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Posted: Tue Jul 13, 2010 7:37 pm
by Guy
RB25SX wrote:
U are right if this was a N/A nissan sentra forum, but SX's are all about turbo's and FI.
You
WILL break your turbo engine if u only use the basic ideas of carb and distributor
Turbo engines use the basics for half of the map, the important part is when u get + boost, and that is were they break, running lean, detonation ....
Well you have to start learning somewhere, then you can build on that by looking at all the cars that run turbo's with carbs and distributors. Hmm lots of those still seem to work with the good ol' basics.
Posted: Wed Jul 14, 2010 7:59 am
by Draco
Guy wrote:You know what, an engine is an engine, they may have their own peculuarities but the basics are the same for all.
Perhaps put aside trying to learn to tune electronically for now and get the basic ideas of how to tune a carb fed, distributor ignition engine down first. This will give you a good grounding on the basics of timing and fueling, without the confusion of electronics and being able to do just about anything wrong with fuel injection.
Example, a simple centrifugal advance distributor will be fully retarded at cranking, so its a no brainer, thats all you get with that setup, whereas with an ecu you can get full advance at crank if you want, not that that is what you want.
So rather start learning by reading up on tuning older style setups, it will help guide you/ narrow your choice of tuning options compared to just jumping in with an ecu where it can give you whatever you want, no matter how wrong it is.
Thanks for the advice Guy, the thing is the management is basicly set up, tuning is closish, all I need to do is make the small adjustments to get it as close as I can to right, if it was a story where I had a blank map and had to start from the beginning....it would have been a whole other story.
I have thus far done things like retarding the timing from where it was very high to less to make it safer, got my fuel map "smoother", preveously when I got up to a robot and took the car out of gear the revs fell and the engine almost died, now it settles nicely to where it needs to idle.
Posted: Wed Jul 14, 2010 8:08 am
by Draco
This morning to work I recorded while I drove, I still need to review the recordings but what I have seen is that I am leanish on slight throttle and boosting, just off throttle cruising I am very lean.
Still struggeling with the cold start, car starts but dies 1-2 seconds later, it takes about 4 tries before it keeps going, I have inriched it on air and engine temp adjustment and lifted the timing slightly, still it struggels to keep going in the morning when started, I will still play with those and see where I get it better.
At the moment I am using the AFR on the program installed by Barend, I don't trust it much but the way I see it, it's better than tuning according to the plugs, as I have done before, a there or there about afr is better than no afr I suppose.
Posted: Wed Jul 14, 2010 8:15 am
by Gary57
Derek, once the car is started and your finger is off the key the car is no longer starting so you are not looking for any starting info, you need to increase your post start enrichment...
Posted: Wed Jul 14, 2010 8:25 am
by Draco
Thanks Gary, yes I am doing that, little by little, I have seen that when I start the eng temp is around 0 - 6 'C, I have it at 34.1 %, I will increase some more and see what it does tomorrow morning.
I also read in the software help that when tuning the fuel overall trim must be on zero, mine is set on 39.5, zero'd it yesterday and directly saw that the engine is getting to little fuel, rather than retuning the whole fuel map and other modifiers I rather put it back there and go on.
Posted: Wed Jul 14, 2010 8:31 am
by Gary57
I would do the same BUT that 39.5 will effect your other modifiers...
Posted: Wed Jul 14, 2010 8:35 am
by Draco
The way I see it is that the modifiers was set with the overall trim on 39.5, so I assume the modifiers was set according to that trim, I'd rather leave it like that than redoing all the modifiers with the retune.
Do you agree?
Posted: Wed Jul 14, 2010 8:43 am
by Charlvdw
On the xms there a prime function where you can increase fuel below 400 rpm. Isn't there something like that on the wolf? Or do i have the wolf by the tail?
Posted: Wed Jul 14, 2010 8:48 am
by Draco
They have all sorts of modifiers, post start inrichment, target rpm according to engine temp, initial centre engine temp.
Posted: Wed Jul 14, 2010 9:02 am
by Gary57
But when you are adding say 40% fuel you are actually adding 40%*34.1%, its a % of a %.
Posted: Wed Jul 14, 2010 9:04 am
by Draco
Can you simplefy please Gary....
Posted: Wed Jul 14, 2010 9:09 am
by Charlvdw
Gary57 wrote:But when you are adding say 40% fuel you are actually adding 40%*34.1%, its a % of a %.
40/100 X 34.1/100 = .4x.341 = 0.1364 = 13.64% is what you are actually adding.
Posted: Wed Jul 14, 2010 9:12 am
by Draco
Ok....thanks....
Some guys are just too wise for their socks....
Posted: Wed Jul 14, 2010 1:45 pm
by Pinkfluffybunnys
Big Up for doing it yourself.
Your knowledge can only grow...
Posted: Wed Jul 14, 2010 1:48 pm
by Draco
Pinkfluffybunnys wrote:Big Up for doing it yourself.
Your knowledge can only grow...
Thanks man, make no mistake, I will take it to a professional some time, but slowly but surely I will learn....