Nistune Forums

When i drive it accerates slower than normal until boost kicks and it drives alot better until 10 psi then it shuts off like if the engine was turned off.

Im able to get it to run with a 800-700 injector mutiplier at 13.5 afr at 800rpms it runs jitterly but runs alot better at 10 afr on stock 260cc injectors. It also runs the best when the dizzy is turned compelely clockwise ....... Ive check the belt twice counted 40 teeth between cams and 43 between driver cam and crank shaft. It got dark but tomorrow i will triple check the way the dizzy sits in the head.

Maybe you guys can point me in the right direction. My log is attached.

can you post the binfile as well? did you replace the sparksplugs after the earlier richness?

i have two sets of plugs i've once set gaped at .25 and the other at .40 I have not cleaned them while i was testing with them. Something i will try swaping tomorrow.

if its like hitting a brick wall so to speak, usually that is a timing cut or severe reduction in advance. can also be a plastic inlet pipe/air filter getting sucked closed.

I do have a silicone s-bend inlet which is only reinforced with exhaust tubing in the center. I'll try to change my set up to bypass that.

P.S. Am i suppose to make any changes to my wiring harness this thread speaks about it. http://z31performance.com/forum/viewtop ... f=6&t=7925

I think im falling flat on my face because my injectors are being pegged when i get into boost. Im going to drop in my 480cc injectors tomorrow. timing seems to be fine now. I just need extra fuel on top. I'm acutally pretty happy that my z is improving everyday. Thanks for the help guys.

I looked at your binfile. I didn't realize you where using the stock injectors for this file, things now make a bit more sense.

You should but are not:
using the stock latency with stock injectors
changing ttp min and max according to kvalue
changing tp load scalars according to kvalue changes

you also need to set your tps up properly which is why your timing might be weird at idle (it is in your logfile) and fix your speed sensor, it's not working either

you should be idling in the lower two load columns and not hitting the highest column until max rpm is hit.

In the new version... those tickboxes to ON by default

Note that they dont get scaled (backwards mind you) for MAF conversion right now. Someone pointed that out the other day

So the way i would calculate the ttp, fuel and time scalers would be the whatever change i did to the injector mutipler calclated in percentage?

The ttp min does affected the top engine on idle so i left it stock
The ttp max i set to 255 which control the max time the injectors and stay only

The time and fuel scalers i have not yet touch. I guess ill play with these and see what happens.


Btw: i did not touch the injector latency only the K constant.

I welded on a exhaust the wideband is alot more stable I can now listein to what is doing engine alot better.

That is correct. The calculations are done by the software and if you compare two images (the original and the modified injector resize one) you can see the changes which NIStune has made to the TTPmin/max and TP fuel/timing/VE scalers

Matt ive got you a question, lets say I started off a fresh tune (using stock values), and then did the "injector resize" that automatically takes the K value, and TTP min and Max values to the correct spots.

Well, obviously if your K is cut in half, the TTP scales will cut in half, but lets say that after doing the injector resize, I went ahead and did some adjustments and for this example we will say that the K went from 450 stock, then after the injector resize it took it to 720. Well lets say I ended up moving the K to 530, do I then have to adjust the TTP min and max values myself, or does nistune automatically do that for me?

If nistune does NOT do that, how would I know what to set these values to?
Thanks man!

K constant direct changes without using the injector resize window will not change the TTPmin/max or TP scalers

You have two options if you have worked out a new K value:

(a) Use a previous saved ROM file prior to using the new K value and then resize with the new injector CC size you worked out

(b) Adjust these manually. NIStune takes the Live Edit (different nissan tuning application) approach:

Multiplier = (Original CC / New CC)

New K constant = Old K Constant * Multiplier
New TP scales [1..16] = Old TP scales [1..16] * Multiplier
New TTP Min [1..16] = Old TTP Min [1..16] * Multiplier
New TTP Max[6..16] = 255

The TTPMax is not multiplied by multipliers but set to max limits