new user a few questions

[ricardomendes]

hi there, i have a s13 with ca18det after the engine rebuilt my intencions was running a stage 3 chip, specs are

- Forged rods and pistons
- ported head
- Exhaust cam on the intake side
- 1,2mm ACL race
- 444cc injectors (now 720cc)
- GT28R s15 spec-r
- z32 maf genuine
- xspower exhaust manifold and 76mm full exhaust
- fmic
- OEM FPR
- walbro 255l/H



i notice that my car with stage 3 chip make a lot of black smoke only running 0.7 bar so i bought the nistune to map my car, with the stage 3 bin in nistune i started to make some logs and i notice the TP scales have the max os 80 and i hit that at 4500rpm and then starts the black smoke and 9:1 afr...

so i make a new bin with more tp scale, and diferents K and latency values to get 14.7 at idle, k=413 and latancy 720, and with 11:8 afr at high revs i max out the 444cc with 0.9b boost. so now i´m using some denso 720cc with latency around 990 and a idle of 14:8.

i notice while mapping, if i turn my z32 Maf my afr will be diferent and richer but my duty and ignition timing are the same and the voltage of MAF is same too, the only thing diferent is the injectors ticking more audible, i notice this with both injectors 444cc and 720cc.

my question is, the Maf change the injection timing and this is why the afr go richer?
i have the maf upside down and i would like to know what is the best position or stock 300zx position.


is there any way to control de AAC valve throw nistune?

with 720cc, every time i step on the gas the afr will richer and then go stable to around target AFR, to have this more smoth i need to ajust the acceleration tps table or min ttp?

great regards


ricardo

[Matt]

What do you mean turn your MAF?

MAF readings affect where your TP (load) cursor is going to be on the timing/fuel maps. So yes if the MAF readings change then the location of your maptrace cursor may be somewhere else giving a different ignition timing value

AAC valve duty cycle is not controllable via Nistune

If your throttle (TPS) is almost full then it will read the last column of the fuel map. I dont believe this ECU has a TPS enrichment trigger table to adjust, so just where it lands in the fuel map

[ricardomendes]

What do you mean turn your MAF?

MAF readings affect where your TP (load) cursor is going to be on the timing/fuel maps. So yes if the MAF readings change then the location of your maptrace cursor may be somewhere else giving a different ignition timing value

i meant to say if i rotate the maf, not invert the flow, in ca18det is easier to put it like this
but i think i need to use it like this


if i turn it for top to bottom it changes my afr, but the maf voltage, tp, ignition, etc is all the same values on nistune, the only thing different is the injectors ticking more audible.

If your throttle (TPS) is almost full then it will read the last column of the fuel map. I dont believe this ECU has a TPS enrichment trigger table to adjust, so just where it lands in the fuel map

i meant to say, you have tps off, then step the throttle and it goes richer for an instant and then it come to target afr, from 3500rpm to 4000rpm i have a target of 12:8 afr but it goes to 11:2 and then 12:6, my question is if i lower the value on the acceleration enrichment table vs tps it will make the transition smoother ? have a log to show if you want

regards

[ricardomendes]

another question, when you redefine your K and latency you do it with vacuum on FPR or without vacuum?

i made mine with vacuum trying to get 14,9 afr at idle, if i change to get 14.7 without vacuum when i connect it the afr goes to 16.1 and the car don´t idle fine, i assumed it will be with vacuum.

what do you guys usually do?


regards

[Matt]

Adjust K with part throttle to get the car running okay and then test the AFRs against the rev range

Idle AFRs can be changed with latency if required. There is no difference in enrichment between idle/off idle with these ECUs (only timing)

Probably logs for the other issues would be helpful. I wouldnt see how repositioning the location of the MAF could affect things too much apart from perhaps heat in the airflow from the radiator

[Matt]

Adjust K with part throttle to get the car running okay and then test the AFRs against the rev range

Idle AFRs can be changed with latency if required. There is no difference in enrichment between idle/off idle with these ECUs (only timing)

Probably logs for the other issues would be helpful. I wouldnt see how repositioning the location of the MAF could affect things too much apart from perhaps heat in the airflow from the radiator