13.5 AFR`s on WOT

Davie Houston

Davie Houston

Member
Was at the rollers the day to get my SAFC tinkered with and AFR`s just wouldnt come down any lower, so needless to say the set up was aborted, till i get some bigger injectors fitted to it.

Car spec is basically, a fully forged bottom end, ported and flowed head, HKS 264 cams, and running a Turbo dynamics T28 roller bearing turbo @ 1 BAR, and actuator is set to a BAR aswell, also running a Z32 MAF aswell.

So hopefully once the bigger injectors are fitted this will bring the AFR`s down and hopefully let it get a better set up on it.

I know the SAFC isnt the best but am on the case of a Nistune Board :)
 
Trip

Trip

New Member
I am running on standard injectors and MAF, with a GT2871R turbo at 1bar and my AFR's are on the rich side. I am currently using a Field ECU. Datascan is showing me above 100% duty cycle but my datalogger is showing AFR in the 11.



Could it be the Z32 MAF is sending a low value to the ECU since its bigger then a standard MAF ? Low MAF value = low injector duty cycle
 
Davie Houston

Davie Houston

Member
Car has a 255 walbro and fuel pressure is at 3 bar with the vacuum pipe off it.
Possibly could be my maf, as its sat for a while when car was in bits.
Also ECU is free from fault codes too.
 
PobodY

PobodY

Moderators
Staff member
That's very odd - I'm standard just about everything at at 1 bar my fuelling is spot on...
Why would you need the Z32 or bigger injectors to run 1 bar of boost?
 
PobodY

PobodY

Moderators
Staff member
Sorry Stu... I didn't think roller bearings made much difference to the amount it spooled, just how quickly it spooled. I'd understand if it was a 3071 or something. My bad.
 
campbellju

campbellju

Moderators
Staff member
Are you running a dedicated power feed to the fuel pump. If your fuel pump voltage drops then it will flow less fuel. Your injectors could open as much as they like but if the fuel isn't there it won't make any difference. Is your T28 a 2871 or a 2860? A 2871 could feasibly max out std injectors at 1 bar but a 2860 is unlikely.
 
watoga

watoga

Member
Trip said:
How does the ECU know you are using a Z32 MAF instead of the standard one ?
Click to expand...
+1

The injection multiplier which your ECU uses to determine the injector pulse width will be different for a Z32. NIStune can sort this, but I doubt a SAFC can?

Dave
 
PobodY

PobodY

Moderators
Staff member
campbellju said:
A 2871 could feasibly max out std injectors at 1 bar but a 2860 is unlikely.
Click to expand...
That's the bit I didn't understand... although now that I think about it the "28" is the turbine side and the 60 (or 71) is the compressor side isn't it? - It makes sense that a larger compressor wheel moves a larger volume of air at the same pressure. :doh:
 
M

MarkTurbo

Well-Known Member
watoga said:
The injection multiplier which your ECU uses to determine the injector pulse width will be different for a Z32. NIStune can sort this, but I doubt a SAFC can?
Click to expand...
An safc will run a Z32, you just need to change the maf input/output voltage settings in the setup menu ;-)
 
johnsy

johnsy

Active Member
forgive me for the question im about to ask ,

Wot does a fully forged bottom end consist of??
 
stumo

stumo

Active Member
johnsy said:
forgive me for the question im about to ask ,

Wot does a fully forged bottom end consist of??
Click to expand...
it just consists of forged pistons.

I can only guess that fully forged must mean all the pistons they fitted are forged! :der:
 
Davie Houston

Davie Houston

Member
Cheers for the input lads, Fuel pump already has its own dedicated 12v supply off the battery.

The turbo is basically same spec as a 2871r turbo, and was only at 1 bar to start with, to give us a ball park figure before it was turned up.
Also the actuator on the turbo is set to 1 bar.

Using an SAFC to convert the signal from the Z32 to the standard ecu, and settings are spot on for a z32.

So either i have a guffer FPR (standard one) but it holds 3 BAR of pressure all day long, or the Z32 is guffed.
I beleive the safc is fine, as when it was adjusted you could see the afr`s coming down and up depending on which way you done it.
Have ordered a brand new Z32 Maf, as the one i had, i oppend it up, and low and behold its a faker.

SO hopefully that resolves the problem and fit the evo injectors aswell, then all should be happy hopefully.
And my EGT`s hopefully come down as they rocket when you have half throttle to under 1600 F, but ideally they should be about 1400 F/800 C.

So just a waiting game now, on the bits coming and trying to get a rolling road booked and get set up :)
 
campbellju

campbellju

Moderators
Staff member
Are the injectors at 100% duty cycle then? Apart from the FPR it all sounds good. Even if the MAF was wrong you could map round most signals the MAF would put out.

Another basic check is change your fuel filter in case its blocked. Probably not but you never know.
 
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