Safe boost levels for KA-T w/ stock fuel delivery

[koenig]

OK thnx. Well on a side note will an a/f gauge in the car be accurate enough to watch and if it goes too lean get out of boost. I wouldnt be using this for tuning due to its lack of accuracy.

[Import_Ant]

OK thnx. Well on a side note will an a/f gauge in the car be accurate enough to watch and if it goes too lean get out of boost. I wouldnt be using this for tuning due to its lack of accuracy.

imho I wouldn't waste money on it. a pyrometer would be a more desireable gauge and they typically aren't much more than a cheap a/f gauge.

[koenig]

Hmmm well that tells me ehaust temp but the thing is how would i know when its running lean or when its running rich accurely just by the temp?

[Import_Ant]

Hmmm well that tells me ehaust temp but the thing is how would i know when its running lean or when its running rich accurely just by the temp?

indirectly, if you are running lean it will run hotter. The pyrometer is a good gauge to tell if your exhaust is running too hot and will act as a warning of when you should shut things down. part of why you run into problems running lean is you run the exhaust too hot past your motor's tolerances.

personally I will be tuning using a pyrometer in conjunction w/ a wideband. if you just want to have something as a 'warning' as far as when your motor is in danger it is alot better of a choice and actually gives you factual info as far as how hot your exhaust is running.

(btw 900 degrees celcius is about where you want to be. anything a 1200~ and above and you'll be melting pistons)

[:: orion ::]

People say you can, but timing affects EGT more than A/F...

You CANNOT tune accurately with an EGT gauge UNLESS you have smethign to give you real-time ignition timing readings, on the fly.

Otherwise, it's a worthless gauge.

By the time it tells you something useful, your KA-T is DEAD.

...

DSM guys swear by EGT gauges b/c their ECU can actively pull timing whent hey sense knock...Nissan ECUs see knock and pull 8 degrees in one shot...no more, no less...and the knock sensor is ignored by the ECU above the torque peak. So knock at 5500 and say goodbye motor, then watch your EGT gauge read too high (too late).

FYI...

- Brian

[Import_Ant]

Of course. I wasn't advocating tuning with it ALONE. it is a good indicator of your tuning based off of what CONSISTANT EGT's you are running. if you are regularly getting high EGT readings above 900-1000 degrees celcius something is wrong and should be looked into, but by no means should it be used for real-time tuning.

[WDRacing]

lots of misinformation in this damn thread.

A SAFCII is a perfectly fine tool to use for tuning. The problem with the SAFCII only as a source of tuning is you have no way to retard your timing on boost. Which becomes imperative over 8-9 psi, especially on a hot day. I run 15 psi with 42 lb injectors tuned via SAFCII and have it set perfect.

There are so many people running 370's with a SAFCII, you can basically copy the settings they have and you'll be fine. Run slightly richer is your worried.

If you don't have factual information to post, then don't post anything. This isn't a matter of opinions, it's about what works and what doesn't. Alot of newer younger members read this and I don't want anyone getting confused with all the damn BS.

WD

[koenig]

I would be running the upgraded fuel pump. I would never boost without that atleast. I am just maming sure that other people have been ok with just the fuel pump temperaraly or in your case for a while. Thnx for the info. So u like how the kit hauls and performs as a daily driver?

[wannawangan]

270cc (stock) + FMU (8:1) + upgraded fuel pump (i.e. Walboro)

Is this pretty much the bare minimum I need to be able to boost up to 8psi on the stock KA24DE?

Just need to further clarify required fuel system upgrades w/o the use of upgraded fuel injectors + aftermarket A/F controller (i.e. Greddy eManage, ApexI S-AFC II, etc.)

BTW - Thank you to ALL those who have contributed to this thread.

[Florida240sx]

260cc is stock..Also what I've read all the a/f gauges are worthless unless it's wideband correct??I'm hooking up my safc and tuning slightly.Once I get my MBC I'm going to a dyno to hook up to a wideband...I see it as pointless to have a gauge, however if you get abd tank of gas you may catch but usually you won't notice anywayz unless you have a warning gauge.WD or Fiz please back me up on this..This is what I have come to understand, if I'm wrong let me know.WD are you no longer running the btm??Although is that 15psi with your water injection?I want to run 12-15psi....Got the SAFC II I have the option of 36lb or 53lb injectors. 370cc sr's and tomei 555cc. Although plan to use 370cc in my SC vert...Figure running a little rich turboed won't hurt will it?because 555/260 is a little bit more than recommended.

[WDRacing]

I have the BTM yes, I also have a alky/water injection kit in work. Well I have an alky kit, I'm just making it better.

The BTM is the way to go. I also have a MSD Knock meter. Which is a GREAT thing to have. If you can actually hear the detonation inside the motor, it's doing damage. The knock meter picks it up WAY earlier and is adjustable. Tuning for power means tweaking alot of stuff from timing to fuel maps at peak torque and there after. The knock meter lets you know when you gone a tad lean or to much timing retard/advance has been done.

WD

[Florida240sx]

So if I'm going to bump my boost I should get the BTM then...Didn't make your own alky kit? Seems like buying a kit is a little overpriced... The knock meter with the SAFC II is inaccurate correct?What all do I need to use the BTM...read it and seems like I need the ignition and blaster coil?Also there was 2 models of btm.

[Crazyracer77]

Save your pennies and do it right.

[Deadrodent]

where can us turbo-noobs find safc settings? i'm currently building my car for a turbo setup and am trying to figure the kind of setup that would be right for me. (i'm doing suspension and brakes first as this will save my life NOT 250RWHP)

[huguetpj]

^^^ Exactly.

To make it very clear, b/c this thread got a little muddy somewhere...

For a KA-T with:

Stock Injectors ONLY: DO NOT BOOST at all.Stock injectors (270cc, BTW) + FMU: Safe limit of 8psi370cc SR20 injectors + S-AFC: Safe limit of ~240rwhp (7-8psi from a T3/T4)

- Brian

Extending a bit from PERSONAL experience (don't blame me if any motor goes pop). You CAN run 4PSI on stock fuel system, would I recommend it? No. Things start getting really hot in there, but I was using forged pistons so that helped me. I even went up to 9PSI on the dyno with my stock fuel system and got 192WHP.

As some one said... it's best to save up your pennis and do it right the first time... I'm on my third rebuild as we speak to put things in perspective... but I love pushing it a bit further every time.

[hek1620]

wd, i am putting in 550cc inj., safcII, small t3, wideband(should i), and btm. probably knock meter too. i want to run about 8-11lbs on stock internals. how much hp/tq could i make safely?

[Mustangs_Suck]

So do u guys think its safe to run 7-8 psi with only upgraded fuel pump? I will eventually upgrade the fuel system later but funds are short right now.

not at all. Get the SR injectors. they can be had for very cheap. Many sell them in the classified sections - look around for them.

[tryiian]

Hey guys, I don`t understand some things here. For where it`s relevant, i`m planning on using a bare-minimum setup for whatever little kick I can get out of it for cost effective power:t3/04e 50 trim .63 a/r(I wanted to use a t28 but quick spool = too quickly for mileage driving)some average sized fmicsr injtial 38mmSAFCNot sure if a BOV is an essential part of a turbo system or not yet... if so, whatever used bov I can afford, too.

Question #1, How does an safc work?: FMU = fuel management unit, i.e. SAFC? What this does is control the fuel pressure, and through that, how much fuel is going through the stock injectors and pump? Or is an adjustable pump necessary to use the SAFC? Where does an SAFC hook up to to control the fuel flow, the ecu?

Q2 necessity of Inj/FMU/RRR/FPR?: For 8psi max, (my planned weekend boost, on an all stock engine) I was planning on running sr injectors and an SAFC. Would that flow the right amount of fuel? Do I need the adjustable pump anyway or instead of the injectors or both?

Q3 Do I need a wideband+dyno tune for saftey?: I hadn`t planned on getting extensive tuning, due to expense, I was gonna take whatever I got out of SAFC tuning and retarding base timing if necessary. What on my car would be tuned if I was to take it to a dyno and have someone who knows what they`re looking for adjust things by getting wideband readings? Would this tuning be necessary for the safety of the engine or just to increase power?

Timing management Q: Not fuel related but, for 8 psi, will I need any form of timing control, like the BTM or emanage? Also, I`m not up to date on all my turbo info (like I needed to say that after exemplifying through all these questions) so can boost level be controlled by something mechanical/hardware related on the external wastegate (like the tial 38 that everyone uses)? Or do I need something that controls boost "electronically"? I`m likely not using an MBC after reading about reliability problems with them.

Safety monitoring q: I understand how the EGT would be a good way of figuring out the average condition of your a/f and seeing a problem that way and how because it would be gradually affected by changes in afr that could happen quickly in the engine, so what would the best (affordable) method of monitoring the AFR be? Is a narrowband a/f system the same as any "a/f gauge"? and doesn`t the safc monitor knock in realtime? Wouldn`t that be all that I need to monitor how my KAT is doing?

I know I`m probably being selfish by askin for so much in depth explanation but even in all the threads and writeups I read, it`s still very difficult to get an explanation to every question I have, and answering this stuff would likely help a lot of people who are in a similar situation of ignorance as me.

[dj_hype]

Yes, a BOV is very essential. Without it, you will have compresser surge and possibly even backspin. Don't be cheap and get a good bov.

A1: SAFC is a piggy back fuel computer. It takes the air readings from the sensors and tricks the ecu into dumping more fuel. An adjustable pump isn't needed. A walbro 255 is perfect and they are $99 shipped brand new on ebay. The SAFC splices into your factory harness inside the cabin.

A2: SR's and SAFC are perfect for 8psi as long as you have it tuned correctly. Dyno tune it and have them use their tail pipe sniffer or buy a wideband.

A3: For safety, definetly. There are tons of threads on the base settings for the SAFC with SR injectors. But every engine is different. You need to dyno/wideband tune the motor for absoulute safety:maximum horsepower.

Timing A: For safety, yes. For getting this thing up and running for the cheapest possible, no. I have a BTM but I had originally planned on boosting 6psi with a FMU but am changing my mind. I'm selling the FMU and getting SAFC/370's. I will be using a MBC and know many people who do and none of them have ever had any problems with them. But, it's up to you.

Safety Monitoring A: Forget EGT unless you can monitor timing on the fly. You have to understand that motors don't like to run lean. It only takes a split second to go from perfect AFR to detonation and having to swap in another KA. Forget an "A/F Gauge" from Autozone, those read from a crap narrowband o2 sensor and don't mean jack **** on a turbo's motor. You need a wideband sensor with a wideband o2 gauge to actively monitor the safety. But if you go to a dyno and have it tuned and set up perfectly, as long as you don't change anything, you won't have anything to worry about. As far as SAFC monitoring knock in real time, i haven't heard of it but it doesn't mean that it doesn't.

hope this helped.

[dj_hype]

Just to correct something in my previous post, I just read that the SAFC II has an integrated knock monitor so, it seems it can help a little there.

[tryiian]

Absolutely lovely. Thank you!

[jae_rex]

So will RC 440's sidefeed from Civic work on a KA rail? This would be helpful. I got the 440's for free.

[S13FX]

Is it a DE or a E?

[jae_rex]

It is an "E"..thanks in advance

[S13FX]

no they wont because the KAE injectors are top feed. But Im pretty sure you can trade those in for some top feed in jectors .

[my91silvia]

Quick question because i am in the same situation. What does FMU stand for?

[sunnys14]

FMU - fuel management unit?

[babowc]

i have a real stupid question..but lets say you tuned the car and had to change your battery out....

would the settings in the SAFC reset?as it seems like things eleswhere in the car resets..

[Jookmasta]

no it wont reset.................happens to me all the time as my battery dies after the car sits for about 2 weeks.........

[babowc]

ooh okay.thanks for clearing that up for me