that causes most to let loose IIRC.
So one misfire and the engine explodes because if they fuel does NOT burn then the next intake mixture brings in more fual mix and it NOW is dense enough to become all liquid before the end of the compression cycle. Liquids dont' compress ( as much as gasses ) so it pushehs the valves through the heads, splits the heads or just plain blows the head OFF.