Have I maxxed out the 044 pump?

[V8hilux]

Here's a quick listen with the old tune just after I was installing the engine back into the car after cam/head/turbo upgrades.

http://youtu.be/HieaWTJiGLo

(tried to embed the you tube vid but dont know how?]

[vlad01]

haha yeah. i see people have this problem before.

So before I even started tuning I had The1 test my injectors and generate the offset table data.

I'm just about done with the fueling side just after 2 week. Its pretty rock solid fueling wise, tuning is heaps easy when you are not chasing your tail.

[VL400]

I looked over at the other side of the kinjflow spreadsheet and saw "injection pulses per cycle" and it said 2.???

I changed that to 1 because I think I am running single pulse in the flags.

Make sure you are using double fire, and then the auto switching function for low pulse times to keep idle happy. Setting to single fire with the single/double fire flag is limited to 50% injector duty cycle.

[V8hilux]

So what's the idea of the double fire?

I was thinking i only wanted one long squirt at idle and under boost rather than 2 shorter ones. on single fire watching the moniters it idles at 1.5ms pulse. How does the double fire give more fuel at say, 100% duty cycle? doesn't it have to turn off once per rpm whereas the single can just stay on constantly... hence 100% duty cycle. what am I missing here?

or doesn't 100% duty cycle mean it stays on all the time? perhaps only 100% of 1 revolution of the crank and the double fire can go to 100% on both revolutions in the 4 cycles?

[V8hilux]

also I'm confused about the injector displacement/grams sec table now. Is the cylinder cc/grams per second of 0.073 correct. The kinjflow calculator says "kinjflow of 0.039" which I know is way too low. ?

when in double fire mode... would it give me 2 squirts of the full 0.073constant per rev or do I need to half that number back to 0.039 on double fire in that map?

[V8hilux]

is the kinjflow calculator for ose12p or just stock memcals? should i just use cc/grams second

[VL400]

or doesn't 100% duty cycle mean it stays on all the time? perhaps only 100% of 1 revolution of the crank and the double fire can go to 100% on both revolutions in the 4 cycles?

Exactly. The ecu operates in engine cycles. So say 10ms of fuel is calculated which is for one full cycle, double fire injects 5ms+opening time each revolution. In single fire its 10ms+opening once per cycle but is time limited by a single revolution (this appears to be a hardware limit on '808s). Single fire is useful at low rpm where large injectors mean a tiny PW, splitting a 1.5ms calculated pulse for double fire becomes pretty small! It becomes much more critical to get your opening times correct.

Try double fire and the correct (or just slightlky higher) kinjflow value. Set "Run A/F Param - Minimum BPW for sync double fire fuel delivery (Upper Value)" and "Run A/F Param - Minimum BPW for sync double fire fuel delivery (Min Value)" scalars to around 2.5 and 2 ms respectively. This will switch to single fire at idle at light loads.

[V8hilux]

Try double fire and the correct (or just slightlky higher) kinjflow value.

Which one's the correct value? lol.

0.039 kinjflow figure as per kinjflow spreadsheet, or the 784cc / 10.7grams second? of 0.073

on single fire at idle reading the normal ve table... the idle cells hover around 37ve at idle with the 0.073 constant value. good enough for the bush? at 0.039 the ve's need 50-60ve to idle.

Thanks.

[V8hilux]

I'm trying another alternator on the car now, Last night I was seeing the volts drop from 13.2 down to 12.8 and I was mucking with the voltage compensations to keep a constant afr at idle to match the desired afr. but this morning I started the car when it was cold and also reading in the 12 volt range and it was sooooooo rich the wideband stop'd working. lol. black smoke everywhere... god this is miserable.

It seems I can tune the afr good at high temp and 12.8 volts but then it is too rich when cold with 12.8 volts.... or I can get good afr cold and 12.8 volts and then suffer surging 18afr when hot and 12.8 volts.... AAAAHHHHHHHH all without touching the ve table.

One of those tables is stealing my fuel when hot. Just need to put my finger on which one... it's either the 2 volt tables or that dreaded charge temp inverse temperature term one. Does anyone touch that table or leave it factory?

anyone else seen this or am I just real unlucky? or is this hot arse engine bay un tunable? lol.

I'm heading out to finish the new alternator and upload the double fire.

cheers

[Jayme]

from memory, when you tick single fire, you have to double the kinjflow value to get the same fuelling you had in double fire. always leave single fire unticked and let it choose single fire on its own based on the values VL400 gave you. then use a kinjflow of about 0.044. when you set the minimum BPW values and let it choose single fire on its own, you can use a normal kinjflow value and it sorts the single fire kinjflow bit out automagically.