Nissan ECU Tuning

Mr Fast · Joined: 16 Nov 2003 Posts: 98

is there anybody that has a good working 850cc bin,
im running one now but i have idle problems, from 2000rpm the car runns great under 2000 rpm the engine often stop and drop below the idle setting.

i just need to see the latency k-value ++ the basic setup, just to be sure this is correct , fuel and timing is not important.
the car is running on 300degree rails with sard 850cc injectors.
fuel pressure is set to 4 bar.

my email is: ottoolsen@alten.no

Performance_Addict · Joined: 29 Nov 2007 Posts: 10

Here are two:

850cc Dual Intake Base map
http://www.fast-files.com/getfile.aspx?file=16828

850cc Single Intake Base map
http://www.fast-files.com/getfile.aspx?file=16829

Mr Fast · Joined: 16 Nov 2003 Posts: 98

Thanks but this two files i have, they are not very good

is there another file out there?

Otto

Eric · Joined: 17 Nov 2003 Posts: 258 Location: Holland

what Sard injectors are you using exactly ? for the latency values as recommended by Sard look here:

http://www.sardracing.com/products/Injectors.htm

for true 850cc injectors (are you sure it's not the 800cc sard ones?)
the K-value should be around 146

-Eric
_________________

DTA-motorsport

Mr Fast · Joined: 16 Nov 2003 Posts: 98

Mr Fast · Joined: 16 Nov 2003 Posts: 98

Eric · Joined: 17 Nov 2003 Posts: 258 Location: Holland

>> the fuelpressure is 4 bar

I think there's your main "problem"
the race cams obviously also have an influence on the idle...

the 850cc is rated at 3 bar
at 4 bar they probably flow around 990 cc and the latency time is influenced by an unknown percentage.

Any reason you have set the pressure to 4 bar ?
does you car have over 850 hp ?

if you absolutely need to have it at 4 bar, then best is to have the injectors flow tested at 4 bar to see how much they flow exactly and if all injectors flow the same amount.
Also important is that your fuelpump is able to keep the pressure up to 4 bar all the time, all across the rev range and under full boost.

if one of these variables fails, it has absolutely no use to have the fuelpressure at 4 bar and you should set it back to 3 bar and (fine) tune from there..

-Eric
_________________

DTA-motorsport

Mr Fast · Joined: 16 Nov 2003 Posts: 98

Hi Eric!!

the reason the pressure is adjustet to 4 bar is that the engine is somwhere around 850 to 950 hp, and the biggest injector set is 850cc, its possible to get bigger, but this needs a custom order and takes time.
The fuel system is ok, to pumps flowing total 360 l\hour, 12mm tubing and,
parralell connection to the rails, new hi flow fuel filter, and sard race regulator. the latency is best at 85 dec k-value is set to 252 (dual filter setup) i use nistune to map, and this setup seems to work best.
i have retarded the cams a little, and the idle is mutch better.
the problem thats left, is when im reving the engine, it dont stabilice at 1000 rpm it drop below and stops, if i do this slowley its ok the engine runs at 1000 rpm, the TTP min is at stock settings i have tried to adjust both up and down without any luck, do you know whats the propper settings for the TTP min with the new injectors.

Otto

nzniggles · Joined: 26 Aug 2006 Posts: 64 Location: New Zealand

If you are running a dual MAF set up, have you installed the idle stabalisation pipe?
Have you checked that the idle control solenoid is not sticking?

Mr Fast · Joined: 16 Nov 2003 Posts: 98

yes a idle balancing system is installed.
i have not checkt the idle controll unit but this system was good before the engine was taken appart. the milage on this engine is only 30000 km

nzniggles · Joined: 26 Aug 2006 Posts: 64 Location: New Zealand

Mr Fast · Joined: 16 Nov 2003 Posts: 98

well its not a very expensive thing to do, i will try and hope for the best Wink

Otto

nzniggles · Joined: 26 Aug 2006 Posts: 64 Location: New Zealand

Good luck

I hope it works