ECUTune Stage III twin screw supercharger sign up

[longassname]

I posted the thread on the stage 2v3 software. It may be of interest for you stage 3 guys as it gives a good explanation of the maf meter conversion.

http://www.subaru-svx.net/forum/show...415#post324415

[mikecg]

Alright where's my up-dates????

It's been too quiet.

[longassname]

I've taken a little time to get some software work done. I recently got back the test reports on the injectors we will be using. The software I made during the testing phase was based on the test reports for the factory injectors, the advertised flow rate of the new injectors, and latency values that have worked for other people on other cars. Of course the test reports are dead on accurate--they are advanced tests based on my criteria to get all the exact information I need to know for doing the software perfectly.

Having made the precise mass air flow meter measurements and now having the fuel injector test reports I was ready to start putting together the final version of the software. I won't get into the numbers again as you already know the basics on the flow rate of the injectors and explaining the the more complex stuff that controls the timing of when fuel is injected is complex and unneccessary--though an important ingredient of performance. What I have for you today is the timing and fuel maps.

Some reworking of the maps is an inherent part of changing the fuel injectors. The fuel injector change doesn't call for changing the shape of the map but since the values for calculated load which make up one of the axis of the maps are changed when the fuel injectors are changed it is necessary to rescale the values of the load axis on all maps. The problem you run into is when you rescale the values you don't necessarily get whole #'s so it takes some work to calculate from the original table values what the values should be with the new scale so that the shape of the map stays the same. We do this but we also take it a bit further. The load range of the factory maps does not include the increased load range we are running with the forced induction. When choosing our new scaling we expand the load range covered. We then use the data from the factory table to fill in the part of the load range corresponding to the original range and extrapolate new data to fill in the extended range based upon the characteristics of the engine, general tuning principles, and experience with other fuel and ignition timing maps.

I'll show the timing maps first as it is easier to understand and a cleaner looking map in the factory form. The SVX uses both a lot and very little timing due to the engines design. The ignition timing map goes all the way from 50 degrees at high rpms and low load to 0 degrees at low rpms and high load. Here's the factory timing map:



Here is the stage 3 timing map. Allthough it is actually the same number of datapoints you can see it as a larger map containing the factory map. It now covers a larger load range on out to where values for both low and high rpms are 0. The original values are not decreased to retard the ignition timing. With the load range properly expanded there is no need to decrease the ignition timing at the factory load levels. We simply need to have the correct values at the higher load levels which correspond to boost conditions.



As I have said before the factory fuel map is a fuel revision map. It does not say how much fuel to inject. It says how much more fuel to inject above the amount the ecu calculates is needed to get an afr of 14.7 based on rpms and load. So you have you picture the plane on which these maps is built as being an afr of 14.7 and the values of the tables are the additional fuel added to reach a lower afr. The factory fuel map is a bit ugly looking but can be understood with a little knowledge and though. Normally fuel maps climb as rpm and load increases. At frist glance the SVX fuel map looks to be backwards. It isn't though. You have to keep scale in mind and remember this is a revision map--the difference between the highest and lowest points in this map is only about 1.5 in the afr. That said to the trained eye what you have here is the traditional map you would expect with a hump of extra fuel added at low load accross the entire rpm scale. This map won't look so ugly as part of our larger fuel map.


I expanded the load range of the fuel map just as I did with the ignition timing map. The values on the left side of the map are mostly taken from the factory fuel map. Values on the right side of the map correspond to boost conditions. Some of the values for higher rpm ranges on the left side of the map were changed as well. The original factory maping can be seen in the blue area. The rest is my doing. I don't want to get into explaining map creation any more than I have but you can get the general idea of increasing fuel as rpms and load increase. This map should work extremely well for us.


The questions on the stage 2 sofware have settled down and I have the final version of the stage 3 software ready to go in the car when i get a chance to switch back to the nismo injectors. I'm going to go get lunch and get back into metal work. Today I'm going to work on cutting the metal to enclose the left and right sections of the manifolds.

[Chiketkd]

Originally Posted by longassname

The questions on the stage 2 sofware have settled down and I have the final version of the stage 3 software ready to go in the car when i get a chance to switch back to the nismo injectors. I'm going to go get lunch and get back into metal work. Today I'm going to work on cutting the metal to enclose the left and right sections of the manifolds.

Nice. It'll be interesting to see how much of a noticeable change you get when you install and run this revised Stage 3 software in your test car. You might even get the nerve to take it to redline a few times...

-Chike

[longassname]

Originally Posted by Chiketkd

Nice. It'll be interesting to see how much of a noticeable change you get when you install and run this revised Stage 3 software in your test car. You might even get the nerve to take it to redline a few times...

-Chike

I have 2 things holding me back from that. Johny law and I don't have my torque mount installed.

[TomsSVX]

are gonna need engine straps to keep the motors from jumping out of the car???

Tom

[Earthworm]

...or maybe straight jackets for the crazy owners!

[TomsSVX]

Well the straps are to hold the engine in, the wives are gonna have a hard time getting their husbands out

Tom

[SVXRide]

Michael,
Thanks for sharing the maps! It looks like the timing maps actually support the "dip" we've seen in the Hp curves (around 5k rpms) from dyno runs. Is this true, or are my eyes just playing tricks on me?


(note: dyno curves are my "baseline" curves - only change to the stock configuration was a high flow secondary cat and high flow resonator)

-Bill
p.s. any way you could PM me the Excel file that has the stock timing and fuel maps in it? I'd like to be able to rotate the plots to get a better understanding of what's going on. Thanks.

[Chiketkd]

Originally Posted by SVXRide

Michael,
Thanks for sharing the maps! It looks like the timing maps actually support the "dip" we've seen in the Hp curves from dyno runs. Is this true, of are my eyes just playing tricks on me?

(note: dyno curves are my "baseline" curves - only change to the stock configuration was a high flow secondary cat and high flow resonator)

-Bill

I noticed the same 'dip' during the baseline dyno of my car Bill.



-Chike

[Jnthn_Sctt]

Originally Posted by Earthworm

...or maybe straight jackets for the crazy owners!

Hey!!! I resemble that remark!!!

[SVXRide]

Looks like the factory fuel map is also consistent with the dyno results....

Michael - think you can post the factory fuel map rotated around so the rpm scale is to the front (with load projecting back into the page)?

-Bill

[longassname]

Originally Posted by SVXRide

Looks like the factory fuel map is also consistent with the dyno results....

Michael - think you can post the factory fuel map rotated around so the rpm scale is to the front (with load projecting back into the page)?

-Bill

Bill,

Both of your observences are correct. There are humps in the fuel map at the same two places where you see the dips in the timing. Obviously those are areas where the engine naturally has a tendency to want to detonate and can't run as much timing and needs a richer afr. Let's not talk more about it now though this thread is for updating the purchasers of stage III. Speeking of which I do have pictures of today's work which i will be posting tonight but first I need to eat dinner (having just gotten home from the shop at 11:15).

[SVXRide]

Originally Posted by longassname

Bill,

Both of your observences are correct. There are humps in the fuel map at the same two places where you see the dips in the timing. Obviously those are areas where the engine naturally has a tendency to want to detonate and can't run as much timing and needs a richer afr. Let's not talk more about it now though this thread is for updating the purchasers of stage III. Speeking of which I do have pictures of today's work which i will be posting tonight but first I need to eat dinner (having just gotten home from the shop at 11:15).

Michael,
Thanks for the response! Nice to see I'm not the only one up at this time on the East Coast
I agree on not "highjacking" this thread any further...think you could start a separate thread on the stock ECU's maps? I will be going back to the dyno later this year and want to be prepared...
-Bill (looking to squeeze every last Hp and ft-lb out of the NA EG33 )

[longassname]

Here are the drive snouts. I mentioned them ariving before but they are about to become important. I'll be using one probably tomorrow to fit the supercharger on the engine and measure what size I need to get the plates cut for the discharge flange. I'm out of 6061-t6 so I might as well get it cut to size while i'm buying it.




Now to todays work. Here's the bottom of passenger side of one of the manifolds after cutting it to shape but not formed. On this side of the manfold we are forming the plate to close off the bottom and will weld in a seperate plate to close in the sides beneath and behind where the discharge flange will weld.


This is 1/8 5052-H plate. 1/8 is pretty thick plate but since it's 5052-H it is still formable and the press brake set up we have can bend just about anything. Here is the plate from the previous picture in the press brake being formed, then after forming, and then cut off to match the manifold.






Here you can see the passenger side parts finished for all 5 of this batch and 2 of the driver's side done. On the drivers side we are able to form the plate to create the sides as well. Obviously we'll be cutting out the area on the sides which will be above the discharge flange. I will wait until after the discharge flanges are done to this so that I can mark the cuts accurately.