Its all about time invested, for business quicker is better. Without losing quality, but I have issues with tuning since my OCD kicks in and it has to be perfect. I spend hours developing my own maps to get it to behave the way I want it to when I’m tackling new platforms. I refuse to touch a car until I have my basemap developed that I’m happy with.
Awesome thank you.It basically models how the engine transmits heat to oil at a given load and speed and then how the oil dissipates the heat to the cooling system and to the environment based on factors like ambient temperature, vehicle speed, coolant temperature etc. I can dissecate this sometime later but the goal is to replace this with an actual read from the stock sensor present in some euro vehicles.
To deal with heat I modeled the LOAD limiting tables to limit load relative to intake temperatures, this prevents the system from heating to a point of boom boom. You could use "pressure ratio" tables also but they are a little tricky since table values does not translate directly into boost, as it is a relation between air pressure in the turbo inlet x air pressure in the turbo outlet so it is easier for me to use LOAD instead.
That table comes maxed out from the factory, but what I did is:
I tuned the car using that one line torque table until I reached the expected result. Next I get all datalogs from the dyno pulls to see the LOAD values for a given RPM, and with that I populate the load limit table at reasonable temperatures. At higher temperatures I lower the values so when heat starts to build up, ecu finds a load limit, thus limiting boost, and keeping things cool.
Let me ilustrate.
this is the table in its stock form:
Now from checking datalogs I saw that I run at around 250% load until around 4500 rpm tappering to 210 up top. I then assume that it would be safe to run this much load up until 60 degrees celsius IAT and from there graduelly reducing load so this is what it looks like now:
This way, at lower temperatures this table will not limit the tune, but when it starts to rise, boost will drop to let the system cool again.
Yeah I had to walk away from some products because of its a PITA for sure. Hondata is still able to disable o2 downstream sensors but I feel that will probably go away soon. EPA should be targeting actual factories and such and not worry about a minimal amount of cars in comparison.
Great job my friend! Also quick question I know you were monitoring coolant temps, were you reading off ECT 1 or ECT2? I have found just with stock radiator a difference of about 20F or 12C difference from pre radiator to post radiator temps. Would be nice to see the difference pre and post on a PWR radiator.Hello guys! It´s been a while since I don´t post here!
But I have some updates:
I finally got the car from the dealer, and got most of the parts installed.
Got a chance to do a few laps at interlagos, and it was a lot of fun except for a lot of overheating lol.
I had to lower the power to less than stock in the midrange with a bit more juice from the MHI Stage 2 up top.
I have the MHI in my car and have tuned a couple others on P700 and I can say that the MHI is a much better turbo overall.
But lets start from the beggining: (sorry if this looks like a build thread lol, but all things will connect at some point)
First I got the car and some parts that arived:
installed them:
And then I dynoed the car with a very very conservative tune, because I knew that even with the PWR track spec the car would most likely overheat lol so I went with 20-21psi max boost, .77 lambda, and a lot of timing to keep EGT down.
One cool thing I tested successfuly was to model some tables that limit power from COOLANT TEMPERATURE, like this:
This is a factor of maximum torque, so at 110 degrees celcius, the power would drop 20% and so on.
This worked very well at the track, together with the PWR radiator, that let me do 2 full laps before going over 110C that I consider to be the safe limit, BUT I would lose around 10mph at the straights with the power reduction.
SO I just lowered the power by - A LOT - and got to do a couple more laps lol.
this is the tune I sarted the day with, and ended with around 310-320whp to keep temps kind of steady
Another thing that pissed me of at the track, was teh fact that I could not run under half a tank because the car would go into limp mode because fuel pressure would drop.
So I bought a used fuel pump from a 1.5 turbo (should be the same pump) and did a lot of bench testing:
Whatr I found out was this: The flow in the venturi works from the return line via a valve that keeps like 1 bar of pressure at the venturi tip, and that fills the cup from the bottom.
What happens when you have a lot of power or high fuel demand (in my case, E30 with very rich AFR) is that when you use a lot of flow from the pump, there is not enough flow in the return line to feed the venturi.
That causes the pump to use all the fuel in the "pump cup" faster than it can refill itself until pressure drops to 0.
So I decided to rethink the entire system, by adding a Walbro 450 to the system, I tested it at the bench and moved the venturi to the FEED LINE, because with this pump I have so much extra flow that it would not be a problem. I tested different jets at the venturi until I got a good compromise:
With this 0.7mm tip I uses around 60 liters per hour while it moves around 360 liters per hour to fill the pump cup.
I liked this a lot. I used all stainess steel and POM (polyacetal plastic) parts, so everything is rated for gasoline and ethanol and moved the filter to the engine bay as an external 10 micron unit.
But before final assembly I decided to test the power consumption of the fuel pump, and it shoed me 19 amps at 70psi.
I didn´t like it since the stock pump take slike 5-6 lol.
So I went 5 steps back and started thinking of something else:
I mounted an AEM340 (very available here in brazil) and modified the entire system in a way that now the venturi works from the feed line not the return. Just like on the Walbro 450 setup.
I machined a stainless steel cap to block the stock fuel pressure regulator and instaled an adjustable ford FPR where the stock return valve was, and made stainless bracket to secure it in place.
I am now in the process of prototyping a clip to secure the pump in place since it is much bigger:
I like this setup much more since it draws like 12-13 amps.
Now as far as water temperature is concerned, I found a very cheap VW side mount radiator and prototyped a mount for it, inside the bumper, in the way of one of the brake ducts, I need to do some final adjustments before I laser cut this in stainless:
THis should help a little bit more keeping temps down.
Although at the middle of the process, I started wondering: Isn´t our ECT1 temperature very high, because we read it AFTER water passes trough the "headifold"?? Because in other cars, temperature is measured around the combustion chambers, but in this case we measure it at the head outlet so that means we read water temps after it cooled the exhaust gases so that is not necessarily the temperature around the chambers..
Now after all the talking:
We did talk to the guys at Hondata, and they are great, and have a great product. In the upcoming months I believe they will be adding lots of great tables for tuning big turbos, flex fuel and a lot of great features.
Since most people here will use their platform for tuning, and not straight to the ecu, I am thinking of doing a big guide to explain all the functions after they are implemented and how they relate to each other. I know most people here are not familiar
Sounds good! I will hopefully begin more testing too when January rolls around when the tracks open back up. If anything text me you got my number.
