SR vs KA

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>>15823726
if you even have to ask dont buy either stupid fuck

>>15823746
I just wanted to hear other people's opinions, dickhead.

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>>15823765
get an rb faggot, 4 bangers are for women and children

>>15823780
>key in the door
Joseph Hui is a shit photographer

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>>15823785
yeah but the skyrine makes up for it

>>15823780
>not LS swapping it
what are you? gay?
https://www.youtube.com/watch?v=U_XoeUi4rdU

>>15823789
i'd like this picture if it wasn't for the fucking stanced tires on a beautiful car

>>15823726
The ka series is a massive bucket of shit you pleb.

>>15823836
Is that why it has more torque than the SR? :^) How about a turbo KA?

>>15823851
>more torque than an sr
im sure it does, try again lol
>torque
double lol

>turbo ka
still a piece of shit truck engine that was only made to be a shit truck engine

>>15823726
Hello Nate

>>15823851
It's a 2.4 with a longer stroke you bellend. It was also used in light utilities so had to have more torque. The SR likes to rev. Ka is limited by its stroke.

>>15823726

Better for what purpose?

If your looking to just get the ol shitbox moving.
You could go through 5,6 ka's for the price of having and sr swapped in.

SR responds better to mods and has a huge aftermarket. Beware, though; internals are fragile from the factory. Spun bearings are common.

KA is a truck engine and its only redeeming quality is that it can take a good amount of boost when it's forged and all.

>>15823889
>Spun bearings are common.
What a surprise from a Nissan petrol engine

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>>15823726

https://youtu.be/9aKPNevTxkk

>>15823832
>stanced

Kek. That is like perfect wheel sizes. Wide enough to fill the gaurds yet doesn't need camber, tyres not stretched, nismo wheels in based 3p 5 spoke. That isn't stance.

>>15823726

SR master race reporting;

Going 1J or LS if i ever blow it up

>>15823726
Meh, I'm gonna be building a high comp, big boost, e85 KA-T when the cash stack is high enough. Only had experience with one SR and it's barely modded. I just think the KA is a stouter motor than the SR. And i personally like the lower revs, higher torque of tbe KA vs the higher revs, lower torque of the SR.
Both good motors in their own ways.

CA :^)

>>15823726
Up to you op, do you want a grenade or a truck motor?

Anyone know if you can put Coupe rear overfenders on a Hatch?

>>15823992
Could always try it yourself or just buy hatch overfenders...

>>15823997

Been asking around is anyone has an extra i can test fit.

The overs i want are a normal whole 3/4 panel for the coupe and dumb ugly rivet RB looking overs for the Hatch.

Do yourself a favour and slap an rb25det into that bitch

>>15824006
Just buy origin lab overs for the hatch. +30mm is noice without going overboard.

>>15823726

SR, KA was a shitty heavy truck engine that somehow made its way into a sports car

>>15824006
What exactly are you doing?

Also try JP Fiberglass. Decent stuff at a decent price. Has RB reps among others

>>15823836
Don't SR engines have massive valvetrain stability issues?

>>15823726
Both are shit. The ka is a utility engine and the sr has been a flawed design from the moment it was released.

>>15823961
Boi it's the angle of the tires, not their dimension.

>>15823981
tfw you like the ca18

>>15823726
KA is a dual cam I4 L-series. If you cut up a pair of heads, you can bolt them onto an I6 L-series to get a dual cam crossflow L28.

Or you can just RB25 swap it like everyone else. SR20 swap is not worth the time, money, or effort.

>>15825742
>dual cam L28
Sounds interesting and also harder than you make it seem

If you do the work yourself and source parts then just go RB25.

Never go RB20 over SR.

Go SR if you want to keep the car and are going to have a garage do your labor.

Stay KA if you are considering the RB as a viable option after what I already mentioned but want to daily it.

KAs are fine if you already know these cars. Anyone experienced with drifting knows that you can clutchkick a stock 240sx for casual 2nd gear drifting.

Good luck!

>>15826477
Not actually that difficult. You don't have to weld the head sections together or anything, oil and coolant flows up and down each cylinder individually. I'm assuming it takes custom cams, though, as well as custom manifolds.

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>>15826504
Quality advice right here

>>15823854
>im sure it does, try again lol

>B13 SE-R with N/A SR20
>136lb-ft @ 4800rpm

>240 with KA24
>160lb-ft @ 4400rpm

Nigga, you dumb.

>>15823726
SR by a mile. it came out in many more nissans than just the silvia. will support up to over 1000hp in turbo form. its a twin cam double overhead valve (chain driven) and has been used in FWD, AWD (GTiR pulsar) and RWD platforms

>>15823828
This is only acceptable if you can't get your hands on an RB25 to boost.

>>15827533
Wow you're so clever anon

>>15827533
>cherry picking an Sr thay didn't even come in a Silvia
Try again

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>>15828058
Thanks?

>>15828068
Filename.

>>15827587
Nail on head

>>15825605

Not massive, but need rocker arm stoppers for sustained high RPM use.

>>15828088
Sr20det makes more torque
Dont call me retarded when you're trying to defend "huur kart makes more torque than an sr"

Its irrelevant anyway bevause Torque is useless

>>15828112

Torque = Force applied to rotating object or force applied from rotating object, measured as Force over Distance

Horsepower = Torque multiplied by speed in RPM divided by 5252

Nigger, you dumb. But I get the feeling you are only pretending to be stupid for bait.

Or you are truly stupid, one of the two.

>>15828130
Horsepower = acceleration
Forever and always the case with more hp will always be faster
Torque is useless unless you're a truck driver

Gtfo with your retarded bullshit

>>15828139

Poor bait, try again?

>>15828142
Dismissing a post as bait because you feel confronted is lame
So tell me again about this ka24de that makes more torque than an Sr20det? And tell me why torque is so important in a light weight sports car

>pro tips
>it doesn't and it isn't

>>15828112
>oh shit, NA SR20s suck at torque production and they came in silvias
>I know, TURBONIGGER9000 to the rescue

Stop being retarded, a FI KA would still make more torque.

>what was said earlier is suddenly irrelevant when the numbers don't match my imagination

Wew lad.

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>>15828154

I'm not the anon you are pissfarting around poofter four banger engines with. I wouldn't use either of these things as a starter.

I'm telling you this though; Horsepower is Torque, multiplied by the speed of the rotation, divided by the constant 5252.

You are dumb as a post and have no understanding of power transfer, you silly cunt.

>>15828161
>moving goal posts
Anon simply said ka and sr
No one uses na sr20s anyway so again it's irrelevant

Next time don't make stupid assertions thay cannot be backed up ;^)

>>15828168
>bbbut this is how hp is calculated
And it's been calculated. After the fact torque remains irrelevant. Horsepower is horsepower.

An engine with more power will always be faster
Torque is irrelevant for performance vehicles

You have rudimentary understanding of performance. Stop posting any time.

>>15828169
The goalposts were set
>>15823851
>how about a turbo KA?
Meaning if you want to compare FI versions the KA still makes more torque. Read more, be retarded less.

>>15828184
>damage control back pedalling
Nothing was said about an na sr. Sr makes more torque, deal with it

>>15823780
Haha western sydney leb detected..

Kebab on lad, kebab on..

>>15828190
>implying the KA making more torque needs controlling of damage

I get it, your ass is chapped. But fret not, you've learned something today.

NA SRs exist, they were placed in silvias, and they make shit torque compared to the KA24.

Again, since you wanted to move goalposts to the SR20DET
>how about a turbo KA?
was already in the post that started this whole discussion. So perhaps you should learn what back peddling and damage control are before you start throwing around buzzwords. Faggot.

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>>15828180

I think you'll find you lack a rudimentary understanding of anything.

Torque and Horsepower are directly proportional. Not my fault this basic fact of power transfer escapes your simple mind.

When you say the engine with more power will always be faster, that's correct. The power applied to the drivetrain is measured in Newton Meters, or in Pound Feet, or another force/distance measurement. The combination with the highest power will often be faster, but not always.

Try again for even half a point? Not doing well here, kiddo.

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>>15825689
Patrician taste, friend.

>>15828214

Should say the engine with more power will be faster, that's mostly correct.

Case of the ol' verbal diarrhea.

>>15828214
>huur horsepower and torque are related in the calculation of horsepower
Yes, your point isn't relevant though
Once measured, horsepower is the only relevant figure for performance

"Muh ka makes more torque even tho it has no power!!!" Is also Irrelevant, bevause Torque is irrelevant for performance:^)
You see my point? Good. Torque is irrelevant

>>15828206
>more damage control
You said ka makes more torque, it doesn't
>bbbut if I move the goal posts
Yawn

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>>15828278

So the turning power applied to the tyres is irrelevant for performance, though it's the rotation of the tyres that propels the car?

You are a basic chappy. You can stop now if you'd like. Or you can keep demonstrating how to dig a hole for yourself without a shovel. You are doing quite well at that.

Again, not interested in your KA or SR. That wouldn't turn the M/E even with the cylinder drains open.

>>15828154
Noone said a turbo sr20 won't make more torque. It was said that an sr20de wont make more torque than a ka24de, which is correct

>>15828298
It wasn't specified whether the det or the de was being discussed

Ok guys

When you're driving a car, you physically can not feel torque. Torque is twisting force in an instant, with no regard for time. When you think you're feeling "low end torque", you're feeling horsepower at a low rpm. You can only "feel" horsepower because it is a measure of work. Peak acceleration happens at peak horsepower, not at peak torque.

A car with lots of torque but not a lot of horsepower will accelerate slower than a car with lots of hp but not a lot of torque. (RPM * torque) / 5252 = horsepower

Having a lot of low end torque doesn't really do anything but widen the power band. And on a track, you only stay in the top 1/4 of the rpm range anyway

Not sure what my point is with this post but yeah. Torks aren't really that important unless you need horsepower at a low rpm eg. towing, or need power over a very wide range of rpms. Which you shouldn't really need to do if your gears are spaced correctly.

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>>15828381
Horsepower is NOT a measurement of WORK. Torque is Force AT a distance. Work is force THROUGH a distance. And that's measured in Joules. HP would have to be Joules/Second, which is abstract and silly.

Horsepower is a completely fabricated number, used by Watt to give an indication of the FORCE AND SPEED applied by a working plant. This is found by taking the FORCE and multiplying it by the SPEED, divided by the CONSTANT. You don't feel this, as it's purely a mathematical equation. You can only feel FORCE, which is measured in FORCE over DISTANCE.

Torque is force over distance. Distance can then be extrapolated to time if you have the speed, if you require it. D=SxT.

Force = Mass x Acceleration. Therefore, Acceleration = Force / Mass.

So when you feel acceleration, you are feeling the effects of Force on the Mass of the vehicle. This can be high FORCE on a low MASS, or low FORCE on a high MASS. When you feel acceleration, it is the application of TORQUE to a MASS.

Doesn't matter how you feel about it, that's a smidgen of power transfer in a nutshell.

Let's say you put your drift missile on a chassis dynamometer. It gives you a Horsepower rating.

The Dynamometer has measured the FORCE applied to your wheels, and the SPEED in which the wheel rotates. It performs the algorithm and gives you the Horsepower rating.

Which is nothing but Torque, multiplied by the rotational speed, divided by the constant.

Having a lot of low end TORQUE means exactly that - you can apply lots of FORCE at low SPEED. If you don't have low end torque, you must have a lot of SPEED to generate the same FORCE.

You cannot over-generalise and say with certainty that "A car with lots of torque but not a lot of horsepower will accelerate slower than a car with lots of hp but not a lot of torque." Not only are they DIRECTLY PROPORTIONAL, but there are too many variables present to say that's true.

Again, Torque and HP are DIRECTLY PROPORTIONAL.

Will you cunts read a fucking book?

>>15826662
>not actually that difficult

If you're fucking hardcore, maybe. Two sets of heads from two different manufacturer part runs off two different cars that have lived two different lives and ergo will have settled differently over their lifetime- It would involve machining the heads in reference to each other rather than an objective point, because I'd hazard a couple thous off would be hell for your snazzy new cams. I remember guys doing something similar for an old Pontiac 6 cammer and I recall them having to fuse water jackets and siamese a few bolt holes, and I'd hazard to say the KA process would be similar- Yeah it can be done, there's the cocksucker out there who cut up 3 KA heads to stick on an L28, but it takes some real engineering.

>ka vs sr
is this 2006 again?

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>>15826504
Rb20 > SR every single day of the week, the rb is unbreakable and the sr is a ticking time bomb however the sr will usually perform better (til it blows)

>>15828457
Not him but you're really bad at explaining things

>read a book

where should I start, oh enlightened one

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>>15828139
>Horsepower=acceleration

>Acceleration is a function of the change in velocity, and can be derived from F=m*a
>F/m=a
>Rotational torque at the wheels would be the force acting on the mass of your automobile
>QED, horsepower=/=acceleration.

You are objectively wrong.

>>15828485

How can I sum it up any easier? F=MA, A=F/M.

Horespower is simply the output of a mathematical equation using Torque as the input. And they are Directly Proportional.

How much further does it need to be boiled down before it sinks in?

Start with Google, you smart ass fuck. If you still have the Year 8 high school physics text book you opened once to draw a dick in it that will probably help you out, too.

>>15828502
You're a dick dude im not even trying to meme.

>How can I sum it up any easier? F=MA, A=F/M.

yeah I get that

>Horespower is simply the output of a mathematical equation using Torque as the input. And they are Directly Proportional.

Don't forget that RPM is also an input to this equation. Also ya you've said they're directly proportional like 3 times. There are two variables though, torque and RPM.

>Start with Google, you smart ass fuck. If you still have the Year 8 high school physics text book you opened once to draw a dick in it that will probably help you out, too.

Cool thanks for the response

>>15828502
is it not true that the maximum rate of acceleration occurs at peak horsepower?

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>>15828542

Yes, it's been repeated a number of times. As it seems that this snippet of general knowledge isn't very general. And it's the entire crux of the system; Horsepower is nothing but a figure derived from calculus to give a snapshot into both Power and Speed, which is Directly Proportional to the Torque generated at that speed.

Yes, RPM is also a variable in the equation. This does not change the fact that the rating of Torque and the rating of Horsepower are Directly Proportional mathematically. That means that the change affecting one, affects the other to the same extent.

As for being a dick, calling out another 'enlightened' cunt sarcastically isn't a great way to meet friends and influence people.

>>15828556

Not in the slightest. Maximum A does not occur at maximum 'arbitrary calculus output.'

Maximum A occurs at maximum F assuming M stays constant. Max acceleration therefore occurs at maximum Force.

If your Force is higher with a higher engine speed, giving you a higher HP rating, cool beans. If Force is highest at a low engine speed, with a low HP rating as engine speed is low, also cool beans. But maximum A occurs at maximum F. Where that lands in your power band is variable.

>>15823889
Lightweight flywheel and turbo WI do loads for a KA. You can build one to 350 hp or so with forged internals, and it'll Rev nice enough.

>>15828485
I found a website that actually explains it well

http://www.lainefamily.com/hp.htm

no replacement for displacement

also the SR is one of the worst sounding engines Ive ever heard

>>15828479
why would you bother with a RB under 25?

>>15828652
rb20 sounds amazing, unbreakable, actually fun as hell in its own way turbo lag is actually kinda fun if ur not racing

>>15828457
>huur horsepower doesn't matter because it's calculated with torque
Literally this retarded Roflmao

Horsepower is all that matters
Summoning ND resident tuner of /o/ to put this 1st year engineering student in his place

>>15823726
The SR is a complete heap of shit and it STILL manages to be better than the KA.

Under Suzuki uses what engine in his s15?

>>15828652
RB20 sound delicious and can rev to the moon.

People compare SR vs RB20 power and they're like 'hurr both 2L why bother', not thinking how much less stroke the RB has and how much better the non-pathetic head design is.

>>15828701
yeah and an RB is 200 lbs more weight placed over the front wheels for a more expensive swap

might as well make it worth it and go 25

>>15828708
At which point you need to change half the front end.

The RB20 is damn near a drop in in S13, you even use the same wiring loom with like 3 or 4 changes.

It's also not 200lbs, it's only just over 100lbs. Worth it considering you can now rev out to 8,000rpm all day happily whereas an SR at 7,000rpm will explode like the heap of shit it is

>>15828673
ND doesn't answer to anyone but ND on ND's terms if ND sees fit for ND. ND out.

-ND

~Post authorized by -ND

Really though, Dan, if you're gonna jerk yourself off, do it in private.

>>15828369
Anyone with half a brain would figure out you would compare an na motor with an na motor.

>>15828771
And anyone with half a brain would realize nobody would bother to talk about or swap an NA SR20

All those factory KA24DETs sure are good though, huh

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>>15828673

I'm a 27th year MAN Diesel and Turbo Kalibrierung Techniker, you peanut.

>>15828771
So now we aren't allowed to compared NA cars to FI? What about the 2.0 skyactiv Miata vs 1.4 multijet Fiat 124 comparisons? Are those immediately invalid? It's the same thing

>>15828792
That's the worst intake manifold i've ever seen.

>>15828812

Not wrong. Cummins KTA-19-M-380. You won't get more than 50pounds/min through that.

Does the job, and is the OEM part, so it's not going anywhere. Don't even know where this tug is in the world anymore.

>>15828792
I remember this anon

>>15828812
>>15828827

The aftercooler is also crammed in there. Just in case it wasn't restrictive enough. You can see the raw water inlet and outlet on the bottom right near the lifting eye.

>>15828830

Bonjour, anon.

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>>15823906
muh nigga

>>15828827
>>15828831
For what purpose, though?

I seriously can't see anyone designing an intake that bad outside of like the 1910s, goddamn

>>15828457
>Having a lot of low end TORQUE means exactly that - you can apply lots of FORCE at low SPEED. If you don't have low end torque, you must have a lot of SPEED to generate the same FORCE.
You're correct all the way up until this point. The problem is that you're forgetting that wheel speed isn't linked to engine speed. Because we have multi-ratio gearboxes, we can convert speed into (forward) force just as easily as we can convert torque into linear force. 100 lb-ft at 2626 RPM through 1:1 gearing gives the same output as 50 lb-ft at 5252 through 2:1 gearing.

Power is the number that unifies speed and torque into a single unit that determines your total ability to create forward force.

>>15828885

Absolutely correct. Seeing as the majority of the conversation was stuck firm on the proportionality between Torque and Horsepower, I thought it best to leave torque multiplication and division out for simplicity.

How you phrased the last sentence is perfect. Power is a number than unifies rotational speed and plant torque into a useable metric. But it seems most do not know how to apply the metric.

I would take my hat off to you, but it is a hard hat, and I will be yelled at for exposing my noggin.

>>15828853

The purpose is simple - connect all six intake ports to a common supply post-aftercooler, with a tight packaging requirement. Marinised diesel engines are often short on space. Not every plant has the luxury of being as exposed as this engine is.

So to keep the packaging small and intake tract length short, a rectangular plenum connects all intake ports. The aftercooler is then mounted above the plenum, and a volute is added above the aftercooler. The volute allows the charge air from the turbocharger to 'roughly' spread evenly across the surface area of the aftercooler.

Service life, then packaging constraints, then operating speed, then output power is the usual flow of prioritisation when powering or re-powering a vessel.

If you think this is bad, don't look at NTA855.

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>>15823726
I diddled SR20's for years and there's not a huge amount of problems with them, quite easy to work on and once they're set up will rev hard all day without doing anything terrible. Most people don't know how to work on them, so they tend to get tangled up in the whole drift-fag thing and end up breaking something 'which must be the engines fault'.
What makes the SR20 a good driving engine is its massive mid-range from 2500-5000rpm that is a bit easier to live with as both a track or road car, that kicks in where you need it coming hard out of corners and launches pretty nice too. That is ultimately the thing which set them above the CA18 and RB20 engines is that tractability, not top end horsepower- but the whole torque curve of the engine.

KA, well I guess you can dump cash into one if nothing else is available, but it'll be quite a lot of cash to overcome some fairly humble origins and making it work for a performance purpose. People do it, they seem happy with them and I'm not really going to talk them out of it. Personally, if I was going down the old timey route I'd use something like an FJ20ET... then go mad trying to find parts.

>>15828950
The problem is that if you take gearing out of the question, you're locking your two hypothetical engines in to the same RPM. Therefore, whichever makes more torque is going to necessarily be making more power. Once you bring in gearing, if you have an engine that's operating in a taller gear (lower RPM) but making more torque, and an engine in a shorter gear (higher RPM), but making less torque, whichever one is making more power will accelerate more quickly (assuming load stays constant). If power is equal between the two, they will accelerate at the same speed.

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>>15829283

This is true, but none of this is a problem. This is simply the very requirement for a torque multiplier with multiple ratios to achieve wide operating speed and why we use them in a car, or the requirement for a single ratio and narrow operating speed.

The real problem is attempting to convey the relationship between torque and horsepower. This is apparently difficult enough without adding the next step, torque multiplication and division, and the step after this, powertrain losses, and the step after that, algorithm offsets for plants operating above 5252RPM and the anomaly that appears when you use Newton Meters in the equation.

Torque multiplication and the results on output power mean nothing but confusion if you cannot understand the base relationship between torque and power.

Image is a 6:1 reduction gear on Yanmar 3000kW, 790RPM unit. For those playing at home, what is the Torque in Pound Feet applied to the propeller shaft?

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>>15828771
When you say SR20, eveyone thinks of a DET, not a DE. Same with a KA24DE over a KA24e

The blu Silvia in pic has a SR20DE & the red 240sx coupe has a KA24E, the Silvia pulls a nose on the 240sx on the highway when roll racing.

(Also neat but irrelivent is the green 180sx had a CA18DET that was swapped for a RB20DET & my cream & black 240sx hatch had a KA24DE, swapped to a SR20DET; so amongst all the cars were the most common engines to find in an SChassis.)

>>15829336
>algorithm offsets for plants operating above 5252RPM and the anomaly that appears when you use Newton Meters in the equation.
I'm not sure why either of those things should cause a problem. Or are you trying to use 5252 for Nm? That's just an easy way to bake in a unit conversion to the question. Power is force times distance divided by time, and that doesn't change based on your units.

>Image is a 6:1 reduction gear on Yanmar 3000kW, 790RPM unit. For those playing at home, what is the Torque in Pound Feet applied to the propeller shaft?
Should be something in the order of 160,500 lb-ft.

Especially for someone working with steady state generators, it should be obvious that torque isn't the important number. If you have a 3000 kW motor turning a generator, that generator is going to be producing 3000 kW (minus losses, but let's just talk ideal scenarios here). 3000 kW is going to charge your battery faster than 2000 kW and slower than 4000 kW, and it'll charge the battery as fast as it's being drained in you're using 3000 kW to make something move. Torque never comes into it, it's just an engineering constraint. If I need a generator to power my building, I don't give a shit if it uses a 350 RPM diesel two stroke or a 35,000 RPM gas turbine. I just care that it fits my size, noise, fuel, and power output requirements.

>>15829506

The unit is a propulsion unit. At 790 RPM, why would there be a six to one reduction before a generator set?

You don't factor torque delivery into generator sets for transient response? That's interesting. We have always been trained to do so. All medium speed 4 pole 50HZ gensets turn 750 RPM with no reduction before the armature. If the unit can deliver more torque than another unit at this speed, the generator set governor will be able to return to target speed, and therefore target output, faster than the competing unit. This means fewer brownouts, VRD trip stops and genset stalls.

Once engine speed exceeds 5252 RPM the algorithm no longer scales correctly without offset. With Newton Meters as the torque value, there is an exponential error that increases with engine speed.

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>>15823726
ITT: samefagging

>>15829781

With 44 posters you're probably not correct, Poofter Pete. But I find the name suitably apt.

>>15828671
only because you dont know the hybrid RB30DET(RB30 block+RB26 head) exists. quite a few been built in NZ

>>15829765
>All medium speed 4 pole 50HZ gensets turn 750 RPM with no reduction before the armature.
Yes, but that's arbitrary. I'm not saying there isn't a valid engineering reason for designing them that way, but a 15,000 RPM turbine with a 20:1 gear reduction could do the same job just as easily.
>If the unit can deliver more torque than another unit at this speed, the generator set governor will be able to return to target speed, and therefore target output, faster than the competing unit. This means fewer brownouts, VRD trip stops and genset stalls.
This is the trap I was referring to earlier. By holding RPM constant in your theoreticals, you're confusing the effects of torque and power. A unit that generates more torque than another at 750 RPM will have more power, and that higher power gives it greater ability to accelerate a given load.
>Once engine speed exceeds 5252 RPM the algorithm no longer scales correctly without offset. With Newton Meters as the torque value, there is an exponential error that increases with engine speed.
What algorithm exactly are you talking about? As far as I'm aware, the laws of physics don't magically change at 5253 RPM.

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>>15829936

The turbine will lack transient response. That's a hallmark of Gas Turbine generator sets. While yes, at a steady state, the gas turbine delivers the same or greater force to turn a specific load at 750 RPM. When the load is drastically increased say by thirty or fourty percent the delay between drop in engine speed from load to resume operating speed will be longer than say, an EMD. That's a hallmark of two cycle medium speed diesel.

The RPM is constant......it's a generator set. That's the whole point - 750 rotations of the armature is 50 cycles a second. The load may increase or decrease rapidly as load is cycled and the governor will add or remove fuel flow to keep engine speed at 750RPM.

And I'm not too sure what you're trying to say here - A unit that generates more torque than another at 750 RPM will have more power, and that higher power gives it greater ability to accelerate a given load - that's kind of the whole point.... How is this a trap? I am confused.

The laws of Physics do not change, but the algorithm does. Watt chose 5252 as a Constant in his Horsepower = Torque x Speed / 5252 algorithm to match his statement that 1 HP is the equivalent of 33,000 ft/lbfs per minute. And at a time where engine speed didn't exceed 5252, so the Constant works. Change the Constant in the algorithm and the definition of Watt's 1 HP would change. You must understand, Horsepower is just a number.

Squiz at the picture here, and please appreciate I have fuck all internet on a computer I shouldn't be using. See how every one of these dynomometer graphs crosses the torque and horsepower curve over 5252? That's a quirk of the equation. Of course if your engine turns to 9000RPM you will have more horsepower than torque, the equation says you must in order to measure 1 HP as 1 HP. And of course if your diesel only turns to 4000, it will have more torque than horsepower.

But sometimes you don't. It's not perfect. How we measure torque is pretty close though.

>>15825629
what is changing camber during hard cornering

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Turbo forged KA
MUH DISPLACEMENT AND USDMTYTE BRO

>>15830014
>And I'm not too sure what you're trying to say here - A unit that generates more torque than another at 750 RPM will have more power, and that higher power gives it greater ability to accelerate a given load - that's kind of the whole point.... How is this a trap? I am confused.
So what if I was an engineer for a company that builds generators, and found that I could save money by putting a 1.093:1 reducer gear on the output shaft of an existing 820 RPM unit? Let's say that despite making slightly less torque (measured at the crankshaft) than a competitor's model, but the extra 10% higher RPM gave it greater power. Which would have better transient response?
>The laws of Physics do not change, but the algorithm does. Watt chose 5252 as a Constant in his Horsepower = Torque x Speed / 5252 algorithm to match his statement that 1 HP is the equivalent of 33,000 ft/lbfs per minute. And at a time where engine speed didn't exceed 5252, so the Constant works. Change the Constant in the algorithm and the definition of Watt's 1 HP would change. You must understand, Horsepower is just a number.
Watt didn't have shit to do with 5252. 5252 is the number you divide by to convert RPM into rad/min. Lb-ft * rad/min = HP. And the reason this doesn't work if you use Nm is because you need to do a unit conversion. One Nm/min = .74 lb-ft/min.
>Squiz at the picture here, and please appreciate I have fuck all internet on a computer I shouldn't be using. See how every one of these dynomometer graphs crosses the torque and horsepower curve over 5252? That's a quirk of the equation. Of course if your engine turns to 9000RPM you will have more horsepower than torque, the equation says you must in order to measure 1 HP as 1 HP. And of course if your diesel only turns to 4000, it will have more torque than horsepower.
So what's changed? Nothing says you can't have more power than torque. Nothing says you can't use the same formula over 5252 RPM and still get a useful output.

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>>15831420

The unit without the reduction gear. And funnily enough, the unit with more torque.

Notice how diesel generators sets are not specified with a reduction gear? 27 years with MAN, never seen one. Never once.

As the aim of medium speed power generation is not only to efficiently convert potential energy from HFO to electrical energy efficiently but to handle extreme transient loads. And a unit with more torque specified at 750 RPM will do exactly that.

So what it you are an engineer designing generator sets? Well, for a start, if I was your employer I would be thinking very hard about training.

Watt had everything to do with the Constant 5252. Here is a quick screenshot of about the lowest source around, Wikipedia.

Why don't you find something out for yourself instead of repeating shit? Twenty seconds in Google could have told you exactly what I just did above - Watt chose 5252 as a Constant in his Horsepower = Torque x Speed / 5252 algorithm to match his statement that 1 HP is the equivalent of 33,000 ft/lb per minute.

Read a fucking book, chappy, before running your mouth. If you're an engineer you shouldn't be designing a drinking straw at this stage.

And I see the point has sailed so far above your head it seems immeasurable. Of course you will have more power than torque above 5252 - the algorithm says YOU MUST. And yes, something does say that the algorithm must be offset above 5252 - JAMES FUCKING WATT advised that it must be offset.

Not doing well here.

And the end of the day, keep doing and believing whatever it is you want. Obviously you do that already and it seems telling you the easily confirmable truth makes no difference, but that's okay. I'll never meet you in my field. At the end of the day you are just incorrect characters on a message board.

Good luck with your generator design. Hopefully you don't use Horsepower as a measurement in your calculations, as it appears you have limited understanding of it in the first place.

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>>15831420

Late to add to this, but of course the unit without the reduction gear will have greater transient response.

Let's assume you close the breakers on the air supply circuit. Load increases and engine speed drops, often down to 710 RPM. This is a reduction factor of 1.056. The directly coupled unit must increase engine speed by fourty revolutions to resume operating speed.

The reduction unit must do the same, and if it's engine speed fell to the same factor as the directly coupled unit, which it will, it would have to increase speed from 776 RPM to 820, an increase of 44RPM. Additional energy must be consumed to match operating speed with the variance larger than the directly coupled unit.

Let's grab your turbine - 150000 RPM with a 20:1 inefficient, power reducing, heat generating, oil cooled reduction box. With the same load applied, shaft speed drops to 14200 (but in the real world, more. Turbines no likey sudden load, compressor stall and all.) The unit must increase shaft speed by 800 RPM.

So which do you think will respond to the voltage slew faster? A medium speed diesel front-loaded with torque, peaking at the operating speed that increases shaft speed by fourty RPM, or a Gas Turbine that does not have the ability to produce this torque AND must increase shaft speed by eight hundred RPM (but likely more)?

Shouldn't be hard to work out which one could keep target voltage +/- 10% for longer than 1500msec and trigger the VRD trip stop. A hint; it's the turbine.

This is but one reason you don't find what you are suggesting in the real world; high speed reciprocating engines with reduction or multiplication gear sets driving generator sets. You are wasting power through heat and mechanical losses, the transient response suffers, and the efficiency of the unit is now reduced. Of course a Gas Turbine set has a reduction gear - 15000 RPM in a four pole gen set is far from ideal.