piston for reliable 300hp-450hp for ka24det??

[dppflyinhawaiian]

what pistons do you guys recommend for a reliable ka24det setup for 300hp daily at 8-10psi and 450hp max?

im think im going to drop the compression ratio to 8.8 or maybe 8.5. but i know that the 8.8 will spool the trubo faster but im looking for power with great reliability, the turbo setup im getting is the jgs starter kit.

thanx for all help

[StylesCD]

Well at the lower end (up to 350) you can keep stock pistons/rods. For the turbo you'd want something like a T3/T04E .50 Trim compressor, .60 trim compressor housing / Stg 3 (aka TA31) turbine wheel, .48 to .63 A/R. At least 2.5 inch downpipe, 550cc injectors, Z32 MAF, etc.

now for 350 to 425 hp you'd want to move to a 3 inch pipe and move to an external wastegate for the turbo, At this point it would be necessary to get new rods/pistons and consider a bore, upgrade to 720cc injectors too and a larger intercooler.

Point here being is stock pistons will be fine until 340+ hp and if you're getting new rods/pistons you might as well go the whole way and get a larger bore.

[WDRacing]

The stock pistons can handle 500 all day. You just can't detonate/knock at all. Forged slugs hold up slightly better then stock units do when it comes to knock. But you shouldn't have knock anyway. You just need a good tune. There are a couple well known Rom tunes available that will allow for the use of stock pistons.

WD

[egan]

i know people say 350 is fine, but what about if you abuse your motor. im on stock block, at 250rwhp on dyno, but when i drift i drive hard, clutch kick all day, stay near redline, and just beat on it. ive got a 3" nascar dual pass rad, and im running e85, i have an oil cooler im about to setup, but i popped 2 motors when i was straight gas on an enthalpy tune, although i was blow through maf which i guess made it lean? (even though i was told on here it would be rich, hence after that motor i switched to e85 and dyno tune w/ safc. wish i owned a wideband) i dont have money for built motor, nor time/effort/money to swap again, but i want to up my power to around 300, 320 would be awesome, just nervous about it. was planning on doing 280, gimme some input

cliff notes: anyone with stock block 350 hp running consistently that actually beats on their motor? (like 2 min of drift not just drag pulls)

[WDRacing]

All tunes should be checked, especially if you plan on beating on the car. That's just common sense right there. I would assume you change your oil after a drift event? Not doing so isn't to smart. Cheap synthetic oil ftw

If the temps are monitored as they should be and the air fuel mix is where it should be the motor should perform very well for quite some time in the 350whp range.

If the above isn't done, the motor failure falls under operator error.

WD

[dppflyinhawaiian]

i have so many questions that its not even funny...

i am going with eagle rods.....estimated to hold 600hp

i was thinking of getting the BC Fully balanced crank for reduced vibration to make the setup more reliable but is it worth-it? or can i just get the stock crank re-surfaced and blueprinted and balanced and will the stock crank shaft be able to hold up to 450hp all day with no problem?

i dont know anything about boring size...+20mm i dontknow what those are or if i need anything like that for my build with my power needs will the stock bore be just fine and reliable for my needs?

i am going with the jgs starter kit w/ .50 trim & .63 turbine A/R. i am also going to get a 3" downpipe. any recommendations on the downpipe? turbo setup from this place http://www.phase2motortrend.com/jgstukitstpa.html

im going to get 720cc injectors, just dont know from who though.

what about my ignition? do i need a better ignition set up than factory in order to start the motor after its complete? any suggestions?

what about the fuel rail? will i need to upgrade that as well? if so what will i need to do so? any suggestions?

i am going to upgrade the pistons for for reliability reasons and for peace of mind i just dont know what compression ratio would be most effective for most power with most reliability? any suggestions?

i am going with the walbro 255 fuel pump.

i was also thinking of going with the brian crower cam shafts... i just dont know what stage to get for my power goals. any suggestions?

i was also thinking of going with the brian crower intake valves. any suggestions?

i was also thinking of going with the brian crower valve dual spring retainer kit. any suggestions?

im sorry i just have so many questions.

any help will be most helpfull

[dppflyinhawaiian]

also, will a apexi SAFC be enough to tune my ecu with for the setup and power that i want? or will i have to get a full tuned ecu? and if i needed a full tuned ecu will it be a problem when it comes to smogging the car?

[StylesCD]

as one wise man said:

OP, you seem to be new to the turbo game. I'm going to throw some pointers your way.

For a 300whp-400whp ka, you don't really need to build your internals. If you have the money and want to for insurance go right ahead. I recommend 8.5-9.0cr pistons for a setup like you desire. Eagle rods will be fine. Stock crank has held over 1000whp iirc, so yeah its fine.

Fuel and tuning is going to be the most important part of your build. A 255lph hp walbro pump, 740cc injectors (sidefeeds dropped into stock rail), enthalpy tuned ecu, z32mafs and safc for fine tuning is a fool proof setup. People have made over 500whp on this setup. There are many other options, you should research alot on this topic and make the best descision for you. Tunable ecu's like calumRT and Nistune are great if and only if tuned by a competent tuner. Your local tuners may or may not be comfortable tuning them.

The jgs kit is okay, there are better options. Its a great kit for a first timer who doesn't plan to push over 430ish whp though. You can get it from jgstools.com with a downpipe.

Cams will really help with top end power. I suggest you stay away from BC, do some research about his cams and decide if you want them or not. I recommend jwt s1 272s dropped in with stock springs/retainers and stock valves. Another good drop in option is kelford.

Your looking at a good amount of money here, so plan your setup wisely. I can't answer all your questions or decide the best options for you. The search function is a great tool and all the information you could ever need is on this site.

[egan]

All tunes should be checked, especially if you plan on beating on the car. That's just common sense right there.

If the above isn't done, the motor failure falls under operator error.

WD

umm WD hehe... zerothread?id=262543

i did the "internet tune check" it didnt work, and i blew up at that event. but to be fair, i didnt have my eye on temps cause i was having too much fun. (im guilty)

after that, i immediately went e85 and went to the dyno, enthalpy tune was all over and way lean after only dropping in 550's(original tune for 370's, 30% larger = 480) drain+fill e85. which it should have been rich just given the size of the injector untuned. but ive been great after safc tune on dyno at 250 (boost has been same whole time 7 psi off wg spring)

but id say im feeling good about ur confidence in 350hp, so im gonna buy a mbc and go dyno soon, up hp to 320/until injectors hit 90%duty cycle, whichever comes first. between 3inch dbl pass rad, huge oil cooler, wrapped ex mani/turdbo/dp, and e85 at stock timing+ rich tune, im feelin good this time

i have so many questions that its not even funny...

BC Fully balanced crank is it worth-it? stock crank will hold 450 no prob

will the stock bore be just fine? any bore is fine with forged pistons, and will meet power goal. more a concern of cylinder wall condition

any recommendations on the downpipe? 2.5+, anything that works

do i need a better ignition set up than factory? any suggestions? are you s13 or s14? if s14, external dizzy is better. try s13 setup, or can get kennebell boost a spark (very effective)

what about the fuel rail? its fine

pistons compression ratio for most power with most reliability? 8.5-9, more of a tune issue

i am going with the walbro 255 fuel pump. good

brian crower cam shafts... stage for power goals. suggestions? v2. can do v3, but tricky to setup, especially considering the questions ur asking

brian crower intake valves. suggestions? not necessary pending budget

the brian crower valve dual spring retainer kit. suggestions? you can do it, but not necessary with v2. do you have a budget in mind????

im sorry i just have so many questions. its cool:bigthumb

any help will be most helpfull

SAFC be enough for power that i want? no, not with 720cc injectors

or full tuned ecu? or go standalone, id recommend the rom tune here though...

full tuned ecu smogging? im from detroit, we dont believe in smog

[hannibal]

after that, i immediately went e85 and went to the dyno, enthalpy tune was all over and way lean after only dropping in 550's(original tune for 370's, 30% larger = 480) drain+fill e85. which it should have been rich just given the size of the injector untuned. but ive been great after safc tune on dyno at 250 (boost has been same whole time 7 psi off wg spring)

Something is quite wrong with that. I dont know much about E85 but 550's with a tune for 370's cannot be lean.

[egan]

Something is quite wrong with that. I dont know much about E85 but 550's with a tune for 370's cannot be lean.

yeah, i agree. its an enthalpy tune, so i have to say having maf as blow through caused additional lean-ness, and not additional richness as suggested. could have been a s***ty tune? i duno