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Discussion Starter · #1 ·
My friend has a SC300 and bought a front clip from a soarer and swapped in the 1JZGTE.

he has fuel cut at 15psi, but he would like a couple more psi.

I noticed that this engine does not use a mass airflow meter... it just runs a MAP sensor and AIT. So, if he installed a Fuel Cut Defencer in this thing... I am assuming it would just blow his engine... because the ECU needs a correct MAP sensor reading for the fuel injection... if you were to put a FCD in this thing to cap off the MAP voltage, it wouldnt see the extra boost beyond that point and it would go super lean.

What do you guys do when you want to exceed 15 psi without getting all crazy with a standalone or something?
 

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We use FCD's. I used one til i got a SARD ecu with the fuel cut and mph cut programmed out.

Before you turn up the boost to anything over then 15psi, i hope u have 3in DP and exhaust at least, and a FMIC. If things are not optimal expect to blow em.
 

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Discussion Starter · #4 ·
if you installed a FCD, which in effect puts a voltage cap on the MAP sensor... now your ECU does not see actuall boost pressure. So when your boost is at 18psi but your ECU is only allowed to see 14psi because of the FCD, I would imagine its going to blow up either way.
 

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1JZ map is a 2 bar map. -1 and +1. At WOT, the engine uses pre-programmed maps for fuel/air. Welcome to OBD1.
At 20psi, my car runs the same a/f as it did at 15psi says the wideband. Rich.

/close thread.
 

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Discussion Starter · #6 ·
EDIT:

So... if its a 1 bar map sensor, how is it going to know when the car is boosting 17 psi and inject the proper ammount of fuel? A preprogrammed map for fuel injection REQUIRES some type of load measurement. If its not the MAP sensor beyond 1 bar boost, then what is it?
 

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Discussion Starter · #8 ·
you have a SARD ECU that probably has a raised or eliminated fuel cut

there is something missing here. you have to understand how a fuel injection system works to understand why I am questioning how this combination is supposed to safely function.
 

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Discussion Starter · #9 ·
anyone around know what they are talking about on this topic here?

VJ RC: Why do you say that graph you just posted is 20 psi, when you have another thread running where you say that is 15 psi.... wtf ?!
 

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i'm the guy with the ijz sc, lol.

hi. :fruit:

anyways, i'd also like to know, cuz i read that other thread also, and you said it was one 10psi and one 15psi. plus you should be making more than 303 at 20 psi! :1poke:
 

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This is very simple..... Put in the FCD and a SAFC2 and you are set. PERIOD!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

If someone isdumb enough to just put on the FCD and raise boost 4-5psi, yes they probably will experience some mechanical failures. If you put in the fcd and a safc2 you will simply tune in more fuel for the car at the higher boost level. I ran 26psi through a HKS T51s with no more than a fcd and a safc2. That motor lasted for almost two years and I beat the hell out of it. Thats the answer plain and simple.

Side note:" I have an almost brand new HKS FCD I'll sell for 75.00 plus shipping, has 2hrs of use on it, guaranteed to work.
 

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Discussion Starter · #13 ·
no use for a FCD combo in this situation. The proper fix here would be a emanage with the MAP sensor option. The emanage has a built in adjustable MAP sensor voltage cap which emulates a FCD then it can use its own MAP sensor for enrichment starting where the stock ECU left off.

a SAFC 2 is a POS and belongs only in Hondas, as it is does not have a MAP axis... tuning a turbo car with TPS as your only load is a fuckin hack. The same cash for a FCD and a SAFC 2 will pick up a emanage and then it can properly be tuned and with greater resolution and without having to look at a little ricer screen.

:) :)
 

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Oh excuse the shit out of me, I thought you were the one who came looking for an answer...... As for the SAFC2 being a hunk of shit....... Get bent and go enjoy your emanage, but let me know when you make 550 rwhp on that emanage of yours, but then again what would I know, since I am a hack :1poke:

Seriously wtf???

If you wanna change the question to: what would be the best way to tune my car? then the answer may involve the emanage ( I doubt it though) the answer would be a standalone not a piggyback. But in no way would I call someone a hack for using one. :rolleyes:
Welcome to the board though,
Catto
 

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phunk said:
What do you guys do when you want to exceed 15 psi without getting all crazy with a standalone or something?

FCD with a SAFC2 in case you missed it the first time. :)
 

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safc2/emanage is all you need.. no fcd.. tune the car.. you shouldn't need a fcd.. if you encounter fuel cut, you need more injector... teh ecu runs rich, you can tune it out and get a little more then 14 psi.. BUT YOU NEED TO TUNE. beyond 14psi the ecu doesn't know how much air is comming in.. as soon as you hit fuel cut your out of fuel (fuel cut is pretty high injector duty.. probably 90%)
 

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the emanage is only a temp fix while i save enough money for the fuel system, single conversion, f-con, and built trans. i just wanna get a little more out of my stock twins this year. i don't plan on keeping it forever, but it will be a good way to get a little more power out of my stock twins till i do the rest of the work in a year or so.

and i wouldn't jump down phunks throat. he asked a simple question, because everyone and their mother was saying to use a FCD with the 1jz swap and thats that. it took someone who knows more than the common person to realize that about the FCD possibly not working. so, he asked for me. but, i really don't think you want to belittle his knowledge of cars. it would make you look very silly to anyone that knows him.
 

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303whp at 20psi @ 130 degree water temp with the auto tranny, sounds good to me!!

Lets see you hit over 300whp.. Its not as easy as it sounds coach.

I raced someone in town twice (auto 1jz sc300), when i was running 270whp... beat him twice. And he runs [email protected]

At 311whp, i roll race and cream mid hi 12sec cars that trap 110+. Peak HP is just a number, its not everything.

I could hit 350+ easy, with aftermarket cams.....

When i was dynoing 250whp, i was running mid 14s @ 100mph and had to stop going due to loss of traction (2.5 60fts). I havnt been back due to no LSD.

A simple modded car, exhaust, and 1 bar, at least in the automatic 1jz sc300 world, is an instant mid 13sec car. Thats not even 300whp. Stop reading superstreet. The 1JZ with an auto tranny setup right has a HUGE powerband.

People claiming 350+whp and running low 13s high 12s are either 5spd, or cant drive. We thought that kids low 13sec 1JZ sc300 had at least 340whp (never dynoed), only to learn i dynoed 275 on stock boost, what i raced him at) and pulled hard. Stop reading magazines, crazy forum claims... and goto the track and drive. My car runs insaine, can u say that about yours?
 

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phunk said:
you have a SARD ECU that probably has a raised or eliminated fuel cut

there is something missing here. you have to understand how a fuel injection system works to understand why I am questioning how this combination is supposed to safely function.
Phunk, the FCD merely caps the voltage and the ECU will use its 14 psi map for anything above. Since the stock ECU seems to run very rich, there will be enough fuel for a few more PSI before heading above the mid 12s AFR. The other thing that most probably don't grasp, is that you're also running the same timing map for 14 psi. As a rule of thumb, you want about a degree to a degree & a half for every psi increase, in a non-linear fashion the higher you run. So 4 more psi above 14, and you're leaning out, plus you're 4-6 degrees more advanced than you *safely* should be. Add some bad gas, or an excessively hot day, and pop.

Being a FC/FD RX-7 guy, we call those FCDs "fuel cut destroyers" cause they pop apex seals if you use them unwisely. The 1JZ & 2JZ are much more stout but in my humble opinion, get yourself some flavor of standalone if you want rock-solid fuel & timing compensation above 14 psi.
 
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