Naturally aspirated tuning questions
 

Going to the tuner on the 25 may, my first time so i tought seeking some advice on getting the car ready would be good.


Engine is a S4 T2 block with S5 NA (9,7) rotors.
Banzai harness, 3bar map sensor, S4 T2 coils with FD igniter(as per the banzai how to)
The car is running ok on the base map supplied from Banzai racing with their harness, haven't changed anything on the map yet.

What things should i check before going to the tuner, to make shure everything is ok with the wiring and general setup of the pfc?


Someone said that i should use the stock NA pressure/map sensor, and rescale the map, because tuning an NA using the 3bar map sensor would be more difficult, is this true? And how would i do that?

I dont have any.experience with PFC. But i can tell you why its true.for haltech. Haltechs have 32 columns(bars) on the map. For a 1 bar map all 32 bars are divided between -14 vacuum and 14psi or so. For a 3bar the same 32bars are divided between -14 to 31psi. I think the word they use is.resolution. You will have better.resolution with 1 bar sensor. NA engines only.need to be.tuned up to 2 psi. So you dont need 18 extra bars of boost in the map that you will.never.use and will greatly.reduce the.resolution in the vacuum.area.

Typed.with phone at wprk.sorry for.sloppy responce.

Thanks for the answer, but i obviously posted this in the wrong forum, was supposed to go in the power fc forum...

If you have our N/A base map all the cells have already been scaled for vacuum only.

Yes it's your na base map i have, so then there is no advantage to change from the gm 3 bar map sensor(wich is supplied with your kit) to the stock N/A pressure sensor?

That would be a disadvantage since you do not have any idea what the scale and offset of the stock N/A sensor. The 3 bar sensor is only using the first bar for atmosphere since your car in N/A, however it is calibrated correctly.

The disadvantage would be using the 3bar sensor for an NA application. In an NA application using a 1bar sensor you will use aprox 34% of the sensor range. If you use a 3bar sensor you will only be using 23% of the sensor. You can get a gm baro sensor. This will allow you to use 62% of the sensor.

NA tuning with speed density isn't all that accurate. Low vacuum NA engines are difficult to get good manifold pressure signals. The major difference in vacuum is between idle and off idle. Once you are off idle it is difficult to get good manifold pressure signals to tell the difference between part throttle conditions. You will want to use TPS as the main load and have manifold pressure as a fuel % compensation. There is no way to switch this in the PFC. The only thing you can do is switch the main fuel table to a linear line between min and max load sites. You will then use the throttle offset to tune the engine. It is actually pretty complicated to do this with the PFC. Unless you are a pretty skilled tuner I would not recommend tuning that way.

EB Turbo

Go argue in your adaptronic/AEM thread.

It does not matter how much of the sensor sweep is being used. Stop trying to "scare" people into buying your product.

It is not difficult at all to tune the N/A FC with a PFC with a FD 2 bar or GM 3 bar sensor. Obviously a 1 bar sensor would work as long as he could figure out his the offset and scale, since he doesn't have those numbers available and is taking his car to a tuner, then it makes no sense to mess around with a running car for no real advantage.

Attempting to use the stock FC vacuum sensor would be a mistake.

Additionally, the base map already has the pressure rows rescaled for vacuum only which means there are 400 cells for fine tuning throttle tip-in at every RPM range.

The base map was dyno tuned to 199rwhp on a multiple championship winning race car, so it is a very good starting point for his tuner.

You need to double check your math, your percentages are wrong.

I am not arguing. Im just clearly stating facts,

It does. This is EFI 101.


What am I trying to sell him? All he needs is what he already has.

I didn't say it was difficult. I said It wasn't accurate. My recommended method of tuning was difficult.


You just agreed with my comments. Why are you attacking me for saying something that is the truth.


All you need to do is provide the scaling for the stock sensor and his issue will be resolved. If you want you can send me a PFC and a stock FC NA MAP sensor and I will be glad to to figure out the scaling for you. It is cheaper to scale the FC sensor than it is to buy a GM 3bar. I have a bench test harness and a FC datalogit ready to go..

Please explain.. I am interested to hear your thoughts on this.

I didnt make any comments on how you are able to scale the load breakpoints in the PFC. and honestly it doesnt matter. If you have poor resolution with your MAP sensor the engine will move so quickly through the map it will be complicated to get things accurate. The tuning goes past throttle accel. It is dirveability too..

I didnt make any comments on the quality of the base map. and honestly max power means nothing towards the condition of the tune. Make dyno pulls every 10 throttle % and look at the lambda v. RPM traces. This is were a good tune really shines.

My numbers are low because I used more of a working scale. If you want to be a little more vague you could say you would use 100% of a 1bar MAP, 50% of a 2bar MAP and 33% of a 3bar MAP. The math still shows that using a 3bar MAP in a NA application is no where close to being ideal.

EB Turbo

I have read your previous posts in other threads and find you to be one of the largest douche bags on this entire forum so I am not going to bother responding to any of your posts or questions from this moment on. You can continue to spew your garbage advise it really does not effect me in the least.

You might want to consider becoming an actual Forum Vendor before you find yourself banned for violation of Forum rules.

I have in no way tried to sell anything here and I am not bashing you or any of your products. What is up with this hostility? You cannot argue my advice because it is valid. I am more than willing to continue this conversation privately. Like I said I have no intention nor have I taken anything away from you. Calm Down..

EB Turbo