KA24DE(T) Information

[ledzeppelin240]

I have searched and compiled informationa and am now looking for some advice. I have gone with the Real Nissan Starter kit:

**RN Starter kit - KA24DE turbo kit $1,900.00 - includes; RH Cast Iron Manifold (KADE), T3 Turbocharger unit, Front Mount Intercooler 28x11x3 ,Internal wastegate, Downpipe flange and universal downpipe (unassembled), Steel braided Oil send/return kit (w/ all necessary fittings), Cool side pipings, Couplers and clamps, Vacuum hoses and clamps, Nuts & Bolts, Bosch BOV.

If anything missing please notify...

I am thinking about upgrading to 370cc injectors and a Walbro 255 high pressure fuel pump. I only want to run 7-8psi so from what I have read the stock maf is ok...(Mixed thoughts there) and does the ecu have to be retuned?I dont understand the fuel side of a turbo car, I am looking for advice and some explanations(I have searched but am still confused)

[RBS14]

that's a good start.

370's are a must. You are going to want a fuel pump if you are running 8psi, just to be safe. However, you will need a new fuel pressure regulator also, as the stock one can't handle all the pressure from the new pump. Unless you hack your MAF or use a piggyback fuel computer, you will need to get your ECU retuned.

[KOUKI KA-T]

You must get at least 370's. Save your money and buy the 190 pump and use that. Should support well up to 300rwhp or more, and is plenty for 7-8psi. No FPR needed either. Stock MAF will be fine, get an safc or something to control the fuel. You can also go JWT ECU instead of safc, is more expensive but that way you've got timing and tip in retard covered. Hundred ways to do it, all depends on budget and how much tuning control you want to have.

[Bbandit]

I still think going with Wideband 02 + SafcII is one of the best and simple way to tune your fuel..
I should be getting my JWT tuned ECU soon (Its been 1.5 months of waiting)..
Im going to run JWT ECU + Cobra maf + 370cc + Wideband o2.. im gonna get SAFC or somesort in mid summer.

Anyways.. your turbo setup looks pretty good.. just remember to worry more about fuel and timing.
Also, dont forget to get some 02 bungs for the downpipe

[sykikchimp]

Originally Posted by RBS14

that's a good start.

370's are a must. You are going to want a fuel pump if you are running 8psi, just to be safe. However, you will need a new fuel pressure regulator also, as the stock one can't handle all the pressure from the new pump. Unless you hack your MAF or use a piggyback fuel computer, you will need to get your ECU retuned.

FPR not necessary. stock 1:1 FPR is fine, although adjustable FPR's are very nice to have when you hit the dyno.

370's at stock fuel pressure are only good to about 250whp. Your gonna be gettin close with 7-8 psi, and when the boost bug bites, you'll end up need more.

I would suggest something larger like S15 injectors, or 550's, with a 300zx, or Cobra MAF. This will give you some decent overhead.

[ledzeppelin240]

safc...what does that stand for?Also can you guys point me in the right direction as of where to buy an aftermarket FPR(Websites), how hard is it to use a piggy back FMU or what other programs are there out there besides JWT retuning the ecu.

Thanks for all the help so far.

[MELLO*SOS]

SAFC = Super Air Fuel Computer, made by A'PEXi:



http://www.alamomotorsports.com/prod...pexi/safc.html

It splices in between the MAF and the ECU, and allows you to adjust the MAF voltage based on RPM. This allows you to trim fuel +/- 50% in 500 rpm increments, which is great if you have a wideband o2 or go to a dyno that has one.

From above site (dunno who they are, just found in google results):

The second-generation S-AFC is a fuel computer that adjusts fuel/air ratio by modifying the air-flow meter/MAP sensor signal. The S-AFC features a user-definable, eight-point, adjustable fuel curve that can be set in 500 RPM increments. The range of fuel adjustment is +/- 50% at each of the user-defined setting points. On hot-wire vehicles, the Deceleration Air Flow Correction function is capable of curing the erratic idle and stall problems associated with open-atmosphere blow-off valves on hot-wire air-flow meter systems. The S-AFC is capable of monitoring and replaying the following data channels in Numerical, Analog Meter and Graph displays: Intake Manifold Vacuum/Boost Pressure, Air Flow Capacity, Intake Manifold Pressure, Karmann Frequency, Engine RPM, Throttle Position, and Air Flow Correction %. Due to the complexity of this product, A'PEX recommends having the S-AFC and other A'PEX electronics installed and tuned by authorized A'PEX Power Excel Shops.

You sound like you're on the right track.

HTH

[sykikchimp]

there's not really anyone else besides JWT that reprograms KA ECU's for use with non-stock componants.

Your choices for coping with increased fuel demands are: 1. piggy-back computers like the S-AFC, or Greddy E-manage. 2. Rising Rate FPR (FMU is same thing) 3. Hacked MAF, or 4. JWT ECU. (or some combination of those)

Search around on google on what a rrfpr is and search around zilvia (and in archives) for Hacked MAF. You'll find lots of good info. Also buy the book Maximum Boost by Corky Bell. Read it, learn it, live it.

Asking more specific questions will often yeild more productive answers. Good luck!

[ledzeppelin240]

Thanks for all the replies I will be ordering maximum boost as well as searching around more...

[nismo1003]

Originally Posted by sykikchimp

FPR not necessary. stock 1:1 FPR is fine, although adjustable FPR's are very nice to have when you hit the dyno.

370's at stock fuel pressure are only good to about 250whp. Your gonna be gettin close with 7-8 psi, and when the boost bug bites, you'll end up need more.

I would suggest something larger like S15 injectors, or 550's, with a 300zx, or Cobra MAF. This will give you some decent overhead.

then How come the guy in Altimas.net use FMU+SAFC+JWT+720cc = still running dead lean?

[nismo1003]

http://www.altimas.net/forum/showthr...5&pagenumber=3.



Is it really needed?

[yudalicious]

270cc (stock) injectors + FMU are used by one of the companies that make a turbo kit, but I forgot what's their name. Now correct me if I'm wrong, but rising the fuel pressure in stock injectors is an unreliable fuel management choice right? since the injectors will be more prone to failure right?

[sykikchimp]

that's correct. You will also get atomization problems when the fuel pressure gets too high.

As for that Alty thread, "cthunder" is an idiot. If his system is "Dead lean" it's b/c he hasn't tuned something properly, or his injectors are running at 100% duty cycle and have gone static.

A larger injector dumps more fuel at the same pressure for the same given pulse width as a smaller injector. No need to increase fuel pressure unless you need to make a smaller injector work like a larger injector.

[Dream240]

Originally Posted by sykikchimp

that's correct. You will also get atomization problems when the fuel pressure gets too high.

I didn't read that whole thread but I can say that "cthunder" is an idiot.

Okay so IF you had a Walbro fuel pump, OBX FPR, and stock injectors on a NA KA24DE, what's a good pressure to run the FPR at? 25psi? 40 psi? NO one seems to know this answer. Also if I got upgraded injectors, 370cc, would this cause my car to run too rich?

I'm planning a turbo someday, I got the fuel pump cause I needed a new one and my current mods are really all air mods, no fuel delivery mods except what's listed above.

[sykikchimp]

how much boost do you plan to run?

is this the FPR your talking about?
http://cgi.ebay.com/ebaymotors/ws/eB...category=33554

If so, that appears to be an Adjustable fuel pressure riser, not a "Rising Rate". It won't work for what you are talking about.

[pr240sx]

Where I can find that kit??
sounds too good to be true!!

[sykikchimp]

Originally Posted by sykikchimp

there's not really anyone else besides JWT that reprograms KA ECU's for use with non-stock componants.

Your choices for coping with increased fuel demands are: 1. piggy-back computers like the S-AFC, or Greddy E-manage. 2. Rising Rate FPR (FMU is same thing) 3. Hacked MAF, or 4. JWT ECU. (or some combination of those)

Search around on google on what a rrfpr is and search around zilvia (and in archives) for Hacked MAF. You'll find lots of good info. Also buy the book Maximum Boost by Corky Bell. Read it, learn it, live it.

Asking more specific questions will often yeild more productive answers. Good luck!

I should have also included info about other forms of fuel management like additional injector controllers and Standalone engine management. One is very expensive, and they both require extensive tuning.

[Dream240]

Originally Posted by sykikchimp

how much boost do you plan to run?

is this the FPR your talking about?
http://cgi.ebay.com/ebaymotors/ws/eB...category=33554

If so, that appears to be an Adjustable fuel pressure riser, not a "Rising Rate". It won't work for what you are talking about.

Yes that's the one I have. Now educate me, what's the difference between Adjustable fuel pressure riser and a "Rising Rate"?

And why won't it work?

Thanks

[BlackFox]

I believe the adjustable fuel pressure riser allows you to change the fuel pressure by a set amount. It does not vary with the changing requirements for fuel pressure as you boost. A rising rate will vary the fuel pressure as you need it automatically. Cause when you boost more, your fuel needs increase.

~Jeff

[Dream240]

Okay, so the FPR I have will work for my NA set up for now right? Since I'm not boosting yet, my fuel needs are constant. My biggest concern now is my fuel injectors. Do I need bigger ones to go with the increased pressure from the FPR and the pump? I've heard that larger injectors on NA cars will make it idle rough and perform poorly. Question is how much bigger can I go before this happens? Or do I even need to worry about my injectors for now?

Don't forget my cars current setup is NA.

Sorry ledzepplin for jacking your thread a little, but I can't find these answers anywhere.

[RBS14]

sykikchimp: You don't need to get a new FPR when you get a walbro 255? Everyone I've talked to says the stock FPR can't handle all the extra pressure.

[Var]

Originally Posted by Dream240

Okay, so the FPR I have will work for my NA set up for now right? Since I'm not boosting yet, my fuel needs are constant. My biggest concern now is my fuel injectors. Do I need bigger ones to go with the increased pressure from the FPR and the pump? I've heard that larger injectors on NA cars will make it idle rough and perform poorly. Question is how much bigger can I go before this happens? Or do I even need to worry about my injectors for now?

Don't forget my cars current setup is NA.

Sorry ledzepplin for jacking your thread a little, but I can't find these answers anywhere.

you dont need bigger injectors. If you fully maxed out your KA as far as n/a performance goes which is like 180-200rwhp, you can still use stock injectors with a bigger fuel pump. Dont worry about injectors right now.

[Dream240]

Cool,

Thanks I figured as much cause I've been running this setup for the past 1500 miles and no problems. Since putting in these fuel upgrades, I've noticed better pull at WOT and steadier revs while accelerating.

I'm gonna go turbo withing the next year I'm just planning on a bottom end build up first. Pistons, head gasket, rods, rebuilt crank. It'll be a beast.

Thanks!

[sykikchimp]

The stock FPR is fine, there is no increase in pressure, the FPR maintains pressure at 43.5 PSI all the time no matter what the fuel pump does.

you don't even need an upgraded fuel pump unless you increase fuel pressure.

Increasing static fuel pressure will make your injectors act like larger injectors, and will make your car run rich unless you compensate for the additional fuel the same way you would for larger injectors.

That FPR is pointless.

[Var]

**RN Starter kit - KA24E/KA24DE turbo kit $1,900.00 - includes; Our custom manifold (KAE) or RH Cast Iron Manifold (KADE), T3 Turbocharger unit, Non- intercooled, Internal wastegate, Downpipe flange and universal downpipe (unassembled), Steel braided Oil send/return kit (w/ all necessary fittings), Cool side pipings, Couplers and clamps, Vacuum hoses and clamps, Nuts & Bolts, TurboXS blow off valve.

- T4 turbo, external wastegate, assembled 3" downpie upgrade. Add $500.00


This is from Real Nissan. It seems you are 500 short on your pricing. The price you state in non-intercooled

[Dream240]

Originally Posted by sykikchimp

The stock FPR is fine, there is no increase in pressure, the FPR maintains pressure at 43.5 PSI all the time no matter what the fuel pump does.

you don't even need an upgraded fuel pump unless you increase fuel pressure.

Increasing static fuel pressure will make your injectors act like larger injectors, and will make your car run rich unless you compensate for the additional fuel the same way you would for larger injectors.

That FPR is pointless.

Okay, I understand what you're saying but here's what I'm trying to determine if it's even worth it. Say the pump operates at 80 psi, then you would have 80 psi from the tank to the FPR right? Then from there to your injectors, the FPR runs at 47.5 so the end result is 47.5. BUT if you increase the FPR pressure to say 60 psi, this will cause the injectors to act like larger injectors correct? So would this require the addition of say an S-AFC unit or similar computer upgrade to correctly utilize the upgrades?

I don't mean to beat a dead horse I just want to get my concepts clear.

Thanks

[sykikchimp]

yes. that's correct. You would treat them exactly the same as larger injectors. So an S-AFC, or the like would be necessary. If you did increase fuel pressure like that, then you would need an upgraded fuel pump.

You can calculate the new flow of your injectors with this equation:
P1 = original pressure
P2 = New pressure
F1 = original flow
F2 = new flow

F1 x √(P2/P1) = F2

270 x √(80/43.5) = 366.15cc/min
so about a 74% increase in flow

that would support about 280 flywheel hp, or about 240whp.

Word to the wise though, forcing an injector to work above it's specified work load comes with some risk. It is advisable to use properly sized injectors rather than try to do it with fuel pressure.

One thing.. the fuel rail feed is the front of the engine. The FPR is on the back, with a return line hooked too it. Any flow that would result in more than 43.5psi (or whatever you set your adjsutable fpr to.) of pressure in the rail is returned to the gas tank.

[Dream240]

Thanks sykikchimp.

[andrave]

ps, you won't get 240 whp out of stock ka injectors.
and thats a shitty way to try and do it anyway.
if you must go FMU get an adjutable one and forget the SAFC, if you get an safc I don't see the pointof the FMU.
You can get 370 sr injectors for the price of an fmu.
or you could hack the mafs for the price of injectors...

[RBS14]

Originally Posted by andrave

or you could hack the mafs for the price of injectors...

Damn, that's a pretty expensive hacked MAF. The tube I got cost me $5.