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Discussion Starter · #1 ·
Good morning, everyone!

I'm just swinging in to share some results we had over the weekend with finally being able to spend a bunch of time with the turbocharged K23A1 platform in the 2007-2011 Acura RDX on the dyno. This car doesn't really get a lot of love, despite being the only current turbocharged Honda available in the USA, and the potential that it holds for a fun driver.

We removed the propeller shaft that drives the rear wheels in order to test on our in-house DynaPack Evolution 3000 2WD dyno in front-wheel drive configuration.

This particular example was tested with only one of our custom intake arms (3" diameter, like many of the off-shelf aftermarket pieces, nothing special at all. This also keeps MAF scaling close to stock.); beyond the intake arm, the car is completely stock. We performed the tuning with a Hondata FlashPro unit.




The car has been running around on a simple street tune for a while, but we wanted to compare the engine in stages, so for initial testing yesterday we returned the ECU to stock. With the ECU on the OEM calibration, the tests produced a best of 189whp / 206wtq, with boost tapering to 8psi at redline. The stock power rating is 240hp / 260tq at the engine, giving us roughly a 20-22% drivetrain loss in FWD configuration on our machine.

Next, the "street tune" file was loaded. The street tune was also done by me using OEM-like timing table curves, and OEM-style VTC tables; we didn't want to get too crazy on the street without knowing how much to trust or distrust the OEM knock sensor sensitivity, so the goal was to minimize knock and up boost, essentially. With this calibration loaded, the results were 218whp / 241wtq, with boost fairly steady at 14psi falling to 13psi.

At this point, we took the liberty of completely reshaping the WOT Lambda Adjustment, ignition timing, and VTC target tables, and also making adjustments to the knock ignition limit/retard tables. Knock sensitivity was left alone, as we found it to be fairly accurate. From Honda (as well as Hondata), cam advance is very limited, with the majority of the calibration never advancing past 0deg (in boost, no cam advance is used). After a few pulls dialing in the new shapes of these tables, we found a BUNCH more torque down low, and fair gains everywhere else. With these adjustments, the results were 255whp / 317wtq, with peak boost of 16psi early on, with boost falling to 13psi up top.



Dotted red = Stock ECU tune
Solid red = Street tune
Solid pink = Final dyno tune

Here's a comparison of stock ECU calibration versus the final tuned version.



I would like to note that all tests were performed within 1.5 hours total of each other, with IAT's monitored closely to keep them consistent in the 120-130deg range. These cars are very sensitive to heat soak with the stock top-mount intercooler when dyno testing. Injector duty cycle was also very high; 97% with an 11.6AFR fuel mixture. Knock count was reduced to "0", also. With both the OEM Honda calibration, and the Hondata reflash, ignition timing is through the roof; they are constantly relying on the knock sensor pull a bunch of ignition timing. By rewriting the ignition tables completely, we have eliminated the over-retard required. Target boost was also turned up as high as the engine allowed; without removing exhaust restriction, no more boost can be made. Because of this, boost does waver a little, making the 'waves' in the torque curve.

I definitely want one now.

Thanks!

- Derek
 

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Very cool. I always wondered about the RDX. Big time results for the soccer mobile! Thanks for sharing.

Do you think the rest of the drive train can handle the big gains? AWD reminds me of my friends old AWD Talon that went through clutches and transmissions. But he drove it like he stole it.
 

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Discussion Starter · #11 ·
Just a quick update on this:

The car on the street tune previously ran a best of 15.0 @ 89mph.

Here is the latest, with just the dyno tune. We are very close to the stock turbo 1/4 mile record, with probably the least amount of modifications.



We're going to make a catless downpipe/midpipe combo for it, and toss some ID1000's in for some E85, and see if we can crack a solid 13.XX @ 1XXmph.
 

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Discussion Starter · #14 ·
Another update on this car:

The customer decided to toss a DW65c fuel pump and a set of Injector Dynamics 1,000cc injectors in the car, and we retuned on 93oct again, and on E85. The figures on 93oct were a little lower than the last time we tested, but within 10whp or so. As you can see, E85 helped it out a ton down low (where we were able to up the boost and bump ignition). Up top, the car still won't make any more boost (presumably from exhaust restrictions with the stock downpipe/cats/exhaust).

Solid lines are E85, dotted are 93oct.


Fearing the transmission wouldn't like all that torque, we turned it down to 340wtq or so.

Friday night, he took the car to the drag strip, and broke the RDX stock-turbocharger record, first by running a 13.7 @ 98mph, followed by a 13.68 @ 99mph (his second pass was actually against a Jeep SRT-8, for comparison). The quickest/fastest RDX known has gone 13.67 @ 101mph, with a billet turbo/full exhaust, so I think we've got that covered on the stock turbo after some exhaust modification finally.

https://youtu.be/4e4KN23TpYY





 

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:notbad: i bet that thing is tons of fun and super comfy driving around town. This guy probably gets mad bitches.
 

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Is the 2.0x 60' easy to hit in the AWD? If so....it gets out of the hole pretty quick.
It only sees about 4-5psi due to the throttle being limited to 20%. Safety thing I guess. Before the j35 tb I only saw 2-3psi and less launch rpm as well by about 2-300rpms.

:notbad: i bet that thing is tons of fun and super comfy driving around town. This guy probably gets mad bitches.
It's actually my wife's vehicle lmao
 
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