higher RPM range

240s are pretty low on the RPM red line 6500, V8 engines are about the same, if i do internal work to the engine how do i know where the redline moves up to? Dyno is the way? Whats a good way to move up on RPMs? Since im putting in a greddy turbo with forged and lower compression pistons, paying some good money for my internals that can handle some heat, but does that actually more my RPM up?

Polished out head and intake manifold will help the air go in faster and will that improve the RPM range?

Thanks for the info.

theres no need to port and polish the head on a ka24de

theres no need to port and polish the head on a ka24de


y not? i have an extra head laying around that i was going to do for fun lol....just want to know why thats all.....i mean it couldnt hurt. plus its kinda dirty in there anyway.

yea why not?!!

dont you just love these replies from people who just go .... " no i dont think thats a good idea!" without any reason behind their statements lol :nono:

I don't see why a port and polish would not benifit any car to some degree... as for the Higher RPMS? Probably not. All you are gonna get is a better flow and some HP with a Port/Polish...

better valve springs will raise the actual redline, to what, I dont know. The spring manufacter usually will advertise. An aftermarket cam will raise your torque curve to a higher RPM so you can benefit for the raised redline. The valvetrain is usually the factor that determines redline. At a certain RPM the valvesprings cant close the vlaves fast enough. On "interference" engines this causes the pistons to run into the valves and boom. On a "non-interference" engine it just keeps the RPMs from raising.

to safetly raise the redline you need to get stiffer valve springs to prevent valve float at higher rpms. also you would need a cam that breathes good up top. becsue if you do that with stock cams the cams will choke out the engine at that speed which will in turn lead to making less power. however goin too crazy with the cams will make your car idle like shit since we have no variable valve or cam timing. also you need to rebalance the whole rotating assembly to allow it to spin more freely with less vibration. the main limiting factor will be the long strong of our engines. since the piston travels more distance for each stroke. even though the engine is reving not as high, the piston speed is higher then a lets say honda's pistons speed would be becsaue they have a shorter stroke. and when you over rev an engine like that, your goin to spin a rod bearing and throw that rod right thru that block.

to safetly raise the redline you need to get stiffer valve springs to prevent valve float at higher rpms. also you would need a cam that breathes good up top. becsue if you do that with stock cams the cams will choke out the engine at that speed which will in turn lead to making less power. however goin too crazy with the cams will make your car idle like shit since we have no variable valve or cam timing. also you need to rebalance the whole rotating assembly to allow it to spin more freely with less vibration. the main limiting factor will be the long strong of our engines. since the piston travels more distance for each stroke. even though the engine is reving not as high, the piston speed is higher then a lets say honda's pistons speed would be becsaue they have a shorter stroke. and when you over rev an engine like that, your goin to spin a rod bearing and throw that rod right thru that block.
someone knows their shit

:icon16:

thats what i was thinkin, jesus

Can a rod bearing actually go through an iron block? If it can then that's scary, what's stopping it from going through the firewall into your leg or something. lol (besides the firewall)

The momentum of the rod is going up and down not side to side.....i donno what would cause the rod to go horizontal. but yea that would be scary shit if it were to happen

my friend had a grand am and he put 150shot of NOS to it and blew a piston thru the block....dumbass.....i didnt see it myself.....but i hear from other people about blowing pistons and rods thru the block all the time.

what are pistons made out of.....cast iron, steel, aluminum....i guess i've never really thought about it. but if pistons are made of iron lets say and the block is aluminum then i agree that a piston or rod would go thru the block because iron is stronger and denser than aluminum is. Or else if they are both aluminum then maybe the monentum and force of the piston is soo great that it just blows thru the block no matter what. i donno...im just going off of simple physics.

as you noticed my name GT500916 916 is my are code and GT500 is the car, so i have this 67 stang and i blew a rod out before and it chipped the block, and its possible to blow the rod out from the side, mine busted a hole in my oil pan size of the wrist. i had to buy a new engine because the shipped engine was just done with :) ... thats my story with iron blocks, strong as they are, they are not rod proof!!

....what makes the rod shoot out the side?

The way my engine got blown is this... my mustang "didnt" have an RPM gauge old school 67, well i pushed that engine to about 7000+ rpm and one of the rods gave in. The weakest part in the engine is the rod C clamps. When i took my engine out and apart i saw how it happened. The piston itself actually got jammed in the cylinder wall and the rod could not be pushed any further so the C clamp just gave out and that just smashed and bashed all the parts that went flying inside my block hahaha... my first words were "WHAT THA!!? HOLY CRAP!!!" followed up by a big puff of smoke and an oil trail for about half a mile LOL!!, thats how far i was from my house when the engine blew, i actually thought it was my trany so i threw it in neutral and cruised at idle home!!! :D

I used to live in the 916! The best runz I've been to are in sac over on florin rd. but yeah TatII dont say that stuff again you just scared the crap out of me!! :eek2: jk I dont know much about engines so everything you guyz say is just stuff learned. :icon16:

i got a friend with a 96 turbo KA. and he windowed his block. his con rod got torn in half and it ripped right thru the side of his iron KA block all the way down thru the oil pan.

here is a pic.

http://www.geocities.com/ultraredka240/oilpan.jpg

http://www.geocities.com/ultraredka240/holeinblock.jpg

http://www.geocities.com/ultraredka240/oilpan1.jpg

it might sound scary. but i mean what you should do is to just not rev the eng that high to make power. its just not designed to do it reliably. its soo much easier to just put boost to the KA to make power rather then goin the n/a route

and the story about this engine. this is his 4th KA. he originally turboed the stock engine, then destroy the rings in cylinder #3. this was because his internal wastegate had a problem and he had boost issues.

so he put in wiesco pistons, and a cometec metal head gasket. however when he rebuild the engine he droped the pistons from the oil pan instead of taking out the whole engine and decking the head and the block, and he didn't rebalance the crank shaft and the new lower compression pistons 9:1 was causeing a balancing problems. he also didn't bother changing the head studs. and he also didn't hone the cylinders. this would've ensure a proper fitment of the rings and pistons.

with the new engine he decided to run 10-15 psi. however he didn't do anything about the ignition timing. he didn't hook up a timing light or anything.

he then detonated soo much that he destroyed the spark plug in cylinder #3. the pieces of the plug broke a hole in his piston.

3rd engine. he blew a head gasket

4th engine he changed the head gasket himself but he again left the studs and he just tore that engine apart too many times. so he was boosting 13 psi ( mind you again w/ithout any kind of spark retardation device ) and he his rod shot out of his block. what my theory is that he was detonating soo much it weakened the rods ( which are good for 20psi of boost ) and it just couldn't take it anymore. again it was cylinder #3 that want bad.

Talk about Whoa... How much did you spend for DRT to tune your car for you? and what did they do if you dont mind me taking this thread more off topic?:D

i added alot more to my past reply. you should read that first







and about my car being tuned by DRT. when i put in the 370cc injectors. the car would idle and run fine off boost becasue i set the low throttle settings to -28%. becasue the 370's are 27 percent larger then the stock 270's. i also was flooring the car to see the behavior and i was leaning out the car more and more at high boost. the leanest i had the balls to go by is -15% at high rpm. however the car was still bogging from running too rich. the car was also blowing out black smoke from ru nning too rich on boost. when i initially took the car to DRT. he looked at my settings and they looked about right to him. then he put the car on the dyno and put the wide band 02 sensor in the tail and went for a initial run. the car was blowing out black smoke like crazy and my first pull only put down 189whp. after 28 pulls later, i had a peak of 247whp and averaged high 230's. however it was getting late, the car was getting heat soaked and we couldn't get that magical 247whp to come up no more. so i settled for the lowest # which was 232whp becusae i figured i'll lose a few hp to run more reliably. this was before i added more stuff to my car. the price that i paid for the tuning was $250. it was well worth the money since in the end i gained about 40-50whp. the tuning took about 1.5 hours of continuous dyno pulls. i'm curious to see what my car makes now but i don't feel like spending $100 to just see what i'm making now. that was about a year ago when i had it tuned.

Thats pretty cool to hear and the price for the tuning isnt bad at all. Initially I want to get as much power to the wheels as your KA can, But I will have to wait and just hope for them dayz to come :sadwavey:

Luckily the KA24de valvetrain is built pretty good, more sturdy then the SR valvetrain. Stiffer valve springs have already been covered, they also make titanium retainers that are stronger and lighter then the OEM ones, these two things together do not raise the redline, they just allow you to rev a little bit higher without fucking anything up. Of course to do any of this you need to retune your ECU to accept the new limmiter and cut off points.

the reason you do not need to port and polish the heads is because the KA24DE head is one of the freest flowing stock heads known to man. It will put a SR's head to shame..(now that sounds like guys arguing over woman haha) some guy spent over a grand on a real nice professional maximum port, valve angle job, and polished all the runners, and gained 2rwhp..yes thats TWO. Doing stuff like that to a v8 or so would net about a 50hp gain... you won't gain hardly anything, DEFINTELY not worth the price, spend 1200 bucks on something else, it will be a more worthy purchase.

so with all these great features, how come the KA is so whimpy stock? Well in actuality its not too bad. It puts down more power then a B16 honda motor. If you raised the compression for say a 20hp gain, not too impossible, you would be up around a B18's power output. So whats the weak spot? It has great displacement, strong rods(yes u have heard about some of them failing, if u treat an engine wrong any rod will break), long rod ratio, and the head and valvetrain design is excellent, not too mention the iron block... its the CAMS nissan used that derates this motor. Buy some forged pistons for about a 12:1 ratio, basic engine overhaul kit, some decent gas, some of the stage II NA cams, computer tune, lightweight pulley, intake, header, catback and valve springs/retainers, ditch clutch fan for electric setup... you would be amazed at how different the car will feel. With a LSD, some lighter wheels, wider tires, decent clutch and maybe even a lighter flywheel, this setup should be in the 13's with a decent driver, and it doesn't even cost that much really, most of the parts you would buy for a turbo setup, and the other ones you wouldn't are cheap compared to turbo accessories and the actual turbo.

thats what I would do if I had a 240sx......

but im saving up scraps for da Cadillac Fleetwod......
soon to be seats laid back, v8 rumbling, brakes that would astonish u for a 5000lb beast(better then a 240sx atleast muhahaha) and handling that will leave u saying, wtf is this a caddi?
:rofl:
southern pimp style

hahaha a FLEETWOOD?!?! thats like the longest 4 door car i've ever seen in my life!! its like almost 20 ft long!! after you got your impala SS you seem to be more of a n/a buff now. don't worry sometimes i do miss the induction growl of a intake. but for a 4 banger. i'd take turbo anyday.

remember having no turbo is like having infiniti lag. you can always use more boost. even if your already making 600whp. the turbo will put you in the 900whp range.

One: The rev limit of the motor is based on rotating and valvetrain integrity.

Two: a long stroke doesn't mean it has a lower rpm limit. you can counteract the effects of a Long stroke with Longer rods. The theory of Longer rods keeps the Piston in the top of the bore alot longer which lowers cylinder temps, slows the piston speeds, and allows for higher compression ratios with less chance of detonation.

Three: The KA valvetrain is actually really solid but hampered by balance issues. The major problem is high speed chain rattle causing valve bounce which causes a loss of hp.

Things to do on a ka to increase RPM Limits properly.
1) Full head work ( Includes Port and Polish, High speed Valve grind for better sealing, Head deburring, Bowl Polishing, etc.)
2) Larger/Lighter pistons
3) Longer Lighter Rods
4) Full rotating Assembly Balance, Crank Edging and Lighting and if budget permits Full Counterweighting
5) Cooling and Oil Ports Enlarged for More volume and flow
6) Cam speced for RPM Area and increased load
7) Stiffer/lighter Valve springs and retainers
8) rocker arm stoppers
9) Higher Temp / Harder Valves
10) Higher Flowing Oil Pump
11) You also want to Tackle the Timing issue
12) Ignition system/ Intake Manifold/ Exhaust Flow all Need to be addressed to give the motor its full potential.

i blew a piston out the side of my block....left a hole that your fist could go through....as for the piston it was never found totally gone, i even searched for it on the high way, poor piston. so that is y i have a whole extra engine basically, except for well the BLOCK, so thats y i wana go for the KA-T setup.

hahaha a FLEETWOOD?!?! thats like the longest 4 door car i've ever seen in my life!! its like almost 20 ft long!! after you got your impala SS you seem to be more of a n/a buff now. don't worry sometimes i do miss the induction growl of a intake. but for a 4 banger. i'd take turbo anyday.

remember having no turbo is like having infiniti lag. you can always use more boost. even if your already making 600whp. the turbo will put you in the 900whp range.


a 94-96 Fleetwood is pretty much an Impala SS frame. The only big differences is that the rear shocks are airbags---which change over very easily from an Impala ss.. which I already have the best impala springs and shocks made just laying around. Also the rear differential is a lower ratio, and has drum brakes on the end of the axels... well this is another simple cure haha... I also have a rear end off an Impala SS with disc brakes, upgraded 3:73 gears, and the best u can get really EATON clutch lsd installed masterfully...hey while im at it, why don't I just stick the entire rear end assembly from the Impala on there, suspension and all that would cure all my problems..... cept thats gonna cost me about 1500 bucks.

The headers I want to get are 900 bucks... but they really are the best you can buy, the quality is awesome, the fitment is stock, the finish looks brand new after 2 years of use on some other guys Impala, and they make MAD horsepower, like +30 over stock..just from a set of headers lol. So im gonna get a new hooker catback system, no cats, hotchkis springs and QA1 shocks, and some aftermarket brake pads... When all that no longer makes my dick hard Im gonna go for some roller rockers +20hp, and Hotchkis Lower Control arms which help out a lot on the handling. Im gonna build up a transmission with shift kit, and a 2500 stall torque converter.......

with all this done Im expecting a high 13 second 1/4 mile slip, around .95g+ lateral grip(impalas already do .88 stock... throw on better and bigger tires, springs, shocks, and it makes a HUGE fuckin difference, you would be amazed at how good it can grip the road.... its just not as agile as a lighter car.


NA is the way to go man, totally different driving experience. To all these import kids who swear by their turbo 4's its obvious they have never really driven a high horsepower v8 car with a decent chassis a lot. Now im not saying a camaro is badass or anything.. don't put words in my mouth..cause they suck bad... But LT1 powered B-Bodies are a different breed. there is no comparison between a N/A v8 and a turbo 4... its like russian and english, sure some ricer might have driven his dad's v8 pickup and thought, geez this isn't fast or that good, my civic is faster..... well don't let that fool you... cause if u drove just one 4 cylinder car and based your opinions on all 4 cylinders off that.. you would be pretty dellusional, especially if the 4 banger u drove was a 104hp f22 honda motor HAHHAHAHHA..

its a totally different driving experience when u can light the tires up right away as soon as u press down the pedal, or when the 400lbs of torque from 2000 rpm can push you through any gear like a turbo only wishes it could.

Displacement owns joo

your right TaT turbo's can always add power, but seriously after driving even midly built up v8 vars, a twin turbo v8 is going to be WAY to much engine for the street, would be a hell of a ride on slicks down the 1/4 though.


Fleetwoods OWN... 20 feet lmao.... they look even better dropped down a few inches, with a louder exhaust, and hauling ass past you...
one of the best sleepers ever made I think.

i missed gears in my old sil80 quite a few times, tach went up to 9k (no rev limiter). also shifted at 8k a couple times. stock internals, no ras.

no probs.. yea it was really scary having no rev limiter but i wonder if it every did any damage.

when you get an aftermarket ecu people, make sure it has a rev limiter... if it doesn't you might be sorry. sorry if im a lil off topic :)

well, if you have bored your engine that could cause a rod to go through the side given that you throw one, generally though they will end up goin out the bottom or jamming up somehow. as for one goin through the firewall, i dont think it is possible unless maybe if you had your rpms way up on a banked fwd. but yes at higher rpm's you can throw a rod or a bearing and screw up your motor, if you wanna get more rpm's get it balanced and blueprinted and possibly some new bearings and forged rods as well. and if im not mistaken, forged pistons are made out of aluminum, it has a great heat dissipation and they are light.

lol. why????

Buy some forged pistons for about a 12:1 ratio, basic engine overhaul kit, some decent gas, some of the stage II NA cams, computer tune, lightweight pulley, intake, header, catback and valve springs/retainers, ditch clutch fan for electric setup... you would be amazed at how different the car will feel. With a LSD, some lighter wheels, wider tires, decent clutch and maybe even a lighter flywheel, this setup should be in the 13's with a decent driver,

uuuh.... did u say 13's with bolts on on a Ka?
i have T28 BB, piping (intake, Front mount, ...etc) boost at 1 bar, F-con, 550cc injectors, stock BOV, Kaaz 2 way stock clutch, einky (whatever rims, 225 tiers (azainiz's sport) Tiens coilovers, cusco strut tower bars, tein tie rod and conecting rods, nismo engine mounts
Koyo radiator, Hks ground wireand ... no a/c

i'm running 13.3... i'm not the best 1/4 dude...(not a drager, when one w/ freinds and didn't like it, rathere drift / grip) STILL i don't think a na KA can touch me...

my freind has a KA24DE w/ all piping & advanced timing... MAN DO I rape him (lol, Reyota!)

anyways, i think it will run 15's not mid 13's.

oh yeah , forgot to say ...i have SR blktop..

you rape KA's?.......i just hope you dont get flamed too bad....

noooo way that would be 15's. id say 14's tops probably dip into 13's. a stock 240 with JUST intake can run 15's

actually fuck that that would definitely be 13's solid. 12:1 and cams with ECU+everything else? c'mon that would definitely be 13's.

Forged pistons are made of aluminium? Dude they would melt!

im not totally sure, but i think they are, they have aluminum blocks and they dont melt, aluminum dissipates the heat better

They have steel sleeves in aluminum blocks.

oh, that i didnt know, i do know however that my dirtbike which has an aluminum cylinder, but i do beleive its nickel plated. im pretty sure that they do make aluminum pistons, but ill check to make sure, i dont think they would melt though, they dissipate heat too fast.

Why do you think Boyd Coddignton's Alumi-tub has an SS exhaust? Because it would melt if it was aluminium like the rest of the car.

ill check on it and get back to you tomorrow

i found some aluminum forged pistons on ask.com, i typed in aluminum forged pistons and i went to only one, but it said they used it in a race application. so they do make aluminum forged pistons, and appearantely they dont melt.

yeah bro they have aluminum pistons. normally its *copy and paste "high-silicon enhanced 4032 alloy (with additional Cu, Ni & Mg)" but yeah theres aluminum.

thank you, however am i right about the heat dissipation?

Yeah, aluminum does disipate heat rather well, that's why when you wrap something in aluminium foil and stick it in the oven, you can take it out with your hands. Anyways, for the pistons, they must be coated with something and like orestes said, it's an alloy because they would melt if they were just aluminium.

you rape KA's?.......i just hope you dont get flamed too bad....

no no, don't get it wrong... T KA is fast my car is not that fast, but i know for sure that KA24de with piping will not run 13's no way.
my freind runs 15's with the Ka and piping... i ran him and it was not even a race. in 1st gear we where next to each other, 2nd i just lost him, 3rd i'm gone...
he is going to get T3/T4 , so i think it will trun around soon...

i wasnt saying piping! i was saying with head work, cams, ECU, rebuilt to 12:1 compression.... thats about a 75 hp jump. But I dont know how long you could run 12:1, probably have to rebuild it every couple months. The cams, higher compression, and everything is like 98984843003% different from just Intake/Headers/Exhaust..... :screwy:

KA's are friggin slow, get an SR. SR ownz everything. 2.0l engines flow more than any other engine on the planet. Even the viper engine.

12:1 compression will last for a long time as long as the tune is good. With 6psi, the CR of a 9.5:1 NA CR is 13.4:1. Head work=waste of time on the KA. Even with a turbo application, gains are minimal. Cams and intake manifold are the bottleneck.

WTF do you guys mean by piping? Exhaust? Intake? What?

yeah i think he meant I/H/E. and not necessarily just port and polish the head i agree do the intake mani and throttle body too.

I know for the SR20DET you can put in an SR20DE thottle body to get gains, but what can you put in the KA?

you just bore it out.

Yeah, but can you really bore it out that much? I mean aren't throttle body walls thin enough as it is?

lol i have no idea how much they do it, but boring out throttle bodies is pretty common. my guess is like a 10% overbore?

he has a KA-t and hes only running 15's?? He just sucks then...or, are you saying hes GOING to go KA-t??