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Discussion Starter #1
ok im just curious when you get a ecu tuned for youur setup, does it matter how much boost you run? to an extent...


reason is i am going to get retuned but my boost controller is not connected,so im only pushing wg spring rate of 7psi, but i plan on connecting the boost controller up later and running around 20psi in the near future...

you know what i mean?

does the tuner need to know the amount of boost planned to run?

yea...
 

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ok im just curious when you get a ecu tuned for youur setup, does it matter how much boost you run? to an extent...


reason is i am going to get retuned but my boost controller is not connected,so im only pushing wg spring rate of 7psi, but i plan on connecting the boost controller up later and running around 20psi in the near future...

you know what i mean?

does the tuner need to know the amount of boost planned to run?

yea...

You need to have your engine setup to be the way your going to run it before it gets tuned. 20 psi is really close to the pump/race gas threshold if not over it in some instances. There is absolutely no way I would run that much boost without having the ecu properly tuned for it.

On a maf car, really the only engine mod you can change without tuning is the cams and even then you really should. On a map car you really cant get away with much at all.
On a maf car like yours you really need to have the turbo you plan on running and the boost controller hooked up properly. They will start your tuning at your lowest boost setting and then increase the pressure little by little after they get the timing and fuel correct at each boost level. They will increase your boost untill they can either not rid your engine of detenation by adding fuel and pulling timing or untill your engine stops making more power with more boost.

Hope that helps.
 

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Discussion Starter #3
that is the best answer i have ever got on this forum, thank you
 

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*YES*

The maps are determinied by RPM vs. TP (ie load), which is almost a direct correlation to MAF voltage (with other things taken in). Basically, the TP scales are predefined in the tune from 0-XXX, where XXX is the max TP to be expected. So, if that max TP is say 120, which is max at 7psi, then you up it to 20 psi and now the max TP is hitting at 180, you can see that between 120-180 on that map you will be getting the same fuel... not good! So, at the very least the TP scales would be need to be readjusted properly, and more likely, the fuel/ign maps will also need to be readjusted for the new scales.

Another thing to note is that if the TP is greater than 80% of the Max TP, it automatically jumps to the last column on the map, so in the above example it would really be more like 100-180 tp load would all be accessing the same fuel.

The down side to this is that by increaing the TP scale to encompass more boost (ie higher MAX), you lose resolution on the scale, ie you you can hit a higher PSI but you lose out on finer grained tuning. There are options though, such as combining the hi/low octane fuel maps into one, you in theory just doubles the horizontal resolution of the map (ie double resoultion on TP, RPM stays same). That requires custom code hacking though ;)

So, in short, yes you need to retune for that. Theoretically by just doubling the stock max TP you should be good for 30+ psi (as the stock tune is good for ~15psi), and doubling that will then gain you 60 psi and so on. The hardest part is getting the rest of the scale in line so you do not get hurt in the loss of resolution.
 

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You touched on a subject I know about. Instead of just giving a short answer (no dont do it) like most people that know about tuning as well would say, I tried my best to convince you not to.

Some people will say things like, "well if your ecu is tuned it should be fine" and stuff like that. They, my friend, know nothing.
 

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Discussion Starter #6
now here is part 2 to my question then...


i ordered the original ecu a while back that is set for 20psi, but the boost controller is not connected like stated above, now running a lower boost setting on something tuned for more, what does that do?
 

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I had this page pulled up for a few mins while I was doing something else and you had not replied to this when I had it pulled up and I seen your post after I posted.

*YES*

The maps are determinied by RPM vs. TP (ie load), which is almost a direct correlation to MAF voltage (with other things taken in). Basically, the TP scales are predefined in the tune from 0-XXX, where XXX is the max TP to be expected. So, if that max TP is say 120, which is max at 7psi, then you up it to 20 psi and now the max TP is hitting at 180, you can see that between 120-180 on that map you will be getting the same fuel... not good! So, at the very least the TP scales would be need to be readjusted properly, and more likely, the fuel/ign maps will also need to be readjusted for the new scales.

Another thing to note is that if the TP is greater than 80% of the Max TP, it automatically jumps to the last column on the map, so in the above example it would really be more like 100-180 tp load would all be accessing the same fuel.

The down side to this is that by increaing the TP scale to encompass more boost (ie higher MAX), you lose resolution on the scale, ie you you can hit a higher PSI but you lose out on finer grained tuning. There are options though, such as combining the hi/low octane fuel maps into one, you in theory just doubles the horizontal resolution of the map (ie double resoultion on TP, RPM stays same). That requires custom code hacking though ;)

So, in short, yes you need to retune for that. Theoretically by just doubling the stock max TP you should be good for 30+ psi (as the stock tune is good for ~15psi), and doubling that will then gain you 60 psi and so on. The hardest part is getting the rest of the scale in line so you do not get hurt in the loss of resolution.
Anyways, I know in the first paragraph you do mention something about timing, but that is the only reference I see towards it. Timing is the key part of a tune. The air fuel ratio is so easy is isnt even funny. The stock timing figures are not going to work too well if all you do is expand your maps (no matter what ecu your using).

Im also wondering where you say
Theoretically by just doubling the stock max TP you should be good for 30+ psi (as the stock tune is good for ~15psi), and doubling that will then gain you 60 psi and so on.
I have a few problems with that comment.
1. Not all turbos are the same and pressure does not equal flow.
2. He hasnt stated what motor and what ecu he is using so you dont know what stock tune he is talking about. It it a rb 20? ca18det? sr20det? ka24e? ka24de (s13, s14)? Or is it a na ca18 or sr that has the turbo added?
3. If he is talking about a s13 ka24de the stock tune is defenatially not ready for 15lbs with any turbo.
4. Just doubling the tp or guessing anything with adding on to tp NEVER has anything to do really with how much pressure you can run. Flow is everything especially with a maf car. If you were really boosting 30psi your going to be running either a custom maf or a lightning maf and and huge injectors which will reduce your tp scale.


Being stuck on psi values really does nothing for anyone. There are turbos that will be lucky to make 200hp on 15lbs and there are turbos that on the same engine will make well over 300hp at 15lbs.

Now Im not trying to pick apart your post or you, I just dont really agree with ideas about tuning. You seem to know your way around the ecu, but maybe not as much on the real tuning side of things?
 

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now here is part 2 to my question then...


i ordered the original ecu a while back that is set for 20psi, but the boost controller is not connected like stated above, now running a lower boost setting on something tuned for more, what does that do?

That should be fine if a ecu is properly tuned for 20 psi because it also needs to be tuned for each boost level under that. But we have a problem. You say your ORDERED an ecu that is tuned for a PRESSURE LEVEL on a car that does not have a map sensor......
Plus 20 psi is a lot of pressure....

any ecu that is BENCH TUNED is a really horrible idea. You should honestly see some of the fuel and timing maps, and see how none of the maps are expanded upon like how bakgwalio was saying. So usually what ends up happening is you max out your tp load very soon and then your stuck with your timing the same no matter how much your turbo is turned up. Your air fuel ratio is usually ok because the tp load limits are usually removed and the afm does the trick to add fuel, but the timing is locked. Now the problem with that is your either going to make horrible power down in low boost, or your goign to have too much timing up in higher boost levels and blow the engine.

If you got a jwt ecu or enthaply, its garbage, I promise. Many of our customers are guys that have blown their engines with them ecus and need a way to actually do it right, or it dont work well enough for them to even run the engine hard enough to blow it...... Now dont get me wrong, some people get lucky and for whatever reason (maybe they arnt hard on it, or their base timing is retarded and they dont know it) their engine dont blow up, Its not like they are getting good gas milage or making as much power as they should.

Really bad idea ordering a pretuned ecu man.....
There is only 1 way to tune a car, and that is to tune that cars exact setup. Not try to use a tune that was for someone elses setup or a bench or commercial tune. Those rarely have good results.
I really want to here one of these companys explain to me how they tune a ecu for any turbo? Where the turbo starts spooling is where things need to start changing on the tune. Ah, I could go on about how bad of an idea it is.....

I honestly wouldnt run more than 12 psi on it if you really care about your engine.
 

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Discussion Starter #9
well mainly all this thread is info, i never really got into the electronic side of things,

i ordered a ecu for my current setup months ago,have never even drivin the car on the road really, just been a project in the making.

not sure if any one has looked at my build thread...

but either way,
the car is at the shop as we speak that does on the site ecu tuning , getting the boost controller wired up so there no problem there any more, so theres no issues.

now there going over the current ecu settings i have and if they dont like it , there going to program there own for me.

just so no one gets to rowdy theres the facts
 
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