ljcolomacks

Looking for the best $$ for horsepower mods for my Black Pearl 09 RDX! After lots of research on these forums I have come up with the following.

Mod list:
Flashpro
DW 600cc injectors w/ DW fuel pump
RV-6 Downpipe

Other mods like the ATLP cat-back, ETS intercooler, CT-E or K&N intake, seemed like lots of money for little gains. Agree/Disagree?
Any recommendations for maintaining reliability with these mods on my RDX?

ljcolomacks

Anyone know if I have to replace the fuel pump, or would the stock fuel pump be sufficient for 600cc DW injectors?

csargemg

I would strongly recommend getting Bosch-style EV14s in whatever size that you choose.

VitViper is probably going to give you the best results on tuning.

Don't buy an aftermarket intake until you literally peg your MAF housing. Then consider a factory mod. Airflow smoothness and fuel delivery precision are what this ECU demands to not drive like garbage.

The stock fuel pump is just fine all the way up to 800s at least

Based on the above, for the 'first tier' of mods:

Flashpro
RV-6 Downpipe
Rywire harnesses for Deatschwerks
800cc ev14s (works great on both stock and upgraded turbo)
Bigger transmission oil cooler, replacing factory

You should be able to hit around 200-210 AWHP with that, and with great driveability (Stock is about 179)

Going above that will require a sort of range of things together to work efficiently, such as doing a turbo upgrade, intake mod (modied factory intake is looking the best right now for smoothness), throttle body, intercooler, at that stage.

From my experience, the Eibach springs and Progress rear sway bar are the best bang for your buck so far as suspension goes. For brakes, steel lines and EBC Redstuff pads.

There are a number of pitfalls, but it seems so far what happens is that the turbo is what maxes first (stock turbo reaches the limits of the CFM it can flow) and then upgrading the turbo means the MAF sensor goes past its limit, and so next the intake needs a MAF scaled housing, and so on.

So it's best to think of it in 'stages,' silly as that is, because you only get benefits when the overall system's ability is improved, I suppose. I presume you don't want to get lost in the weeds, and losing a lot of time and labor.

Send me a message if you want to talk on the phone.

Slow98teg

Flashpro of course.
3.5" intake. has to be custom made though.
3" downpipe and midpipe. can leave stock muffler. keeps it quiet.
No sense getting 600s. youll max those out relatively quick. Just do 1000s and never worry about it
ETS is a good upgrade . I never did it but others have had good results .
if you're anywhere near Carlisle PA i highly suggest going to Innovative Motorworks. even if you're not a rdx guy from NC drove all the way up to get tuned.
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TheWrench116

iTrader: (1)

Flashpro
RV-6 Downpipe
Rywire harnesses for Deatschwerks
800cc ev14s (works great on both stock and upgraded turbo)
Bigger transmission oil cooler, replacing factory

if you want more power then this the next step would be
3.5 maf housing
Blouch Turbo upgrade

more then that ^

E85

more then that ^

Full Race exhaust manifold turbo of choice and custom exhaust made custom intake made and a rebuilt trans to handle the power.

csargemg

^^^

I always feel smart when Wrench agrees with me, haha.

Conclusion: I think Wrench best outlined the pathway. I only outlined the first stage, then abstracted.

wspy

So when you guys change the injector size, does this mess with the onboard fuel/range counter?

Can you get away with use/keeping the stock injectors if you only change the down pipe? And the intercooler to ETS?

ljcolomacks

Thanks for all the replies! Looks like I was pretty close to the right solution, but did not know about the transmission cooler or the ev14's. Heeltoe auto interestingly only showed the ev1's for the RDX, but maybe they just don't stock the ev-14's. Also good to know the stock fuel pump is sufficient.

csargemg

The EV14s are the Bosch-type injectors. They have 4 nozzles and far more precise spray patterns.

The Denso type injectors are older technology. They have two nozzles and are more random in their fuel delivery.

When you upgrade to bigger injectors, therefore, especially at lower pulse widths, the Denso type spray is more uneven and ragged. This leads to the ECU getting raggedy information back and forth and faster adjustments.

For the same reason, intakes that preserve as much as the stock system as possible leads to smoother airflow.

With smoother airflow and smoother delivery, you can reliably run a bit more timing. The smoothness is easily identifiable in datalogs.

I purchased my injectors off of VitViper's website.

KenB350z

That transmission tho.......

ExcelerateRep

You can change everything you originally listed without changing your injectors. Make sure you keep the car tuned for it's mods however; if you put a downpipe on a stock file it will most likely cause a CEL, the same would be possible from the cold air intake. Changing the injectors and trading up to a high pressure fuel pump definitely wouldn't hurt anyone; more power is always good!

Check us out for your performance needs! Excelerate's Honda & Acura Store - Japanese Performance Specialist - Homepage

If you don't see something listed you're looking for feel free to PM me, I'll help you find it!

Slow98teg

the stock injectors get maxed out with just a tune. No other mods. Cel won't pop up with a downpipe and stock tune as long as there's a defouler for the 2nd o2. Intake won't throw one either as long as the maf diameter is the same as stock. My downpipe and midpipe are still on with everything else stock. Been lazy to put the stock back on before i sell it.

wspy

Thanks Guys...

So if you were to change the injectors to larger ones....How will it affect the onboard fuel range display?

TheWrench116

iTrader: (1)

it becomes wrong... it will read high

Tomtwtwtw

I want to say you can specify the injector size within the Flashpro software to try and keep it accurate, but as Wrench mentioned, if nothing else changes the mpg indicator will read high. Higher flow injector = shorter injector pulse. If car things injectors are oem flow rate, it will report the shorter pulse as less fuel being used for any given situation.

wspy

Aah yes....ok Thanks guys.

7y123d

This is the first I've read where stock intake is better than an aftermarket one. I threw a 3.5" AEM filter on the end of the airbox. Is this about as good as it gets short of a custom intake?

ljcolomacks

I think the main reason is because with a lot of aftermarket air intakes, they draw air directly from under the hood next to the engine. After a while with heat soak from the engine, eventually you will be sucking in much hotter air vs the stock, which is drawing air from outside. They do make true aftermarket cold air intakes that use a big cone and are sealed off from the engine bay as well, but i have not seen one for the RDX.

Since you're still using the stock air box, you will still only have the same amount of airflow as the stock 3" housing does. That said unless you are able to decrease the air temp using the AEM filter, you will most likely not gain any power. Although you will hear your turbo much more!!

Really if you wanted to do better then the stock intake performance wise. You would most like like need to use a "3.5 maf housing" (TheWrench116) with a 3.5" intake as well. And best cause scenario you would use a true cold air intake as well. For the RDX you would have to customize one, most likely.

CSmoney28

I have a ton of parts on my vehicle with out a tune the only thing you need a tune for is injectors, fuel pump, or a turbo upgrade.