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300zx Tt - Apexi Safc Ii Help Me!!
- Thread starter mojo2018
- Start date
Already got the wiring and plumbing sorted (done myself!!! no worries 1/2 a day) Looking for a rolling road with a good reputation that knows the kit I have to be able to adjust it and use it properly.
Car was running 1 bar on bleed offs when i bought it with no fuel mod's, cats out, induction kit and full stainless system. (I'm really scared of melting pistons!! boost now back to 0.7/0.8)
Got any recomendations for a good rolling road????
So far suggestions from my friends have been 'oldam engineering' who set up a friends 'super 7' 'Powerstation' and another local one (haven't spoken to any as yet).
Car was running 1 bar on bleed offs when i bought it with no fuel mod's, cats out, induction kit and full stainless system. (I'm really scared of melting pistons!! boost now back to 0.7/0.8)
Got any recomendations for a good rolling road????
So far suggestions from my friends have been 'oldam engineering' who set up a friends 'super 7' 'Powerstation' and another local one (haven't spoken to any as yet).John Dixon
Well-Known Forum User
SAFC is not a good mod on the Z.
It just tinkers with the MAF signal which affects the timing as well as the fuelling.
Also, it's a 2D mod imposed over the 3D maps which makes no account for engine load so you might get a nice fuel curve at full load on the dyno but then it can be miles off in the mid range.
It just tinkers with the MAF signal which affects the timing as well as the fuelling.
Also, it's a 2D mod imposed over the 3D maps which makes no account for engine load so you might get a nice fuel curve at full load on the dyno but then it can be miles off in the mid range.
Can you not correct the mid range using the high and low throttle corection settings??
Also you are only varying the one input to the ECU not all of those back from the MAF, should the ECU not correct the timing to account for more fuel (more air from maf signal) any way??
Also you are only varying the one input to the ECU not all of those back from the MAF, should the ECU not correct the timing to account for more fuel (more air from maf signal) any way??
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John Dixon
Well-Known Forum User
All you're doing is modding the MAF signal. The ECU uses air flow to calculate theroetical pulsewidth to use as load index on maps. Effectively you fool it into adding more fuel by pushing the reference across the map, but it also moves it to the wrong point on the timing. It can never enrich past the riches point on the map either.
Fair Point
At present all I want to do with it is add and remove small amounts of fuel in the right places to stop the car from running to rich at idle and lean at max boost/load.
Granted I know it won't allow you to go past the standard ecu's mapped maximum but with only a few mods done to the car i.e. exhaust induction and boost controller (running @ 0.9 bar) will it not allow me to alter the map enough to cope with these minor mods now and allow me to fine tune in the future when more money allows me to mod more (i.e fuel rail + injectors cams stainless head gaskets pistons intercoolers fly wheel, clutch, and most importantly different brain).
At present all I want to do with it is add and remove small amounts of fuel in the right places to stop the car from running to rich at idle and lean at max boost/load.
Granted I know it won't allow you to go past the standard ecu's mapped maximum but with only a few mods done to the car i.e. exhaust induction and boost controller (running @ 0.9 bar) will it not allow me to alter the map enough to cope with these minor mods now and allow me to fine tune in the future when more money allows me to mod more (i.e fuel rail + injectors cams stainless head gaskets pistons intercoolers fly wheel, clutch, and most importantly different brain).
John Dixon
Well-Known Forum User
It'll never allow you to adjust for different injectors, or it might but timing will be miles off.
You're better just having the ECU remapped to start with (or just chipped for you minor mods).
To some degree you will be able to do what you want at the moment but its a crude and nasty way of doing it. Stock nissan maps are usually pretty rich at max boost anyway, you sure you don't have a separate fuelling issue?
You're better just having the ECU remapped to start with (or just chipped for you minor mods).
To some degree you will be able to do what you want at the moment but its a crude and nasty way of doing it. Stock nissan maps are usually pretty rich at max boost anyway, you sure you don't have a separate fuelling issue?
maybe?/
At Idle the car is stinking of unburnt fuel, (i.e too rich) and at 1.0 bar on a really hot day when its been thrashed a bit it has in the past pinked. But never badly enough to worry me, I've always just lifted my foot out of it pulled over and turned the boost down. It is a UK car and I only run it on Optimax. And it has not done that for years now.
Not so long back I was thinking that maybe I had a dodgy EGR valve and or AIV's but having checked they seem to be working fine.
Any suggestions???
At Idle the car is stinking of unburnt fuel, (i.e too rich) and at 1.0 bar on a really hot day when its been thrashed a bit it has in the past pinked. But never badly enough to worry me, I've always just lifted my foot out of it pulled over and turned the boost down. It is a UK car and I only run it on Optimax. And it has not done that for years now.
Not so long back I was thinking that maybe I had a dodgy EGR valve and or AIV's but having checked they seem to be working fine.
Any suggestions???
John Dixon
Well-Known Forum User
Stuck fuel pressure reg? Causes high pressure on idle and low on boost.
Same goes for bad PRVR system. Try bypassing it by connecting FPR vacuum line straight to the plenum.
Where in UK are you, could look it over for you.
Same goes for bad PRVR system. Try bypassing it by connecting FPR vacuum line straight to the plenum.
Where in UK are you, could look it over for you.
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fpr
Do you mean to bypass the solenoid which controls the fuel pressure reg?? and go straight line between the reg and engine side of butterfly??
If so what is the point of the solenoid???
Would you disconnect the solenoid as well as bypass it??
Also the car is being a pig at the moment, Cranking over and over about 15 seconds before starting after a long run. Checked and replaced most of the sensors now so am fairly sure it is not any of that now, thinking maybe fuel pressure may cause this as well??
I'm In Bristol, but the car is in Gloucester.
Do you mean to bypass the solenoid which controls the fuel pressure reg?? and go straight line between the reg and engine side of butterfly??
If so what is the point of the solenoid???
Would you disconnect the solenoid as well as bypass it??
Also the car is being a pig at the moment, Cranking over and over about 15 seconds before starting after a long run. Checked and replaced most of the sensors now so am fairly sure it is not any of that now, thinking maybe fuel pressure may cause this as well??
I'm In Bristol, but the car is in Gloucester.
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John Dixon
Well-Known Forum User
Yes, connect as you said.
The solenoid switches the reg vacuum signal between a cannister held at full boost pressure via a one way valve and the plenum. Cannister is used for starting and for very high fuel temps. It's not required in this climate. The problem is that the cannister can split leading to no boost being seen by the pressure reg.
If you bypass it you can disconnect the solenoid and bin the cannister / valve if you want to.
Starting prob could be fuel pressure although unlikely. Also, one way valve in fuel pump can fail so you have to re-fill the system when you start.
I'm only in kidderminster, about 45mins from Glous if you want to run it over some time.
The solenoid switches the reg vacuum signal between a cannister held at full boost pressure via a one way valve and the plenum. Cannister is used for starting and for very high fuel temps. It's not required in this climate. The problem is that the cannister can split leading to no boost being seen by the pressure reg.
If you bypass it you can disconnect the solenoid and bin the cannister / valve if you want to.
Starting prob could be fuel pressure although unlikely. Also, one way valve in fuel pump can fail so you have to re-fill the system when you start.
I'm only in kidderminster, about 45mins from Glous if you want to run it over some time.