Give Enough Pressure To Bypass Ecu Protection

[rmahnovetsky]

Hey guys

If I remove my old fuel pump and replace it with the bosch 040, will it provide enough fuel pressure to bypass my ECU protection (rich retard) for up to 14 psi? So basically I'm going to increase the fuel presure and tune it with the safc so I can bypass the ecu protection so I can run higher boost with the rb25det flat spot.

Car: R33

relevent mods, full 3" exhaust, safc, cooler kit

[paulr33]

the rich and retard protection is based of the airflow meter value

[Cubes]

It will be running quite a bit of ign. timing, should work ok.

[rmahnovetsky]

So I'll have to retard it slighty a bit then, you were saying that saying in a previous post of mine.

Bit of a Band-Aid, but if it works I'll be happy for now until I get a real computer.

Well I'll give it a shot and post up some results... Most likely get something up next weekend..

[Cubes]

Its a fine balancing act, but if done carefully I don't see why you can't make good reliable power.

Edited November 13, 2005 by Cubes

[BHDave]

Why crank up the pressure? By doing that, when you tune the safc you will be taking out even more fuel and so the ecu is looking at a lower point in the maps and so it will be running more timing (than if you maintain stock pressure)and will be more likely to ping under load.

[Cubes]

If your having R&R then the only option to try if you really don't want to shell out a few more $$ for a pfc is to crank up fuel pressure and pull out even more volts from the afm, as a result using a lesser load point shooting 'just' under the R&R area of the map.

It is more likely to ping, but if done carefully you can gain more power. If it doesn't ping then your on to something good.

BUT I don't see this usefull for a car with a std turbo as you really don't want to be pushing the turbo past 12psi.

Highflow.. yes it may help.

[JeeTeeEss25Tee]

I have similar mods and dont think SAFC would be good for more than 200kw ( started to ping afterward). Until you have a PFC, just keep the boost to 10 psi. I would hardly hit 12 psi for daily drving.

[rmahnovetsky]

I will be using a dual boost controller, so only 5psi as a daily driver and 13 psi after 4500 rpm.. I will only be using 13psi for less than 14 secs at a time so the turbo should last for a bit.. I pretty confident 13psi should be fine as a my mates VL with rb25det is running 13psi with turbosmart bleed valve and the turbo is still kicking strong after 1yr of heavy daily abuse..

[rmahnovetsky]

well, I have ordered the 040 and hopefully I get it before the weekend.

I hope I can get this tuned with the CAS and the SAFC alone. Hopefully I won't need to get a malpassi or some other rising rate fuel pressure regulator..

[rmahnovetsky]

pump has arrived ...

Has anyone taken the fuel tank lid off? I tried getting this off a while ago. I had to get a hammer and rod to try an move the lid - very tight and ony move 2 cm. Anyone know of an easy way to get it off?

[benl1981]

Umm - problem people have is that when they lean of the mixtures via the SAFC that it pulls it to another load point that adds more ignition advance. If you richen the mixture up by more fuel pressure you are in fact making the case worse!! Like someone else has said. You don't need more fuel pressure unless you have a fuel problem already - they usually run very rich!!

[Tangles]

So, this is VERY interesting....

Ive gone ahead and bought a 040 Bosch fuel pump, and am having high pressure fuel lines installed, along with an Apexi SITC (super ignition timing converter), along with a Nismo fuel pressure adjustable regulator, and along with a Z32 Air Flow Meter (I think thats all!!!). This is happening next Tuesday at Graham West Workshops in SA.

Car already has an Apexi fmic, a Apexi SAFC, a full 3inch exhaust with hiflow cat, a K&N pod filter, yadayadayada....

So, having just read this thread, would it be more helpful then for the original poster to be using this tuned SITC piggyback computer? I was on the thinking that this would be a great thing to do before I hiflow the turbo next year.

My car is an auto and I wont be installing a PFC. The SAFC stays along with the SITC.

Any input or suggestions?

Cheers (sorry to hijack thread, thought it might help both of us mate!).

Brendan

[rmahnovetsky]

Umm - problem people have is that when they lean of the mixtures via the SAFC that it pulls it to another load point that adds more ignition advance.  If you richen the mixture up by more fuel pressure you are in fact making the case worse!! Like someone else has said.  You don't need more fuel pressure unless you have a fuel problem already - they usually run very rich!!

<{POST_SNAPBACK}>

I'm hoping retarding the the timming will help... As I said before I have seen it done and the car is very quick!

[Tangles]

So (paulr33), would a Super Ignition Timing Converter piggyback computer help in this instance, with tuning the SAFC? I think they are +/- 20 degree ignition advance / retard.

Cheers, Brendan

Edited November 17, 2005 by bwilkeson

[benl1981]

Yes you could retard the base timing but then you are retarded at areas that could do with some more advance.

First of all you need the SAFC to change the AFM values so you dont go into rich and retard mode. If you add more fuel pressure than normal you are making it a lot harder for yourself as you will have to retard the timing further = loss of response!!

[paulr33]

it sounds like it would. having not used either and only knowing the basics of both it sounds logical. sydneykid was doing the same setup in his stagea as it was auto as well. the stock ecu rich and protects comes from the airflow meter measuring too high, presumably near 4.5volts ish i would guess ? if you however below this with the safc and the adjust the timing with the sitc then it should be a fairly good comprimise.

[benl1981]

I think its been said the the rich and retard coccurs when there is a sudden change in the AFM levels (i.e quicker increase than it thinks there should be)

[Tangles]

Max AFM is either 5.16 or 5.06 volts (thats what my tuner tells me for the R33 series 2). Mine is at 4.95volts after tuning via SAFC, with 141kw at the 4wheels in my STAGEA.

Thats right, following SK's footsteps. I think the SAFC is tuneable at 7 points in the rev zone, whilst the SITC is tuneable at 5 points in the rpm zone.

My injectors were at 76% duty cycle. Ive gone the adjustable fuel pressure regulator path due to not wanting to put in larger injectors. I figured putting more pressure (up to 10psi more over standard; with high-pressure fuel lines ppls!!) would be a cheaper move than larger injectors.

Thanks Paul & Ben for you comments. At the moment with my fmic install 2 weeks ago I reckon by feel Im in the rich / retard mode........

Hey rmahnovetsky, maybe you should get a SITC too! They are on ebay for around $200US but havent been made for a few years, so most are 2ndhand via Japan (I got one of the last ones brand new for $220).

[benl1981]

I found that an R34 gtt cooler was enough to put mine into rich and retard mode at 9psi. Previously with R33 cooler it was ok.

I hnow have a PFC running 10psi and base map. I am up around 4.91v volts and injectors are at 84%. I'm getting a tune soon though and hope the injector duty cycle will drop a little...as apparently they run rich on the base map. Its not blowing out much smoke though at full throttle.

BK - what boost are you running??