engine/fuel management for KA-T

Post by **fiznat** » Mon Sep 08, 2003 9:16 am

alright alright, I KNOW this has been brought up 1000+ times, but dammit Ive been searching alot and I would really like to get a definitive answer based on my setup... So please try to resist the urge to flame, and just help me out if you can...

I am planning a KA-T on stock internals for my 150,000 mile car. Yup, you read right. 150,000. It's stock internals for now, but I feel like if I keep the boost around 7psi and I tune it right, I shouldnt have too much of a problem until I can afford to build up the lower end. My ultimate goal is to build something capable of about 300hp at the wheels, maybe more if I buy quality parts. For now though, I will be happy with 7psi intercooled on stock internals.

My question, though, is what I need to do as far as fuel/air managment and timing. Basically from my searching and reading, here are the things that I should consider buying:

-Fuel Pump-Injectors (size?)-Fuel rail (depends on injectors I guess?)-Rising rate fuel pressure regulator-Something to monitor my ratios: S-AFC or E-Manage or what?

I'm not sure which of the parts in that list I will NEED for my current application. I have talked to lots of people both on the boards and at shops, and everyone says I will need different things- ranging from none of the above to all of the above.

Based on my goals and your experiences, which parts do you think I need - and what brands/sizes of them do you think I should buy?

Thanks alot for reading, I know its a long post but please help me out!-

Post by **bbandit** » Mon Sep 08, 2003 9:16 am

150k? thats not muchim going ka-t with my 166k 91 KA lol300hp@7psi?well i think you should stay away from RRFPR (FMU)seeing that you're gonna run 7psi (right at the edge for the FMU to be working properly) but i guess it'll be alrightS-afc is a "nice to have" if you're planning on using FMU (altho it'lll make tuning a biznatch)aside from fuel, dont forget about timing.. 3 degrees retard should be fine but its nice to have an MSD BTMfor 7 psi.. i think you dont need super duper expensive fuel management but if you're planning to go for more boost in the future.. why not go with standalones from the start?e.g.SDS standalonehttp://www.sdsefi.com/prices.htmlYou will want the EM-4F for 4-cylThe EM-4E can be used, but it uses the stock distributor and requires a MSDbox and coil. The EM-4F is definitly the way to go, though.You'll also want the following accessories:Knock sensing, fuel pump relay, electric fan control (if you want electricfans in the future), 2-BAR MAP sensor, and maybe the fast-idle if you haveA/C. Also note the price of the Extra Injector controller as analternative.

after totaling the final cost.. i bet you wont even touch it LOL1600 bux is just too much huh?for now, im going with FMU since im gonna run only 5 psibut eventually, i will have to force myself to get this SDS standalone..

OR

you can make yourself your own EFI systemhttp://www.bgsoflex.com/megasquirt.htmlA DIY EFI system I'm still investigating. looks kinda promising!

so back to the topicfor your setup that you're planning right now..i think it will be fine with370ccwalbro 255lph fuel pumphacked mafs (or Z32/cobra mafs)S-afcmaybe MSD BTM

good luck!

Post by **Structure240sx** » Mon Sep 08, 2003 9:16 am

with a walbro 255lph fuel pump and begi FMU i was ok upto and past 9psi. it was once i fixed my spark plroblem it boosted to 11-12 psi and ran lean. im sellin the FMU now cheap since i have a fully built engine adn 740cc injectors

Post by **Silent Drifter** » Mon Sep 08, 2003 9:16 am

7psi just get some 370cc injectors from a SR, get the walbro fuel pump, an get a SFMU. (note not an FMU)

Post by **SingleCamSam** » Mon Sep 08, 2003 9:16 am

Why would he even need an aftermarket pressure regulator for 370's at 7psi? I don't even see why he'd need the fuel pump (other than mileage) if he's going to run the stock fuel pressure.I'd get the 370's, hack the MAF, adjust the base timing and leave it at that. Maybe an S-AFC, since Orion is running a little too lean with the hacked maf from 2500-4k. Just a thought, do more with less.

Post by **fiznat** » Mon Sep 08, 2003 9:16 am

hey thanks guys!

well I have no problem buying things that I dont need at 7psi that I WILL need later on with more boost. I do plan on building the engine when I get the money, so I'd rather not have to re-buy anything that I bought specifically for a 7psi application.

So far based on what you guys have said and what I read, my setup is looking like:

Walbaro Pump370cc SR injectors (these will fit just fine?)S-AFC (cant afford standalone, this is good)RRFPR?? <---- still not sure about this... some say it's needed, some say it's not. I think I might still go with it though since I plan on building even farther than 7psi. What brands do you guys reccomend?

Post by **Red Lightning** » Mon Sep 08, 2003 9:16 am

If you want to buy things that supports more boost, you should look into S15 480CC injectors, SAFC, and a BTM. With 480cc injectors you definitely don't need RRFPR (FMU), just drop in the injectors and tune with SAFC(fuel) and BTM(timing).

Post by **Structure240sx** » Mon Sep 08, 2003 9:16 am

if u really dont want to have to buy extra stuff later when the engine is fully built then get 740cc injectors with a jwt retuned ECU and thast all you need for fuel. get 6 heat range plugs before your built and gap them to .030. then 7 heat range whne ur fully built and turn up the boost more.

Post by **fiznat** » Mon Sep 08, 2003 9:16 am

is the S-AFC a replacement for the JWT ECU or hacked MAFS, or are they different things? I thought the S-AFC kinda did it all, and it's a little better than the JWT ECU cause I can just change the map points when I upgrade -- instead of having to get the ECU burnt again...

Post by **Structure240sx** » Mon Sep 08, 2003 9:16 am

the SAFC can trim down injectors 50%. so will be able to tune 550cc injectors but may be jsut a lil rich. the safc does not tune timing but there are other things that can. im goin with jwt ecu because im goin with 740cc inectors and i dont know anything about real tuning so i dont want to screw it up over a couple hundred dollars

Post by **:: orion ::** » Mon Sep 08, 2003 9:16 am

fiznat wrote:is the S-AFC a replacement for the JWT ECU or hacked MAFS, or are they different things? I thought the S-AFC kinda did it all, and it's a little better than the JWT ECU...

Nope.

Hacked MAF and S-AFC only allow you to run larger injectors on a stock ECU. That's it.

But that only addreses 1/2 the tuning - You need timing control.

It's been proven that for less than 250rwhp (Say 8psi from a T3/T4) you can get away with retarding the base timing a little and be fine.

But for over that power level, YOU WILL BLOW THINGS UP without proper timing control. It could be JWT, MSD Ignition box with a timing retard module (BTM), or standalone (even piggyback standalone like the GReddy E-manage).

Later - Brian

Post by **cosmo** » Mon Sep 08, 2003 9:16 am

not to thread jack but, I'm an idiot

what if I got some 550's, E-Manage and a Fuel pump, would I need anything else?

Post by **fiznat** » Mon Sep 08, 2003 9:16 am

:: orion :: wrote:But for over that power level, YOU WILL BLOW THINGS UP without proper timing control. It could be JWT, MSD Ignition box with a timing retard module (BTM), or standalone (even piggyback standalone like the GReddy E-manage).

That MSD Ignition setup- do you HAVE to have the MSD Ignition box, or can you just use the BTM that is designed to run on stock ignition amplifiers?

I'm talking about one like this:

http://re-racing.com/Merchant2...-5462

Post by **I am Technoman** » Mon Sep 08, 2003 9:16 am

cosmo wrote:not to thread jack but, I'm an idiot

what if I got some 550's, E-Manage and a Fuel pump, would I need anything else?

The e manage timing harness.

Post by **cosmo** » Mon Sep 08, 2003 9:16 am

that's it? no FPR? No nothing else?

Post by **SloS13** » Mon Sep 08, 2003 9:16 am

Ive only been boosted for 100 miles or less, but here's what im running at the moment

walbro 255TT fuel filter (VERY optional)s-afc IIsilvia 370'scrane igniton with BTM

thats it. Later on tonite, im tuning it, i expect to see gobs more power

Post by **fiznat** » Mon Sep 08, 2003 9:16 am

but what about using the stock ignition BTM?? anyone know?

Post by **SloS13** » Mon Sep 08, 2003 9:16 am

stock ignition with btm should be fine. im happen to be selling one on ebay. i dont think the buyer is going to pay up. Its used and i havent tested it, so there's no guarantees it'll work

Post by **Structure240sx** » Mon Sep 08, 2003 9:16 am

depends on how much boost u want to run. at 10pis it was blowing out the spark on my car with stock igniton retard a couple degrees. i put in 6 heat range plugs gapped at .035 (should have gone .030) and it was fine. after that i would look seriously into something amplify spark.

Post by **Structure240sx** » Mon Sep 08, 2003 9:16 am

although 95 240sx, rick, is useing stock ignition and running 16psi with 7 heat range plugs gapped to .020 at high boost

Post by **cosmo** » Mon Sep 08, 2003 9:16 am

SloS13-how much boost do you run? any problems?

Post by **SloS13** » Mon Sep 08, 2003 9:16 am

ive only been boosted for <100 miles. Im running 8psi. By tomorrow, I'll have exhaust and intercooler done

Post by **cosmo** » Mon Sep 08, 2003 9:16 am

sounds good

Post by **andrave** » Mon Sep 08, 2003 9:16 am

hey I just wanted to tell everyone that I'm a bit of a newb when it comes to kaT's but I found this particularly helpful.

Post by **fiznat** » Mon Sep 08, 2003 9:16 am

I did too man, and I'm only 50% newb. Thanks everyone that helped!

Post by **aleph1** » Mon Sep 08, 2003 9:16 am

Ya this is a good thread. It cleared up the whole SAFC w/o RRFPR and info about BTM...One question, which I believe I know, but just in case-the SAFC can tune for a Z32 MAF, correct?

So instead of a JWT ecu or standalone, you could just get:

SAFC2larger injectors (S15 ones are hard to find...)walbro fuel pumpSome ignition box with BTMZ32 MAF

and youd be set?

Post by **SloS13** » Mon Sep 08, 2003 9:16 am

im running stock MAF right now. no problems. only goes up to like 70% on 7psi

Post by **aleph1** » Mon Sep 08, 2003 9:16 am

Really? Ive been hearin people with only like 6-7psi sayin that its at like 99.3% and such....

Post by **fiznat** » Mon Sep 08, 2003 9:16 am

aleph1 wrote:So instead of a JWT ecu or standalone, you could just get:

SAFC2larger injectors (S15 ones are hard to find...)walbro fuel pumpSome ignition box with BTMZ32 MAF

and youd be set?

er I hope not... cause if that's right, then I've STILL got it wrong.

I beleive the S-AFC tunes the output of the MAFS before it gets to the ECU... that way you can run a stock MAFS because the signal it sends is modified by the S-AFC anyways. Somebody please correct me if I'm wrong....

Post by **aleph1** » Mon Sep 08, 2003 9:16 am

I suppose so, but the Z32 mafs is much bigger....

engine/fuel management for KA-T

engine/fuel management for KA-T

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