How would one go about building a KA for higher revs. Some say it is not a high revving engine because of the counterbalance but a friend of mine said that a counterbalence helps an engine stabilize harmonics at higher rpm. the valvetrain needs upgrading? how does turbo affect this idea? Id realy like a turbo KA with an 8k redline. am I crazy?

why do you need a 8k redline?

and why is everyone obsessed with higher redlines? first off, the engine has to be able to breath at those RPM's, otherwise it wont make any power, and to breath at higher RPM's you will, almost always, sacrafice low(er) RPM torque and HP, unless you have constantly adjustable length intake runners...(formula one cars, ferrari enzo).

you dont need that high of a redline, and the KA probably wont be able to breath effectively(esspecially under forced induction) at that high of a crank speed, and it also makes bulding a properly spooling turbo that much harder, and I would surmise, make turbo lag even greater.

-chet

not to mention the KA would blow up at those piston speeds due to the LONG stroke, just get a CA if you want a 8k redline with a stock motor.

KA's don't make power up there so it's not worth taking it there, the head, intake manifold, cams, stroke, bore, and everything else are not on your side.

Ca is tempting but not enuf cc's. if i really screw up my ka ill most likely go ca. but I do see what youre saying about the basic layout of the engine. 8k is too far then maybe 7500. just higher y'know how far do you think?. cams would be the first thing to get changed. now what about the intake manifold and head? i see that the ca has a similar intake mani as a honda. is that design better and why?

why would i like an 8k redline? um.....mathhp = tq * rpm / 5252If you make torque up higher in the rpm range you get more hp. the longer you can stay in a lower gear the more you can take advantage of your torque multiplication thru the gearing. power down low is fun but if you want to go fast its better to have it up high.

Why you wand 8k rpm redline ?1. hp = tq x rpm / 52522. Take use of lower, longer gear ratio ( you put more power on ground and less gear changing[lost time] )

To make KA into high RPM, you need a different CAM, valve spring, valve length, different program ECU ( so computer know what to do for fuel, ignition at high RPM ). Blueprint piston and rod, and etc. Port and polish will help it breath better and higher rpm ....

But KA engine is just not a high REV engine. ( due to rod-to-storke ration not in 1.75 [ something with rod ratio... read it somewhere in hondatech.com, not so sure about it ] )

What I remember is 4AGE, B18c, SR20, 3S-GTE, and etc has closer to 1.75 ratio, therefore is very high rev engine.

Or you can get 13B or 20B rotary, which theorically no rev limit :pface

oh yeah, I forgot to add this.

why 1.75 ratio ?Less vibration, ( more vibrate absortion ? ), less cylinder wall bending, crank shalf better balancing .... something like that

Gyfer

not to mention the rod flex on the KA, and the valve angles just are tooooo out of wack for reving high.

A stock KA will destroy itself from vibration at over 7.5K RPM. IN order to pull off 8K, you'ld have to invest a lot of money to get a very well balanced bottom end. The NASPORT GT3 KA's can rev to over 8K but they have a lot of money invested in them. 7-7.25K RPM is safe to do and leaves you some room. Just have to get cams that will breath at that RPM as others have mentioned.

dude, I know the HP formula. but you dont need 8k in a turbo engine, because essentially what a turbo does is increases the displacement of the engine by compressing air into it....that sounds odd, ubt a turbo can force the same ammount of air as a 4.8l engine would inahle at 7k rpms into our 2.4l at double atmospheric pressure(2 bar?).

and "if you want to go fast you ahve to have it up high" is bull****. horsepower is horsepower man, regardless of the RPM's. look at the ferrari enzo, it does 6700rpms, but produces 650hp, and a nice thick torque band. if you want a fast car, you want a long torque band, and a nice horsepower curve, not just high RPM's.

-chet

Torque band, horseower curve and high RPM comes all together.

yea, what gyfer said ^

sorry i meant torque up high which by default means hp.

I would never want a Enzo then. but i also woulnt want an s2000 ether its about balance. and it just seems the ka is a little off balance being as it was built as a truck motor. i am only thinking that people make hotrods out of domestic trucks which drive around revving way high. and wondering if maybe i can do a little of the same. the ka makes gobs of torque, if you could only move it up higher a little you could turn it into hp.8k is too high, i now know and now it seems the concensis is that 7.5 is only possible after extencive lower-end ballenceing. so i shoot for 7250. cams, intake manifold, what else would make it go smoother?

and dont even talk about RE. they are the vile seductress that tempts me every day. I love the way they sound and the theoreticalness and everything but theoreticallness doesnt make for a reliable motor. I do make a decent amount of money but not enough for constant repairs and still have enugh left over for mods. It hurts to see them around town, I want one so bad. but alas it cannot be.

gyfer wrote:Torque band, horseower curve and high RPM comes all together.

uhh....torque band and horspower curve, maybe...but the high RPM thing is a idea behind the engineering, take Vtec/s2000 engines, low displacement high horsepower, low torque, high RPM. obviously all those things dont just 'come together'.

all of the things you say are apects of intake runner size, cam profile, intake size, and much more. manipulation of one can lead to the downfall of another if care is not taken to maintain the aspects you need(such as high flow capability, but low vacuum)....and most high RPM engines dont make good torque bands, or nice HP bands, either, unless they were precisely engineered(vtec engines have a ****ed up power curve, which is hy a good smooth curved car can outrun them very easily)

"2. Take use of lower, longer gear ratio ( you put more power on ground and less gear changing[lost time] )"

dont even get me started on this. have you ever even driven a car with long gearing and not enough horsepower and torque to make it work? having a higher redline does not enable the use of lower gearing, or long gear ratios, ist just means you can revv the engine more, which by itself may or may not produce any more power. you need more overall power and a longer power band to make use of long gearing(like a viper), otherwise you have to use gearing that allows maximum torque to be applied at lower speeds, and more peak HP to be applied in higher gears(such as a low rear end ratio, and gears matches so each shift results in minimal loss of torque and HP when going into the next gear)

Ohhkay, on to your question. you can run 7250 quite easily with breathing mods, stiffer valve springs, and the like. and I havent seen any doemestic trucks being "hot rodded" going high RPM...most domestics dont breath that well to make it work, or ahve the tight tollerances to make use of high RPMS. THe domestics I see just drop in a LS/LT-1 into their truck(corvette engine).

anyways, I dont know why you wouldnt want an Enzo, being able to do 217mph easily, with active aerodynamics(changing drag and downforce constantly with speed, lateral acell, etc)and with 650hp, It seems like as close to a street legal race car as has been produced yet, with tis closest competition being the F40 and Mcleron f-1.

both of which make me want to nut in my shorts.-chetin short, 7200rpms is more then plenty of room to make lots of HP, especially with a 2.4l engine...

hp = tq x rpm / 5252 -> Torque band, housepower curve and high RPM comes all together.

"and most high RPM engines dont make good torque bands, or nice HP bands, either, unless they were precisely engineered(vtec engines have a ****ed up power curve, which is hy a good smooth curved car can outrun them very easily)"

I guess you don't like Honda. I don't like them either, but you can't deny Honda's awsome n/a engine, smart engineer and good marketing. It stock form, with same/near displacement, tell me what "smoooth curved" car/engine can outrun them easily

You high rev a car when you are in race, and try to get max hpas much as possible before switching to next gear. Say 6500 rpm in KA. With proper-good gear ratio, you drop your RPM into 4.5k-5k rpm range, which is at near max torque, with plenty of useful HP.

If you don't have high rev engine, it will drop to lower rpm. say 3.5k . But your usefull HP only kick in when pass 4k rpm. It this case, you lose track time due to waiting for you engine to rev to sweet spot.

To fix that, you change your gear ratio. Now you rev not as high, and still drop into 4k rpm sweet spot, which is good. But in that gear ratio, example 2nd gear, you max speet hit 55mph as your RPM reach 5500 rpm (not high rev engine), you switch to next gear. This cause you to lose track time.

Either one senario will make you lost 0.2-1.0 sec track time in 1/4 mile. not good.

If you don't like high rev engine, you shouldn't chooose Nissan, but get a domestic car instead, like Mustang . Those are low rev engine..... hehehe.....just joking.

Wonder why F-1 Race car has 16000rpm redline. Because those car are not turbo ? hmm.. doubt it.

Yeah, I won't want Enzo either. No high rev ? No fun.

This will be sweet car to have.http://www.turbofast.com.au/lexus.html

Lot's of potential, kick aS-s fast, luxurios and chick dig it !! :icesangel

a f-1 car does 18k rpms because of its design, as per the equasion(sp?) we all know, if you look at the saleen race cars(low revs) their HP occurs lower, thusly the gearing scenario you talked about doesnt matter, because even when chaning gears, from 6500rpm to 4300, they remain in their HP band."if you don't have high rev engine, it will drop to lower rpm. say 3.5k ." no ****. but in a lower revving engine, say a camaro, max torque occurs lower, resulting in less lost HP/torque, thusly no lsot time. and if you look at a powerband of a vtec, its pathetic below 4k....

any racer will tell you you need tos tay at the emat of your power as much as possible, in fact, you even said that, now, in a high revving application, such as a Vtec, the powerband isnt very long, thusly the gearing has to be set very low/close, resulting in lost lap times.

"But in that gear ratio, example 2nd gear, you max speet hit 55mph as your RPM reach 5500 rpm (not high rev engine), you switch to next gear. This cause you to lose track time."

most high revv engine suffer this problem, not low revving engines. high revs power band lay high and tight(spikes), thusly your gearing must be short.

power band is power band, wherever it occurs. me? I want mine long, and occurring as soon as possible, and as much as possible, and smoothly as possible. If you look at the KA dyno, the torque band is flat through from 2500rpm to 6400(on my dyno), compare that to any "high revv" engine, and it give a huge advantage to the KA, or any other engine with a thick torque band...smooth torque band is great for road racning, and evenb etter for drag racing because it allows you to luanch the car better, and pull to 60 much easier.

anyways, hopefully this puts us on the same page, and HP is fun, wether is high RPms nor not (F-1 vs old muscle cars), theres no difference between 500hp at 4000rpm and 500hp at 15000rom man, its all there.

honda snegineers made the Vtec n/a engine to be economy cars first, fun engines seconds, otherwise they would ahve used a single, smooth cam profile, as much of the import racers do(disabling vtec) to get that smoother power band

why would you want to tuned your engine to push your car this fast..?realistically speaking are we talking about testing the landspeed record or breaking the 13 12 or 10 second barrier of a drag race..?or even street racing..? i mean wouldn't you get laughed at if you lost a street race and then blamed it on the fact that you tuned your engine to push your car to 180+ mph..? (and needed a mile to get it to that speed)

besides where in this country can you go over ninety without serious recompence from local authorities(excpet drag strips)?i think good torque throughout the entire range of rpms is much better than huge lag and a high redline? besides there is probably a much better and cheaper way to get the same results with a different setup.

any engineer will tell you if it can be done simpler it's usually better aswell.

:withstup

true that. also, not to be a nit picking *****, but the really high output F-1 days used turbos, renault had a 1200hp 2.8l twin turbo F-1 engine then they regulated it

-chet

"its all about what YOU want the car to do."

"if you don't have high rev engine, it will drop to lower rpm. say 3.5k ." no ****. but in a lower revving engine, say a camaro, max torque occurs lower, resulting in less lost HP/torque, thusly no lsot time. and if you look at a powerband of a vtec, its pathetic below 4k....

Because you never drop lower than 4k when you race ! Gear shifting will always drop after 4k.

I am very very disagree with your answer.

I would NOT say your opinion is absolutely wrong. Is just not in right track. A simple google seach will do a better explaination.

here is one with " hp torque high rev ":

http://www.nissanperformancema...shtml

gyfer

i hate to keep using this thing but it is the best explanation i have found: http://www.datsuns.com/torquehp.htm horsepower IS high rpm torque..kinda. Horsepower is really what dictates how fast the car can go. yes if the engine makes no torque at high rpm it is pointless but that would be changed too.

if the S2000 made more torque at lower rpms it would have lower specific output. period. the only way to increase output at low revs would be to increase displacement or lower its hp. now if you wanted to stroke it you run into the problem of the stock KA design. use a bigger engine overall and you are using the same principal as muscle cars which doesnt work. sure if you want to go fast in a straight line bigger cubes is the way to go.but you STILL want it to rev high(in the article). now lets say your interpretation of "fun" driving involves turning. here there are lots of important factors. suspention design, engine output, weight distribution, among other things. engine output and weight are very closely linked. the engines are heavy. in most cars there is a weight bias to the front. the rare ones that dont are mid or rear engined cars(MR2, NSX, 911 and your beloved Enzo). they can use heavyer engines and so have a balence of low rpm torque and good handling. I dont think an Enzo engine would be much fun in an S2000. well it would untill you try to accel out of a turn and spin off a cliff.

so as the tech article said "It is better to make torque at high rpm than at low rpm, because you can take advantage of *gearing*. " AND in my situation low range torque is plentifull (and will go up significantly with turbo) so i can afford to balance it out a little.

oh and the power on hondas before vtec is not set up for lots of power to create a duality in the charicter of the engine.when you are just cruzing around do you really want the vtec grind that idles all hard and gets horrible gas milage and stalls at stoplights?they only eliminate vtec on real racecars that they never let drop below 4800 or whatever so the low grind gets diched cus its dead weight, impeeding even HIGHER revs. any way you look at it vtec is ingenious. Face it, the high cam creates high rev torque and the low one maintains low rev torque, its an engine variabilty system akin to constantly variable intake runners you think is so cool(and it is). just because it behaves like a 1.6L that doesnt have much torque anyway doesnt mean you should rag on it because it does have torque up high. if there were a variable valve lift and duration system as efective as vtec on our KAs we'd have 200 hp n/a engines WITH good low end torque. a last gen prelude engine is a good example of this.

peak horsepower is not the end-all. upping your higher-end torque or redline at a loss of bottom end is a wonderful thing to do if you drive around at 6 grand all the time.

shifting points are not based on horsepower either, they should be based on torque. you want to shift at the point when your car would produce more torque at the RPM you would be shifting into. this varies with the transmission, rear end, and which gears you happen to be shifting at the time.

and 200 horsepower at 8500 RPM is significantly less exciting than doing the same thing before 6000. it's similar to driving a dodge viper and then an NSX, even a hopped-up one. the viper goes when you want. the NSX acts like an $80,000 1985 accord until you get over 4500. then you might catch up. or you might not.

a good power curve means the ability to say you have a fast car, not a fast car under specific circumstances.

the honda s2000 is a piece of crap...my KAT on the track runs circles around them.....and i shift at 6000rpm

hows that for low revs.....

gyfer wrote:hp = tq x rpm / 5252 -> Torque band, housepower curve and high RPM comes all together.

"and most high RPM engines dont make good torque bands, or nice HP bands, either, unless they were precisely engineered(vtec engines have a ****ed up power curve, which is hy a good smooth curved car can outrun them very easily)"

I guess you don't like Honda. I don't like them either, but you can't deny Honda's awsome n/a engine, smart engineer and good marketing. It stock form, with same/near displacement, tell me what "smoooth curved" car/engine can outrun them easily

You high rev a car when you are in race, and try to get max hpas much as possible before switching to next gear. Say 6500 rpm in KA. With proper-good gear ratio, you drop your RPM into 4.5k-5k rpm range, which is at near max torque, with plenty of useful HP.

If you don't have high rev engine, it will drop to lower rpm. say 3.5k . But your usefull HP only kick in when pass 4k rpm. It this case, you lose track time due to waiting for you engine to rev to sweet spot.

To fix that, you change your gear ratio. Now you rev not as high, and still drop into 4k rpm sweet spot, which is good. But in that gear ratio, example 2nd gear, you max speet hit 55mph as your RPM reach 5500 rpm (not high rev engine), you switch to next gear. This cause you to lose track time.

Either one senario will make you lost 0.2-1.0 sec track time in 1/4 mile. not good.

If you don't like high rev engine, you shouldn't chooose Nissan, but get a domestic car instead, like Mustang . Those are low rev engine..... hehehe.....just joking.

Wonder why F-1 Race car has 16000rpm redline. Because those car are not turbo ? hmm.. doubt it.

also..lets leave F1 out of this issue....the only reason the have engines that rev 14k+ is due to the displacement regulations of that series.....

IF....

there was a race series that was unlimited...you would see ALL big block V8's that are low reving sub 9k..and they would be putting out silly amounts of torque....

WHY..do you think the top fuel dragsters are using these types of motors....duhhh

what you would end up with in a 2003 CANAM type series(not that we will ever see it)...is a mid modified 500-700ci turbo or blown V8..that revs to maybe 8000rpm..laying down 2000-3000 hp, and 2000-3000 ftlbs....that would have a life span of 1-3 hrs...in a F1 type modified chassis

not some 14k+ pissy high revving F1 motor....

IMO

yeah, see...Im kinda done arguing this, I think I've made my point. and I can smoke s2000's also. you want ballanced cars, a ballanced car is not a super high RPM car,..

this is the point I have beens trugling to get across.."and 200 horsepower at 8500 RPM is significantly less exciting than doing the same thing before 6000. it's similar to driving a dodge viper and then an NSX, even a hopped-up one. the viper goes when you want. the NSX acts like an $80,000 1985 accord until you get over 4500. then you might catch up. or you might not.

a good power curve means the ability to say you have a fast car, not a fast car under specific circumstances."

I have driven both, allong with a few ferraris and a lotus esprit twin turbo V-8....the NSX sucks at low revvs. and would lose to all of them on a track(except maybe the viper because the suspension sucks, but thats just my opinion)

anyways, do what you wanna do, if you want to make a 8k engine that losses all its low end, it'd be fin if all you did was road race and stuff....where you never see normal road use....plus, It would be neat to see. so go for it.-chet

oh yes, and on the f-1 thing, I agree if they removed the displacement regs, the displacement would go higher...to a point. at the speeds around corners they run the weight and pure size of the engine(affecting aerodynamics in curves and such) would be an issue...

ADAMHU wrote:the honda s2000 is a piece of crap...my KAT on the track runs circles around them.....and i shift at 6000rpm

hows that for low revs.....

Because you have turbo and S2000 don't. Try S2000 turbo, and they will runs circle around you.

S2000 does have awful low end torque. But with its 50/50 weight , light weight, lower inertia, and double wishbone suspension, it just doesn't make sense you "runs cicle around them"... you have benefit over the turbo ! :icesangel

yeah some new trannies would be needed, and a whoel new design for the rear cowling..plus much larger tires, and aerodynamics as well....BUT..now you have almost 3 times as much torque and HP to punch a hole thru the air...so you can use very silly wings..to increase the cornering speed ever greater than what it is now....

Exar-Kun wrote:yeah, see...Im kinda done arguing this, I think I've made my point. and I can smoke s2000's also. you want ballanced cars, a ballanced car is not a super high RPM car,..

this is the point I have beens trugling to get across.."and 200 horsepower at 8500 RPM is significantly less exciting than doing the same thing before 6000. it's similar to driving a dodge viper and then an NSX, even a hopped-up one. the viper goes when you want. the NSX acts like an $80,000 1985 accord until you get over 4500. then you might catch up. or you might not.

a good power curve means the ability to say you have a fast car, not a fast car under specific circumstances."

I have driven both, allong with a few ferraris and a lotus esprit twin turbo V-8....the NSX sucks at low revvs. and would lose to all of them on a track(except maybe the viper be

cause the suspension sucks, but thats just my opinion)

anyways, do what you wanna do, if you want to make a 8k engine that losses all its low end, it'd be fin if all you did was road race and stuff....where you never see normal road use....plus, It would be neat to see. so go for it.-chet

oh yes, and on the f-1 thing, I agree if they removed the displacement regs, the displacement would go higher...to a point. at the speeds around corners they run the weight and pure size of the engine(affecting aerodynamics in curves and such) would be an issue...

so what....the s2000 has high compression..and high revs....so it would not be a great turbo version car..plus it has those fancy pistons

and NO torque.....its hard to beat cars that have a nice wide torque band....ever go into a sharp corner on the race track where neither 2nd gear or 3rd is good..so you keep it in 3rd..and use the torque to pull you out of the hole......it makes racing easier...cause if you BOG the s2000 down......you lose lots of time....cause it has no bottom end to it....

gyfer wrote:Because you have turbo and S2000 don't. Try S2000 turbo, and they will runs circle around you.

S2000 does have awful low end torque. But with its 50/50 weight , light weight, lower inertia, and double wishbone suspension, it just doesn't make sense you "runs cicle around them"... you have benefit over the turbo ! :icesangel

here are some times from 2000 from a solo 1 event where we had a few s2000's out....and guess what.....in 2000 my car was still NA with 143rwhp and 132ftlbs torque....have a look at the lap times......(and the top driver of the s2000 is a very good driver...and is a former f1600, and f2000 driver..so its the car..not the driver..in fact he got rid of it this year.)

there goes your "you have a turbo" crud...the s2000 was one of the supposed "class killer" cars..and in reality..it turned out to be a huge useless DUD.....

CLASS B STREET PREPAREDThis class was slower then class BSS . Points are based on the best time of BSS .1 John Paczynski GVCC 00 Honda S2000 Toyo 56.617 ( 96.554) 98.2002 Nino Mastrocola TAC 93 Eagle Talon TSi Toyo 57.076 ( 96.803) 97.410 Wheeles Direct/Magnaflow Performance Exhaust/Magnus Motorsports3 Jud Buchanan MLRC 67 Acadian Canso EVO II Yokohama 57.813 ( 95.216) 96.168 Evolution Motorsport/Four Star Racing4 Paul Jappy N HADA 00 Honda S2000 Toyo 59.053 ( 92.889) 94.1495 PJ Groenke N 90 Eagle Talon AWD Tsi Yokohama 59.094 ( 93.415) 94.0846 Jamie Eastman N MCO 87 Dodge Daytona BF Goodrich 65.207 ( 84.896) 85.263 CLASS C STOCK1 Robert Hannah OMSC 96 Dodge Neon ACR Yokohama 59.977 ( 98.393) 100.000 Hannah Motorsports/The Stunters2 Paul Taylor OMSC 99 Dodge Neon Toyo 60.275 ( 98.891) 99.505 Performa Lubricants/Wheeles Direct3 John Dipchand Jr. N BARC 98 Ford Contour SVT Toyo 60.850 ( 97.865) 98.5654 Joseph Kwan OMSC 97 Dodge Neon Sport BF Goodrich 64.498 ( 61.179) 92.9905 Doug Poad OMSC 89 BMW 325i Toyo 65.578 ( 89.598) 91.459 Enterprise Creative Selling CLASS C SUPER STOCK1 Caius Tenche HADA 95 Acura Integra Toyo 58.555 ( 98.635) 100.000 MAX Systems Group2 Ross Ayrhart OMSC 94 Mazda Miata Yokohama 58.860 ( 99.091) 99.4813 Paul Dykstra BAC 82 Fiat X 1/9 BF Goodrich 60.111 ( 96.574) 97.411 Shell4 Victor Gustavison UMN 95 Mazda Miata Toyo 60.520 ( 95.695) 96.7535 Mark Wilson N MCO 96 Plymoth Neon ACR 67.803 ( 84.775) 86.360 CLASS C STREET PREPAREDThis class was slower then class BSS . Points are based on the best time of BSS .1 Robert Smith TAC 92 Acura Integra GS Toyo 57.168 ( 95.974) 97.253 Belzberg Financial/Toyo/Winward Silks/Tireworks/Mad Macs Graphics2 Adam Hutchinson BAC 89 Nissan 240SX BF Goodrich 57.958 ( 94.456) 95.928 Easy DN$/CanaRep/Designtronics3 Brad Merkel N MCO 97 Mazda Miata 60.239 ( 91.493) 92.295

with my turbo set up now at a mild 238rwhp and 255ftlbs....guess what i do to the s2000's now.....yep...run circles around them....

:withstup

-chet

why...do you think the s2000 is a great machine?

This is my two pennies. My 240 makes 158hp at 5000rpm's to the wheels and 148 torque at 5900 rpm's. My friend has a prelude SH with an intake exhaust and he dynoe'd his car on the same dyno I did. He made 192 hp at 6700 rpm's and 137 foot lbs of torque at 62000 rpm's. But I can beat his car every time. My engine gets to its hp curve much faster than his does. We have raced many times and I always get him on the line and he can catch me but I always pull away from him but only by the front tires. So it’s my personal opinion that it’s always better to make power on the lower end to gain quicker launches and to start building Hp right away. Not to wait until 7000rpms to make any kind of power because someone like me will pass you!