I just redid my Speed Density port for H8 DSM ecus.
I am limited to byte size table lookups.
How I have it setup now the max Load is 608.

My calculation gives 1260 Crank HP @7500 rpms @ 100% VE.
But this seems high.


Does anyone know what 608 Load equates to in AWHP?

Have anyone reached these Load levels on the stock ecu yet?

 

Well, if you follow the standard type of setup of Speed Density with a 1:1 kPa to load ratio from 100kPa and up, you're looking at 88psi lol. Most pump gas street cars probably will never hit over 340-360 load/kPa. It's the beauty of Speed Density...you can manipulate the values to make them work how you need them to because you're only following pressure now instead of airflow. 28psi from a stock 16g will still be the same load %/kPa as with a 35r of bigger, only difference will now be the increase in fueling needed in the maps.

 

~74 psi actually, 0-100 kPa/Load is vacuum.

I guess at that boost level 1260 HP seems actuate.
Think Rau and Shep are running those boost levels and making more HP.
Just wondering if my calc is accurate in the real world.

 

Sorry, you're correct, I forget to subtract the first 100 kPa when I converted the 608 lol.

I'm still curious as to where you're going with this as compared to a stock H8 ecu though...do enlighten us!

Do you plan on hitting a max of 608 load/kPa?

 

If you are using the estimated hp function, I have found since first mathing it out that its only accurate with a stock MAF and pumpgas. In otherwords 90% of users can make it work reasonably well, the rest of us should ignore it.

Unless your Load is scaled EXACTLY like a stock MAF at ALL points with no deviation. If that were the case you have a monster street car

 

-> http://ceddy.us/?page_id=16

CeddyMods is my code Mods for the H8 DSM ecus.
I have been trying to catch up with Evo ecus for a little while.
Most of the necessary stuff is done:
Launch Control,
AntiLag,
NLTS,
Map Select,
BigMaps,
CEL on Knock,
1Byte Load,
AirFlow Calcs,
Speed Density.

I plan to add Ecu Boost Control next.


No, I only have a three BAR sensor.

My previous SD code has a max of 304 Load. That meant if you ran over 29 psi, the ecu wouldn't see any higher Load, wouldn't add more fuel and you would lean out and detonate.

JCSBanks code uses a word size table lookup, so this isn't a problem for the SH ecus. But I don't have this option.

I was just wondering what 608 Load equates to, so I can say this code is good until X HP.

 

Very impressive, I have quite a few DSM guys I think that would be highly interested in your work.

I would probably just list it as a max PSI/kPa range for now, as airflow really doesn't have much effect other than with the VE tables. For all practical purposes if you're able to run a max of 29psi on the current setup, then you should be able to use it up to 29psi with any turbo the end user has, whether it's a 16g or a 63mm or even such as a Holset HX40 type which I know is pretty popular in the DSM world. Otherwise I tend to think it would be hard to tag a horsepower level to it since it all depends on a person's build up to that 29psi range. The only problem point with large turbos could be the load % logged with the stock maf to find the initial VE calculations, but once the speed density conversion is done, they can be tweaked accordingly (which is pretty much what I had to do once I swapped to SD since I lost all my previous maf logs and had to set my VE's from scratch).

 

Very impressive Ceddy,

Off Topic......

How the ANTI-LAG is working on your ROM? Do you have a true anti-lag when you lift the foot from the throttle or is just a combination of launch control and ignition retard?

How did you make this working?

 

Its a "Drag Racing" AntiLag, Launch Control + Ignition Retard + Extra Fuel

The Rally Style, off throttle AntiLag, requires air injection equipment the DSMs don't have.

 

Load mimics torque. Thus you can't really do a straight HP conversion unless you also add in the 5250 math for hp to torque. Also, its only really accurate on a stock MAF and even at that the stock MAF starts to loose accuracy at higher than stock flow levels.

If you want to do a HP or Tq conversion what you do is use IPW, the specific gravity of the fuel you are using, and the wideband AFR. You can, from the amount of fuel you are using in lbs/min, the AFR the engine is at, figure out the airflow in lbs/min. This is the most direct and accurate way I know of figuring it out and its hard to cheat this method as well unless you are WAY off on your injector scaling. Its lbs/min of airflow, which is better IMO than hp or tq numbers. Also, if you want to do a Hp or tq conversion, the best way to do that is the rpm over time method like is used by evoscan and datalog lab.

 

But, Load = grams/rev, grams/rev x rpm = airflow/min = HP.


For my calculation I used:

608 Load / 80* = 7.6 grams/rev / 453.59 = 0.01676 lb/rev x 7500 rpms = 125 lb/min x 10 = 1250 HP

1250 Hp @ 7500 rpms @ 100% VE


I'm not trying bench race, or be 100% accurate. Just trying to find an approximation.

Most people who you tell, "This is good until 608 Load", will be totally clueless.


* 80 is from the scaling DSM-ECU and DSMLink uses for AirFlow, grams/rev. L2R99GST did a study with real data and found this number to be 95. I think the difference may be from IAT Compensation and other compensations.


My version of SD allows you to run with a MAF and MAP sensor on.
And you can Log MAF AirFlow and SD AirFlow in real time, simultaneously.
This allows you to get your VE Tables to match the MAF within 1-2% at all points.

This way when you ditch the MAF your VE Tables need no tuning, and AirFlow numbers from the SD emulated MAF are accurate.

 

I thought you were trying to come up with a tq number, but instead your trying to basically figure out VE for the SD stuff. One thing to consider, is that over my years of messing with mitsu airflow sensors (about 10 years now) is that they aren't very accurate much outside stock hp levels. So at some point you are going to be chasing your tail with an airflow sensor that is not acting linear and is basically out of calibration at the higher Hz levels and as such your math no longer applies. What is basically comes down to is, what do you want to use as your standard and what do you want to be variables. Your choices are the stock MAF for a mas airflow approach, or you can use the injector and calculate lbs/min for a speed density style approach. Actually if you know manifold pressure and lbs/min moving through the engine you should be pretty good to go to solve for VE.

Or am I reading what you are trying to do incorrectly?