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File: IMG_3546.jpg (242 KB, 1268x507)
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How can a V8 rev at 7800 rpm for 500 miles?
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why can't it?
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>>28868291
>7800 rpm
Thats some rednecks's turbo LS build, Stock car engines redline at 10,000 rpm.
>How can a V8 rev
Engineering and a lot of money in fucking around and finding out AKA RnD. Idk if they use nitrogen/pneumatic based springs or traditional ones but springs are probably their bottle neck everything else is just money (lightweight rotating assembly and valvetrain)
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so can my shitbox motorcycle
(it has to, 65 mph is ~7000 rpm even in top gear)
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>>28868307
what kind of third world country are you from
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>>28868291
Ford's Indy V8 ran at 20,000 RPMs and had to be governed to 16k by race rules.
>2.65L turbo DOHC V8 making 800 hp in the 60s.
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>>28868291
The engine components are made out of very expensive materials compared to what's used in typical road vehicles, which are typically both lighter and stronger.
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why do euros and poors think all pushrod v8s are of the same build tolerances and efficiancies as they were in 1964?
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>>28868335
forged crank and rods and internally balanced
it's not fucking rocket science
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Something something bore and stroke something. Shorter stroke can rev higher.
>>28868311
That exhaust manifold is a thing of beauty.
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>>28868342
European's also have V8 cars themselves making it even weirder.
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File: nascar malibu.jpg (238 KB, 2048x1286)
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>>28868291
Pushrods = pushgods
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>>28868342
Because the ones in road cars are.
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>>28868342
they basicly are. they can still rev it just takes some work. LS, LQ and the equals of the other brands, chrysler "hemi", ford modular or whatever they got today, i dont know? they aint redesigned from the old v8, just refined. and a good refine for most of them but they all rely more on inches of cubic than actual engine development to make their power. and none seem to look into diesel seriously. last and only good american diesel was the 80s 7,3idi.
you can today buy a4 or 6 cyl diesel in europe that will outperform a bigger v8 gasser in usa.
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>>28868291
It's easy - just drop $75K+ on a custom-built engine.
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engines at that level of competition get complete torn down and rebuilt after a race.
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>>28868409
>redlines at 8 400 r/min
>mutt: i-impossibru
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>>28868291
Watch the tour Cleetus just did of RCR. The amount of precision and quality control that goes into their engines is insane, on the level of NASA shit or top-level university research labs etc. They reject parts for flaws you can't even see without a high-powered microscope.
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>>28868310
probably america where a lot of highway speed limits are 65mph.
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>>28868487
literally in a thread discussing the opposite
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>>28868291
You know that NASCAR engine's can run 10,000 RPM for a short periods of time right?
Most of the time on Super speedways, they're turning 9,000 RPM.
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>>28868433
>outperform a bigger v8 gasser in usa.
Stay Jealousy my Friend.
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>>28868291
0 weight oil and tight clearances.
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>>28868605
on super speedways they tend to run closer to 6800, restrictor plates makes their torque curve max out there. on nonrestricted tracks yeah it's over 9000.
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>>28868311
>>28868367
The tiny RC car engines rev to 45,000 RPM and are air cooled.

Also yeah second guy got it: large bore, tiny stroke. Horsepower= (torqueXrpm)/5252
The indy car engines have basically no torque and why they 'easily' stall from a dead stop even for modern machines.
Its the inverse for diesels: they have very high torque and don't rev very high so an 800hp diesel has orders of magnitude more torque. Longer stroke compared to the bore.
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>>28868674
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>>28868304
You don't need light weight for high revs you need the right material and enough balancing/gap tolerance/oil pressure control. Conrods need to be strong for higher rpms which is why bigger rods or titanium are what handle the specific forces rods deal with.
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>>28868682
you can have a diesel with a larger bore vs stroke, and end up with a diesel with a more power than torque. the Audi and Peugeot LMP cars were like that. in their case, they were tuned to have a completely flat torque curve that hit max torque at like 900rpm and stayed there to redline.
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>>28868682
>The indy car engines have basically no torque
Fucking retard.
Pic related is the Indy.

HP doesn't exist.
Its extrapolated from torque measurements. You literally cant have HP without Torque.
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>>28868693
Off boost, those engine make sub 200lbft
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>>28868702
What the hell does that mean?
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>>28868731
I wondered that too, man. You can't go WOT without engaging the turbo, and taking the turbo off would require entirely new tuning so it'd be multiple variables. Are we just imagining the turbo isn't there? lol
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>>28868291
That's the challenge, isn't it?
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>>28868310
Ninja 250s were sold in America until like 2012 and they spin 10k rpm at 70mph. They got replaced with the 300 and then the 400
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>>28868780
sure but a 250 really isnt made for 70mph if we're being honest (isnt it more like 8800 rpm?), and the progression up to 400cc was because those small high running engines are too hot and can't meet nox emissions spec.
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>>28868291
The pushrod V8 in this can rev to 11000rpm and it survived a 1000 mile desert race powering a 7000lb truck. I really don't know where the "hurr pushrods can't rev" thing comes from. Picrel is 16.5 liters and still revs to 8000.

https://www.youtube.com/watch?v=u6pAjjXNr7I&t=
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>>28868731
>>28868738

He's talking about the engine being easy to stall - low rpm off the line with minimal/no boost + gears for a high top speed.

Peak number doesn't matter, if you're measuring performance at a given point. "Area under the curve" type of observation. Just like a 240hp 5.7L v8 and a 240hp 2.0L S2000 are radically different in personality. Those peak output numbers are meaningless for how how he's discussing their performance off the line. You'd need a torque curve and the gear ratio spread to really know.
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File: 20160728_123423.jpg (2.01 MB, 2539x4068)
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>>28868783
>(isnt it more like 8800rpm?)
no, it's not.
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>>28868803
>He's talking about the engine being easy to stall - low rpm off the line with minimal/no boost + gears for a high top speed.
That does make perfect sense. But, 200 lb-ft is still quite a lot down low unless first gear is exceedingly tall.
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>>28868803
this is why I personally prefer C4's with the gen 1 smallblock over the LT1. at the time everyone foamed at the mouth over the LT1 being over 300hp but the car feels better in normal "area under the curve" driving with the sub-300hp gen1 engine.
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>>28868790
Euros are an entire continent of dunning-kruger. stupid, aggressive, ignorant, and smug about it.
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>>28868810
your own choice of pic and some 2nd grade math gives 8930rpm for 70mph so....no it isnt 10k...
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>>28868693
Remember these are 1600lb-1800lb also.

>>28868491
NASCAR's technical level is a lot higher than you might think if you have no exposure to it. Take a look at their job postings sometime if you have a technical bent.
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>>28868827
retard, which one of us actually owned the motorcycle? I've put 10k miles on Ninja 250s, I know what they rev to. Wrecked a timing chain on one because I ran WOT all the way across Minnesota on I-90 with it
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>>28868841
ok chatgpt
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>>28868816
That's interesting anon. Curb weight's about the same, right? Torque curves really do matter. I liked the C4 at the time and they're getting just old enough now to have deep classic vibes.
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>>28868847
you are a double nigger
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>>28868310
'straya
got a 250 little V-twin

>>28868783
they work well enough. Maybe because mine is a V-twin it gets a little lower gearing, but the redline is 11,500 and holding 7 or 8000 seems to be just fine for the motor.
A 250 is about the smallest I'd take on a highway though. There's hardly any acceleration if you're in top gear, but it can do it.

>>28868810
your own pic proves it's about 8800 retard, you're going 90 in it so of course it shows more revs
that said the speedo is probably a few % high but that won't change much
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File: NASCARvalvespring.mp4 (3.93 MB, 1920x1080)
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>>28868491
Was going to post about this as well, some cool stuff in there
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>>28868829
>Take a look at their job postings sometime if you have a technical bent.
I'm on the wrong side of the country, but it's definitely something that's crossed my mind, I've got a background in motorsports (club/pro-am road race shop) and I'm currently going back to school for machining and have a definite bent toward the more precision/technical side (and may end up transferring for an Engineering Technologist BS) so it'd be a logical thing to look into.
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>>28868291
What's the team's engine allowance for the season?
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>>28868650
what am i to be jealous about? we can and do have anything you make here, plus we got all the sweet euro and jap diesels you dont get. its you who should be jealous.
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>>28868433
>you can today buy a4 or 6 cyl diesel in europe that will outperform a bigger v8 gasser in usa.
Cite an example of this.
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>>28868816
>the car feels better in normal "area under the curve" driving with the sub-300hp gen1 engine.
Based TPI. I like to think of it as the "long tube header" of intake manifolds as dumb as that sounds
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File: 20260301_202742.jpg (2.22 MB, 4080x2296)
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>>28868433
>all rely more on inches of cubic than actual engine development to make their power

Life must be hard for you, being that dumb. I honestly feel bad for you.

Also, even if you were right, why is that a problem? It's obviously a valid and effective strategy. You just don't like it for some reason. I drive on the street, not the track. I'm not governed by displacement limits. So why should I limit myself there? Because it would be fair to faggots like you that are limited by displacement? Yeah I don't fucking think so. Get bent, pushrods push gods, and remember there is no replacement for displacement. Only cope.



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