Looking for advice on my KA-T build...

[Florida240sx]

AZ if you are only wanting 250hp then stock rebuild is all you need.But being you'll have apart get rods and pistons.In case you get the itch in a couple yrs to crank up boost.Just get that along with timing oil and water and your good to go. Mine as well spend the few extra bucks to get the felpro HG.No need to worry about valves being it isn't daily driver or high hp car.You said you got a good mech so everything should be smooth.

[InsanityInc]

Well, what sort of turbo are you running? 220-240whp on 7-9psi is a fairly small one.

Also, your rods won't break or bend at that power level.

One last thing, too: stock KA24DE compression ratio is 9.5:1, not 9.0:1

[nismofly]

t3/t04e, thats what power level youll get out of that boost

i wouldnt consider it huge, but its not that small either

[Nismo_Freak]

Just run on factory compression. No reason to go to lower compression for 7-9psi on a small turbo, that's just wasteful. The stock rods can also handle that no problem. You'll make more power with less boost on the higher CR and also get better milage and drivability. The s15 SR20DET for example runs a 10:1 CR and (I believe) 7psi.

Will your reliability be as good as a stock KA? Not a chance, but regardless of what you build it with it never will be with a turbocharger.

All SR20DET's but the GTiR engines run 8.5:1 CR

A T88H flows the same amount of air compressor side as a T25 at the same pressure. The reason for a power difference between the two is the T88H will have a much larger hotside, reducing the amount of backpressure in the engine. It is even possible for the larger turbo to make less power than the smaller one at low pressures in smaller engines. This is due to both turbine and compressor efficiency models.

[Nismo_Freak]

I would run a forged piston (I suggest CP's) along with a MLS headgasket. Apart from that ARP hardware is nice, and I would go with a nice exhaust manifold paired with a T04E/T3 50-Trim in a .63 A/R housing, externally gated with a Tial 38mm.

That setup would be capable of 300whp all day, and paired with a nice exhaust manifold you can produce it at 10 - 12 PSI.

Go with 50# injectors and a Z32 fuel pump (or walbro), Aeromotive FPR, and other supporting tidbits.

Most people would go with a T3 Super 60 or a T25 / T28 but I feel these turbos are too small for the KA to breath efficiently at the higher RPMs.

[nissanfanatic]

^Fully agree. Tried it, it works.

256whp at 7psi, 326whp at 12psi.

Allow me to add a tuned ECU. That would be something that you slap on and boost away. It may not be the best for max power, but it will run all day long.

[AZhitman]

Alan, I'm glad you popped in.

My turbo specs:

T3/T4, .57 trim StageV wheel on the compressor side, .48 ar Stage III on the turbine side... Capable of 1790 CFM, Garrett BB.

I'm running a Tial 38mm external w/g and an equal-length top-mount exh manifold.

370cc injectors and a Walbro HP/HV pump.

Greddy BOV recirc'ed, and I'm shopping for a Z32 MAF right now (anyone got one? )

I've got the CP pistons and rods ordered, and will add all the ARP hardware as well...

[AZhitman]

Cory, I'll also be looking for an ECU as well... currently have SAFC-II, but I'd prefer a cleaner, no adjustment setup.

AEM UEGO already installed.

[InsanityInc]

All SR20DET's but the GTiR engines run 8.5:1 CR

Nopehttp://driftcentral.com/forum/...=3150

Or if you prefer:

http://www.google.com/search?h...earch

[nismofly]

whats the difference between someones post on another forum and his post here?

the funny thing is every link on the google search but the one you clicked on says 8.5:1

[crzycav86]

Nopehttp://driftcentral.com/forum/...=3150

Or if you prefer:

http://www.google.com/search?h...earch

oh no you didnt!

[crzycav86]

Oh yeah, and hitman: good call on the built motor.

With a setup that can make some good power, you're gonna get pretty curious too see what it feels like.. and you're gonna be glad to have a motor than can handle it reliably. That's just my experience(minus a built motor)

[hazw8st]

Low compression pistons will assure that you don't squeeze the bearing out of the bottom end from overboosting.

[InsanityInc]

whats the difference between someones post on another forum and his post here?

the funny thing is every link on the google search but the one you clicked on says 8.5:1

Uh? No.

http://www.drifting.com/forums....htmlh ... 20det.html

There's more, but all the ones saying 8.4:1 or 8.5:1 are modified engines with a lower compression ratio to run more boost.

[Badfish]

Uh? No.

Uh? Yes. Listen to Nismofreak.

s15 SR20DET stock is 8.5:1s14 and s15 SR20DE's are 10:1

cmon dude, Drifting.com as a source? Anyways, time to get back on topic.

[Jookmasta]

deathwerks for ur injectors...........................but u knew this already. i second the ecu upgrade. its too simple to pass up

[sunnys14]

[QUOTE=Badfish]

s15 SR20DET stock is 8.5:1

QUOTE]

ummm.... sorry but, the s15 sr20det has a 10.0:1 compression ratio

[Charlie240sxt]

your on crack all Sr20deTs have 8.5:1

maybe the sr20de have 10:1

[Craving4Boost]

S15 SR20DET2.0L DOHC VVT Turbo Type: T-28, 60 trim 60 mm BCI-1 compressor in T-04B housingInjector Size: 480cc Power (hp): 250 @ 6400 rpmCompression Ratio: 10.0:1Top Speed: 180 Km / Hr ( with speed limiter installed )Stock Boost: 8 psi

i think i'm on crack too

[nissanfanatic]

And don't pass up simple stuff like rewiring you fuel pump. Simple things like that will definatly eat you up if your engine blows because you didn't spend $10.lol

[nismofly]

Cory, I'll also be looking for an ECU as well... currently have SAFC-II, but I'd prefer a cleaner, no adjustment setup.

AEM UEGO already installed.

since you already have an safc you could get a jwt and use the safc to fine tune, this is the setup Anthony's using to make over 500rwhp last time i checked

i dont know if you even need the safc with enthalpy, but i suppose it could help with a fine tune

[AZhitman]

And don't pass up simple stuff like rewiring you fuel pump. Simple things like that will definatly eat you up if your engine blows because you didn't spend $10.lol

Cory, tell me more... Not sure what you mean.

Thanks!

[hannibal]

WTF does an SR have to do with anything??

The Walbro wiring writeup by Ryan...http://www.ka-t.org/walbrorewire.htmDeatchwerks sells the kit.

I understand your reasoning for building the motor for an extra layer of protection. And this doesnt have anything to do with internals, but you said you want it to be able to handle ~15psi. If youre already planning on a Z32 MAF and a nice equal length manifold, why not add bigger injectors so you really could hit 15psi? You could get the motor running with the SAFC and 370's, then pick up some 50lb injectors when you buy an ECU. The stock MAF will max out around the same time as the 370's (~240-250whp).

Just my 2 cents. Now I'll continue listening to what the pros have to say...

[Nismo_Freak]

Uh? No.

http://www.drifting.com/forums....htmlh ... 20det.html

There's more, but all the ones saying 8.4:1 or 8.5:1 are modified engines with a lower compression ratio to run more boost.

You are arguing about completely unrelated info, and on top of that you are sourcing drifting forums. Need I mention you are arguing about SR engines when you yourself do not own one. I have owned 4 of them, and every car I own is powered by one.

Now, go back to your KA N/a forum and leave the turbo forum to the big kids.

[AZhitman]

Jordan - Thx for that wiring link.

JUST when I think I've got all the bases covered... Dammit.

[C-Kwik]

Low compression pistons will assure that you don't squeeze the bearing out of the bottom end from overboosting.

Low Compression pistons only give you a higher threshold before detonation occurs. While overboosting should not occur if everthing is working as it should, it can of course happen. However, going to lower compression is not necessarily going to eliminate detonation. The additional air in that of itself should not load the bearings up enough to damage them. Even with more fuel(with the overboosting condition) the load on the bearings is not that bad(relatively). Now if you overboost and the injectors are maxed, then you might go lean and detonate. This has much more potential to kill a bearing. And going lean in a low compression motor can still cause detonation which can still ruin the bearings. It's certainly not a way to "assure" the bearings aren't damaged. If you are concerned with overboosting, I'd be more concerned with making sure it never happens in tehfirst place. Choose a good quality wastegate. Make sure flow through the wastegate and back into themain exhaust stream is smooth and unimpeded. Make sure vacuum lines are secure and not in danger of being worn from movement. Give yourself some headroom with the injector sizing. If you're really anal about it, get a pop-off valve that is set to go off with too much boost. I wouldn't use compression as the margin of safety for an overboost. Compression that is too low can affect it's drivability.

[toki]

greg the motor you are building in your head is a motor capable of 600+whp.

stock good condition EVERYTHING will safely let you run 250whp all day, every day, for years and years.

I know "do it right or do it twice." But if you are seriously only going to go to 250whp on it...then there is alot of money to be saved.

[AZhitman]

Understood.

Maybe I'll turn up the boost someday...

I honestly think this car will be an absolute screamer with the 5-speed, ACT S/S clutch, weight reduction, UD pulleys and 4.36 rearend.

[nissanfanatic]

Bearing load is directly proportional to the amount of torque you are making. 350ft/lbs of torque is the same on 10:1 CR as it is on 8:1 CR. It is the same on 87 octane as it is on 116 octane. The real benefit of using lower CR pistons is so you can make more whp on lower octane fuel. I'd undoubtedly go with prolly 8:1 if I coudl find them just so it was easy breezy to make 400whp on pump.

For overboosting...http://www.ka-t.org/overboost.htm

[Florida240sx]

He is telling us onyle 250rwhp.But the reason he wants built motor.Because I suspect at next Nopi he wants to make the crowds' jaw drop with his 400rwhp vert.