Hi, going to be building this motor for my 03 Accord. Going to be running Hondata's K-Pro on an RSX (PND) ECU with a dual harness. I've downloaded Kmanager and I'd like to start a preemptive basemap for the motor, the thing is I can't seem to open or edit anything in Kmanager, I'm assuming because I haven't connected it to an ECU? How can I get a file to edit? Might anyone have a .kal file of either a basemap for a K24a4 or a finished tune they wouldn't mind sharing? Also I'm curious what parts of the engine's functions are run by the PND ECU when running dual ecus like you have to when running K-Pro on Accords and what functions are run by the Accord's RAA ECU? Is it just straight up, the PND handles the motor and the RAA handles the rest of the car's functions as it has? Like, how different are the K20 and K24 maps? I mean being almost half a liter in displacement apart they must run different maps. Here's my setup:
(Yeah I'm including parts that aren't relevant for a tuning question but hey)

TURBO:
**Garrett GTX3076R
T3 1.06 A/R
What do you Guys think of this turbo? I'm looking to make around 600whp no less than 500. From the compressor chart on Garrett's website it looks good for my setup. I've calculated that I will end up running about 37psi.

Darton Sleeved K24a4 Block
Skunk2 Tuner Series Stage 3 Cams
Skunk2 Alpha Series Valves
Skunk2 Pro Series Dual Valve Springs
Skunk2 Pro Series Titanium Retainers
Skunk2 Pro Series Intake Manifold
Skunk2 Pro Series 70mm Throttle Body
Skunk2 Alpha Series H-Beam Forged Connecting Rods
Wiseco Pro Tru Forged Pistons Sport Compact Series 87mm Bore
OEM 02-06 Acura RSX Type-S (K20a2) Oil Pump, Timing Chain, Guide and Windage tray
NGK Iridium IX BKR8EIX # 2668 Spark Plugs
Private Label Driven Sidewinder T3 Turbo Manifold and Downpipe
(PND) ECU "RSX"
KTUNED Dual ECU Harness
Hondata K-Pro
Hondata Traction Control
Walbro 400 LPH In-Tank Fuel Pump
RC 1500cc Fuel Injectors

Thanks guys,
-Ian

 

There's a map repository, what they call the vault, on the Hondata support forums if I recall correctly. everything from base maps to full tunes.

 

The GTX3076R is very deceiving. The compressor map shows up to 61lbs/min, but the turbine wheel can't support it, no matter what giant housing you put on it.

You're close to 35R size or something similar. To try and push that turbo 37psi makes no sense at all

 

GTX3576r

 

Actually yes. That turbocharger and similar would do much better in a smaller turbine housing for those kinds of needs on a K24A2 like that.. And no, it does not have to be a divided housing to perform a better powerband. That's a twinscroll vs. Divided housing misnomer.

 

Yeah I'm not so sure that I will need to be making that much boost, I think my calculations are a little off. I had a feeling the gtx3076r might be a little small for what I'm trying to make power wise. I understand I'll have some lag, I'm not too worried about it and I realize I will only be able to make so much power but I am aiming for 550 or so, so what would you recommend? The gtx3576r? I plan to go nuts learning about tuning and working closely with my tuner to avoid too much lag and creating a ridiculous tune.

As far as airflow of the stock motor this is what I've calculated using this formula I found:
100% VE AIRFLOW (scfm) = DISPLACEMENT (ci) x RPM / 3456
These #'s below are the airflow through the motor @ 100%VE which from what I understand is rarely achieved in a gasoline engine so the real VE of a K24a4 will be different than these #'s. These #'s would be airflow at sea level, 59*F with wide open throttle. (Airflow is expressed in sea-level-standard-day cubic feet per minute)
1,500rpm = 63.56 scfm
4,300rpm (estimate of VTEC crossover to be set by tune) = 182.22 scfm
6,500rpm (stock peak hp) = 275.5 scfm
7,200rpm (ideal peak hp-of built motor) = 305 scfm
8,000rpm (ideal redline of built motor) = 339.01 scfm

From what I've calculated the required VE for 600hp is 258%. Which doesn't really make sense seeing how the motor makes 160hp on like less than 90%VE and 600hp is 3.75 times that. 258%VE is only 1.58 times what 100% VE would be. Basically I'm reading alot of #'s haha


This is the formula I found for Required Airflow so I think I can calculate the required airflow for 600hp which is really what I need, not necessarily the 600hp VE:
Required Airflow (scfm) = 2.723 x Fuel Flow(pph)
To find Fuel Flow in pph (pounds per hour): 0.1339 x 600hp / 28% Thermal Efficiency = 283 PPH
This means @ 600hp I will need to have 770.609scfm flowing through the motor. This will be @ 7,200rpm because thats where I want to make peak power. For turbo air flow chart reading reasons I need to convert 770scfm to lbs per minute. Which means I need to use the following formula: P(psia) x V(cu.ft./min) x 29 divided by
(10.73 x T(deg R))
(13.95psi (garrett's corrected psi) x 770scfm x 29) / (10.73 x 85 degrees Rankine or 545 degrees) = 53.3lbs/min

I think I might end up going with the GT4088. Yeah it's a little big but It's designed for the 400-725 range so I could make my power in the slightly more than 2/3's of the turbo's power range. It will also support a higher peak hp if I want to make more either on my initial tune or later on, my fuel system, engine and management could all support it. I am going to use this car as my summer daily, I'd love to be able to hit 100mph faster than hell but I'm not really looking for hp, more torque ya know? Not looking to run down the road at 150mph, there's nowhere to do that and its just downright dangerous.

 

Ah.. real calculations for once. But for an adiabatic analysis that you're using, you can't use 100% VE. That's only a mathematical / theoretical probabilty, but an actual impossibility.

Did you account for additional intake ambient air temp (in Kelvin) and Intercooler pressure drop? That all depends upon the intercooler that you plan to use. (And no, Size alone will not determine pressure drop).

I'll see what I can come up with based upon your assumptions and displacement calculations.

 

Hell yeah man, sounds good. I just started a new thread in forced induction that is a list of different parameters, values, formulas, just good things to know when analyzing/building a motor. You seem like someone who could be a great contributor, you should check it out.

 

Still haven't found any basemaps for a turbo K24a4. I need a startup map. I guess I should check with shops that tune for charity .kal files?

 

So, I'll keep it quick. what I did was use my calculations with a few more real world numbers. Some things I did that GoodUserName did not

- Used .93VE for the K24A4
-Displacement is 2354cc (143.65CI)
-10F* above ambient for intake temperature ( Lowers whp to real numbers for those hot days above 80 degrees
-Used 4300,6500,7200,8000 rpm sets as parameters (There's no sense in using 1500rpms.. Its too far outside of any usable range
-Assumed a .6psi pressure drop for the intercooler and IC (I assume you didn't go cheap on the intercooler, but not completely sure. A Garrett loses the least at about .4psi. Mishimotos and Precisions get average about .6 & .8psi drops respectively.
Used 2.4PR for measurement (Equal to about 20psi of boost pressure)


Basically this gives about 520whp at about 20psi is used with an intake temperature of under 100F* at the intercooler pipe into the throttle body.

For the GTX3576R or Predator, you're within the 73% to 68% adiabatic efficiency, with 76%-77% being maximum efficient for the turbocharger. once you get to about 8000rpms, it does go about 7-10lbs/min outside of the zone, but that's still not a surge point because the efficiency of the intercooler "stretches" that efficiency map of 68% about another 10lbs/min.

Here is where I placed your Corrected lbs/min airflow of the engine based upon the parameters above.

4300rpm=37.1lbs/min
6500rpm=56.0lbs/min
7200rpm=62.1lbs/min
8000rpm=68.9lbs/min

what this tells me is that overall, 60lbs/min-63lbs/min compressor wheel is great, but what you're forgetting is turbine wheel efficiency. For your needs, the better powerband will be at over 20-24lbs/min of turbine efficiency vs. the 60mm turbine wheel of the GTX3076R which has a maximum turbine efficiency of about 22lbs/min. This means that the turbine wheel is easily going to work MUCH harder than the GTX3576R. So, that's where it puts you.

I had a similar discussion with UTAH TSX, and he was in the same position, but in a much lower static compression which will affect his boost threshold recovery negatively..

So, we may disagree on the math you use, vs. mine, but i told you the differences of the parameters I used that I believe are more accurate to "real world conditions". But its up to you to decide which you want to follow. I try not to get into mathematical debates. In the end its theory.
We may agree or disagree with your num

 

Numbers were a discovery and likely one to get us to where we are today but they are only a magnifying glass for our world yet are believed to be true and just. Just like you believe the black dots on the screen mean something, there is more going on there.