Turbo Base Model RSX Showcase

Base model RSX's often get the short end of the stick, but there are several brave car guys who tested themselves and their K20A3's, blazing a path of knowledge. Here's some compiled and cleaned up information, all in one place so you can get an idea what types of parts and setups are required to meet your boost goals on a base model RSX. I've included pictures and the usernames of the users from the forum I found them on if you want to pick through their setups anymore. A lot of these are quite dated, and technology has moved past some of the parts; I have a section at the bottom of the page that explains what we don't use anymore and why.

If you have a turbo base model RSX, please do reach out to me on my contact page and send me your pictures and full build sheet. I'd love to include it on my list to help newcomers make sense of putting together a turbo kit for this platform.

DC5slowww

DC5slowww's RSX Front End

200 horsepower | 213 lb-ft torque | 8 PSI

Setup:

• K-Pro
• K20A3
• Turbonetics T04B Turbocharger, .63 Exhaust and .70 Intake
• No Intercooler
• 550cc RC Injectors
• NGK Iridium BKR8EIX Spark Plugs
• Stock Base Intake Manifold
• 3" Turbo-Back Exhaust
• 2.5" Diameter Charge Pipe
• Revhard Top Mount Log Manifold
• TiAL 38mm Wastegate
• Greddy RS Clone BOV
• TurboXS Boost Controller
• Stealthmode Performance Oil Feed and Return Lines

309 horsepower | 274 lb-ft torque | 12 PSI

Changed Setup:

• eBay Intercooler
• PRB Intake Manifold (From RSX Type-S)
• 3-Bar MAP Sensor

348 horsepower | 309 lb-ft torque | 17 PSI

Engine Blew At This Power Level

Changed Setup:

• Clutch Masters FX300 Clutch
• RSX Type-S Flywheel
• Precision 1000cc Injectors
• Walbro 255 LPH Fuel Pump
• Golden Eagle Fuel Rail (Optional)
• Golden Eagle Oil Filter Sandwich Plate (Optional)
• Autometer Oil Pressure Gauge (Optional)

Build Breakdown:

There's no dyno graphs I can find for this one, but the numbers make senses and DC5slowww is a trusted community member. This was the highest horsepower documented base model RSX. Even more impressive, the owner maintained a stock K20A3. Unfortunately in the last stage of the project at the highest horsepower numbers, the engine gave up and he sold off the undamaged parts. I'm not sure exactly which straw broke the camels back here, but I'd guess that upgrading the pistons, rods, and rod bolts would have provided some more stability to the build. Altogether, an awesome project on a reasonable budget.

aftershock141

aftershock141's RSX Front End

aftershock141's RSX Engine Bay

aftershock141's Dyno Graph

305 horsepower | 281 lb-ft torque | 14.5 PSI

Setup:

• K-Pro
• K20A3
• Garrett GT28RS Turbocharger .86 AR
• HKS Downward-Facing Cast Log Manifold
• Thermal 3" Catback Exhaust
• Hondata Intake Manifold Gasket
• PRC Intake Manifold (From RSX Type-R) with R-CREW P.I.M.P. Plenum Expander
• RSX Type-S Throttle Body
• Kinetic Large Front Mount Intercooler
• 2.5" Intercooler Piping
• Fast-Turbo Oil Feed and Return Lines
• Walbro 255 LPH Fuel Pump
• Apexi AVC-R Boost Controller
• Apexi Turbo Timer
• 650cc RC Injectors
• AEM 3.5-Bar MAP Sensor
• AEM Vacuum Manifold
• AEM IAT Sensor
• Custom Oil Filter Relocation Kit
• HKS SSQV BOV

Build Breakdown:

This is the second highest horsepower documented turbo base model RSX that I could find (wow, mouthful). Another really cool build made with great parts. The owner stated that he likes doing things right the first time, and it shows in the quality, power, and longevity of his build. There's a kind of funny piece of history here with the P.I.M.P. plenum expander. There were arguments all over the forums when it was released about if it actually increased horsepower or not. It was a chamber that added volume to the intake manifold. It's my belief that it didn't necessarily improve horsepower too much in a noticeable way for a daily driver, but it did improve throttle response. The expander allows more air to be ingested into the engine at once on short notice. This technique has been used in restrictor plate racing to allow better on throttle response.

JMTweer

JMTweer's RSX Dyno Graph (Top Line is Boost, Bottom is Horsepower)

228 horsepower | ~180 lb-ft torque | 8.5 PSI

Setup:

• K-Pro
• K20A3
• Greddy Turbo (Kit)
• PRC Intake Manifold (From RSX Type-R)
• HKS Cat-Back Exhaust
• Walbro 255 LPH Fuel Pump
• 2.5" Intercooler Piping
• RSX Type-S Throttle Body

Build Breakdown:

This is a pretty basic turbo base model RSX build. Not as much information about it as some of the others out there, but it still serves as a data point. 

The Greddy turbo kit used to be a staple in the RSX world. It was a low boost 8-10 PSI setup that came with a lot of the important things you needed to get your K-series engine boosted.

jroc04si (EP3 Civic with K24A1 Head)

312 horsepower | 257 lb-ft torque

Setup:

• K-Pro
• K20A3 Block
• K24A1 Head
• Precision SC6152E Turbo
• Cybernation Turbo Kit
• Cybernation Exhaust Manifold
• 2.5" Turbo-Back Exhuast
• PRC Intake Manifold (From RSX Type-R)
• Maxbore Throttle Body
• 2.25" Intercooler Piping
• Turbo XS Boost Controller
• Greddy Turbo Timer
• TiAl Wastegate
• Vortech BOV
• GM Boost Solenoid
• RSX Base 5-Speed Manual Transmission
• Stock Flywheel

Build Breakdown:

So this might be cheating a little bit, but it's still a K20A3, it's just in an EP3 Civic. He also did swap the head for one off of a Honda CRV between 2002 and 2006. It does not include true VTEC, but the head flows similarly to the K20A2 (RSX Type-S) head. A better flowing head can reduce the amount of boost required to make the same amount of power. He did break 2nd gear in his transmission on this setup, and replaced it with an RSX 5-speed transmission inside the EP3 transmission case. Additionally, it's worth mentioning it started out as a Cybernation turbo kit, but the shaft play on the eBay-quality turbocharger was too much for him to run it confidently and ended up buying a separate compatible turbo from a more reputable manufacturer.

RyanRSX

RyanRSX's Dyno Graph

303 horsepower | 267 lb-ft torque | 13 PSI

Setup:

• K-Pro
• K20A3
• Cybernation Turbo Kit
• Bosch 1000cc Injectors
• Walbro 255 LPH Fuel Pump
• Turbonetics Evolution Wastegate

Build Breakdown:

Not a ton of information on this one, but we can see some common themes here with the 255 LPH fuel pump, 1000cc injectors, and K-Pro coming together to create a formidible base model RSX.

JJMc1025

280 horsepower | 275 lb-ft torque | Unknown PSI

Setup:

• K-Pro
• K20A3
• Greddy T51Z Turbo
• Greddy Exhaust Manifold (From Turbo Kit)
• PRC Intake Manifold (From RSX Type-R)
• Treadstone Intercooler
• HKS SSQV BOV
• 440cc RC Injectors
• Walbro 255 LPH Fuel Pump
• AEM Fuel Rail
• RSX Type-S Throttle Body (Bored Out)
• Blitz Turbo Timer
• Fuel Pressure Regulator
• Return Fuel System
• Fast-Turbo Oil Feed and Return Lines

Build Breakdown:

This user follows a lot of the same patterns in the previous builds we've looked at. At this power level he actually snapped an axle. I believe he didn't make more power due to injector choice.

crazy-yogi

297 horsepower | 260 lb-ft | 17 PSI

Setup:

• K-Pro
• K20A3
• Precision SC3427 Turbo
• HKS SSQV BOV
• TiAl 38mm Wastegate
• 750cc RC Injectors
• Treadstone Intercooler
• Treadstone Exhaust Manifold
• 3" Turbo-Back Exhaust
• RBC Intake Manifold (From 2006-2011 Civic Si)
• RSX Type-S Throttle Body
• Competition Clutch Stage 4 Clutch
• RSX Type-S Flywheel

Build Breakdown:

This is a cool build that made good power with plenty of ingredients from our proven formula that's been building. Strangely the first one I've seen that uses the current standard clutch for high-horsepower builds, the Competition Clutches Stage 4 Clutch.

03DSM-RSX (Automatic Trans)

03DSM-RSX's RSX Front End

03DSM-RSX's Final Dyno Graph

224 horsepower | 200 lb-ft torque | 10 PSI

Setup:

• K-Pro
• K20A3
• Greddy Turbo
• Greddy Exhaust Manifold
• Greddy Downpipe
• Turbo XS Boost Controller
• HKS SSQV BOV
• Custom Front Mount Intercooler

256 horsepower | 222 lb-ft torque | 12 PSI

Changed Setup:

• PRB Intake Manifold (From RSX Type-S)
• RSX Type-S Throttle Body
• GM 3-Bar MAP Sensor

Build Breakdown:

This is a particularly interesting build. Put together by the user and popular tuner, st00pid, this build uses 2 ECU's. The stock base ECU is only used for the transmission control. A PND RSX base manual ECU is used to make the tuning magic happen. The owner started off with SAFC2, a piggyback ECU setup, but found out it's not a great solution for making reliable power and having full control of the car. With a fairly humble buildsheet, the owner made decent horsepower for a base model, but that wasn't enough. He came back with some upgrades to the intake system and made another 30 horsepower and 20 lb-ft of torque. Adding the MAP sensor wired directly to the base model auto ECU corrected the shifting under boost and helped idle significantly. If that wasn't enough, they also added a dual stage boost controller, allowing a boost cut at high RPM to give the transmission a break from the power. 

Additionally, 03DSM-RSX did a writeup on mods for automatic transmissions that's incredible, check it out here.

yeahi (Automatic Trans)

240 horsepower | 204 lb-ft torque | 10 PSI

Setup:

• Apexi SAFC-2 FMU
• K20A3
• Cybernation Stage 1 Turbo Kit
• Turbo XS BOV

Build Breakdown:

The car was totalled unfortunately it seems. There's not much info about it, but it just stands as another example of an automatic transmission base RSX getting a turbo kit and making power.

45

270 horsepower | 245 lb-ft torque | 16 PSI

Setup:

• K-Pro
• K20A3
• Precision SC34 Turbo
• RC 750cc Injectors
• 3" Turbo-Back Exhaust
• MSD 3-Bar MAP Sensor
• HKS SSQV BOV
• RBC Intake Manifold (From 2006-2011 Civic Si)
• Greddy Turbo Timer
• RSX Type-S Throttle Body
• Turbo XS Boost Controller
• GM Boost Solenoid
• TiAl 38mm Wastegate
• TD Autowerkes Stainless Steel Top Mount Manifold
• TD Autowerkes Oil Feed and Return Lines
• Greddy Front Mount Intercooler

Build Breakdown:

The car was either parted out or sold. The account associated with it doesn't have much of a history beyond almost immediately selling the car and buying a Honda S2000.

supradriver08 (Automatic Trans)

270 horsepower | ~230 lb-ft torque | 16 PSI (93 Octane) (Automatic)

280 horsepower | ~240 lb-ft torque | 13 PSI (93 Octane) (Manual)

315 horsepower | ~280 lb-ft torque | 14 PSI (On E-85) (Manual)

Setup:

• K-Pro
• K20A3
• Greddy Turbo Kit
• 2.75" Turbo-Back Exhaust
• E-85 Fuel System
• ID 1000cc Injector
• Turbo XS BOV
• RSX Type-S Throttle Body
• RBC Intake Manifold (From 2006-2011 Civic Si)
• Walbro 255 LPH Fuel Pump
• Hondata 4-Bar MAP Sensor
• Greddy Profec B-Spec Boost Controller

Build Breakdown:

This build was interesting to me because it was converted from a base model automatic transmission turbo build to a base model manual transmission turbo build, and then the owner added E-85 to spice it up further. They started out with the dual ECU setup, like the one mentioned above in 03DSM-RSX's build. Finally we see some more modern injectors, the ID 1000's that have made their home in many turbo builds.

The setup mentioned above seemed to be consistent through all of the different stages in the build, the only thing that changed was fuel and transmission.The owner does mention with the automatic that a transmission cooler and high stall torque converter can make repeated pulls much more reliably. Once he installed it, he mentioned that it keeps making consistent power and pulls more smoothly.

mockerblah!

mockerblah!'s RSX Front End

mockerblah!'s RSX Dyno Graph

477 horsepower | 342 lb-ft torque | 16.5 PSI

Setup:

• K-Pro
• K20A3
• 4-Bar MAP Sensor
• K20A2 Crankshaft
• 9:1 JE Pistons 86.5mm
• Eagle Rods
• ACI Coated Main Bearings
• 1000cc Injectors
• Walbro 255 LPH Fuel Pump (In Tank)
• Walbro 255 LPH Fuel Pump (In Fuel Line)
• AEM Fuel Rail
• RBC Intake Manifold (From 06-11 Civic Si)
• K20A2 Throttle Body (From RSX Type-S)
• BC Valve Springs
• BC Forced Intro Camshafts
• Peakboost GT3076R Turbo Kit
• Moroso Oil Catch Can
• Competition Clutch Stage 4 Clutch
• Limited Slip Differential (LSD)
• 3" Turbo-Back Exhaust
• Albins Synchro Engagement Helical Gear Set 1-4

Build Breakdown:

Big power costs big money, and that's present here most of all. Since K20A3 crankshafts aren't balanced like the K20A2, that's a limiting factor. Also, not as many manufacturers offer performance engine parts for the K20A3, like rods. This owner decided to swap the crankshaft to get a better balanced crankshaft for higher RPM operation, and access to Eagle rods. He also spent some big money on building the transmission in his base model, since the gears are going to be a big point of failure with high horsepower and torque. The Albins gear set costs about $4,000, so it's a fairly serious investment. I like the catch can, that's important in boosted setups to deal with moisture and excess oil vapor pressure in the valve cover. The LSD is a necessity for any boosted or high horsepower NA RSX to put the power to the ground instead of spinning wheels. There's a video of this car running from 2012 and revving to probably 8,500 RPM which is absolutely insane for a K20A3. Here's one of it on the dyno.

Now, do I suggest you do this? Absolutely not. It's much cheaper to buy a K24 and swap it in and turbocharge the stock engine, and it will be more reliable and have room for more boost in the future. However, I do think it's a very cool build that shows the capability of the K20A3 platform if you really need to make it work. It's absolutely not easy(ish) / cheap(ish) power like you can sneak away with on the K20A2 from the RSX Type-S or a K24A2 from the TSX.

DC5808

DC5808's RSX Front End

271 horsepower | 244 lb-ft torque | 15 PSI

Setup:

• K-Pro
• K20A3 (Bored to 86.5mm)
• K24A1 Head (From Honda CRV)
• Greddy T51Z Turbo Kit
• RBC Intake Manifold (From 06-11 Civic Si)
• Hondata Intake Manifold Gasket
• 05-06 RSX Type-S Exhaust
• RSX Type-S Throttle Body
• RSX Type-S Camshafts
• RSX Type-S Rocker Assemblies
• Stock Fuel Pump
• Siemens 650cc Injectors
• Greddy Front Mount Intercooler
• EVAP Delete

*Never Finished Documenting Power, But Built For 600 Horsepower Goal*

Changed Setup

• Bosch 044 Fuel Pump (In Line)
• Walbro 255 LPH Fuel Pump (In Tank)
• E-85 Fuel
• Mishimoto Radiator + Mishimoto Radiator Fans
• Treadstone Front Mount Intercooler
• PPG Straight Cut Gears 1-4
• Base 5-Speed Manual Transmission 4.3 FD Ratio
• Gearspeed Carbon Gear Synchros
• M-Factory Limited Slip Differential (LSD)
• -8 AN Fuel Feed Line
• Aeromotive A1000 Fuel Pressure Regulator
• BDL Fuel Rail
• Inline Fuel Filter
• Fuel Injector Clinic 2150cc Injectors
• Competition Clutch Twin Disk
• Peakboost Sidewinder Turbo Kit
• Precision 6265 Billet Journal Bearing Turbocharger
• TiAl 44mm Wastegate
• TiAl 50mm BOV
• 3" Turbo-Back Exhaust
• CRV Exhaust Rockers "Newer Style"
• Supertech Dual Valve Springs (100 PSI)
• Supertech Steel Retainers
• Supertech Valve Keepers
• Supertech Steel Valve Seats
• Supertech Inconel Exhaust Valves
• Supertech Inconel Intake Valves
• OEM Valve Seals
• Prayoonto Billet Stage 2 Camshafts
• Golden Eagle Head Studs
• NGK BKR9EIX Spark Plugs
• Corsport VTEC Solenoid Delete Kit
• Custom Oil Cooler
• OEM Head Gasket
• Ported K20A2 Oil Pump
• Brian Crower Pro Series Connecting Rods
• ARP 625+ Rod Bolts
• Spuntek Lower Timing Chain Guide

Build Breakdown:

This is much like the build above, but goes so much further down the rabbit hole. The owner started off with a base model RSX and did a "VTEC Killer" setup, which involves blocking off the VTEC solenoid. In a setup like this, there is no VTEC switchover, you're always running on the larger performance camshaft lobe profile. It's not great for low end engine torque, but it's meant for high end horsepower at the top of the rev range. It lowers the weight of the camshaft and can be kind of hard to get a consistent idle since the valves are opening so far. It can kind of sound like the lope from a big cam V8. With a stock K20A3, VTEC killer cams, and E-85, with a 3" exhaust, that's already a formula for some big power. There's evidence of NA builds making 200 horsepower on that setup. 

This owner used the common Greddy turbo kit to boost his setup in its first iteration, but throughout upgrading towards the goal of 600 horsepower made the move to a sidewinder manifold and a GT3076R. This is a known recipe for strong high horsepower RSX's. He augmented it with a full engine build, and stronger transmission gears and synchros to be able to hold all that power. This is a really amazing build and shows that you can do a lot with the K20A3. This type of build would be ideal for a drag racing setup because if you break the block or head, it's super cheap to get a new one since everyone wants the K20A2, not the A3. However, if you plan on making a daily driver, this amount of power doesn't make sense for a K20A3 because the head doesn't flow very well and the crankshaft isn't balanced as well as the K20A2 shaft.

Redline10000

302 horsepower | 268 lb-ft torque | 14.5 PSI

Setup:

• K-Pro
• K20A3
• Garrett GT2871R Turbo
• Revhard Exhaust Manifold
• TiAl 38mm Wastegate
• GM Boost Solenoid
• Greddy Front Mount Intercooler
• RC 750cc Injectors
• HKS SSQV BOV
• NGK BKR8EIX Spark Plugs
• 3" Turbo-Back Exhaust
• RBC Intake Manifold (From 06-11 Civic Si)
• K20A2 Throttle Body

Build Breakdown:

There's not a ton of information about this one, but the owner made good horsepower and used the right stuff. The GT2871R is a great size turbo for RSX's to make reasonable amounts of power without getting too crazy. It seem to me like the NGK spark plugs in this heat range are pretty standard on these turbo builds, even if they're not mentioned by name. I believe they're the stock plugs, but I'm not sure if you can gap the stock plugs smaller without a special tool since they're iridium. Altogether, great formula. The car seems to have been returned to stock and sold.

Conclusions

Wow, after going through and scouring for all the information I could come up with, there was a lot of cool things to learn here. Many of these setups have a lot of similarities, but one of the key features I've noticed is the lower horsepower builds are usually just missing one or two higher quality parts that they need to make more power, or make more consistent power across the rev range, most often the RBC intake manifold or bigger / better injectors.

Additionally, there were a lot of technologies that have changed that I feel the need to talk about. A lot happens in 20 years, and it can be confusing going to Google to figure them out only to find nothing there.

Unfortunately for the automatic base RSX drivers, there were 2 suppliers for the harness that's required to use K-Pro. Someone on the forum named "Joel", and a wiring harness manufacturing company, Boomslang. Both of them do not sell these harnesses anymore that I can tell.

APEXi SAFC-2

The Apexi SAFC-2 was a piggyback tuning device that allowed fuel control based on intake air readings. It was used in some of the builds I mentioned to cope with the fact that Base Automatic RSX's couldn't use K-Pro with their ECU's. It's basically a Fuel Management Unit (FMU), and as such, doesn't allow complete control over all the factors you'd want as a tuner. K-Pro basically came and blew it out of the water.

RC fuel injectors still exist, but they've fallen out of favor in the community, to put it bluntly. RC injectors were designed in the 1980's and sold through the early 2000's. However, with Bosch's release of the EV-14 standard, it became possible to get better flow characteristics from bigger injectors at lower flow rates, offering better daily drivability and better fuel atomization for more power. Now you can get the Injector Dynamics, Injector Clinic, and many other brands based off the Bosch design.

Walbro doesn't "technically" exist under the same name anymore, but the name is so popular they continue using it despite changing the name to TI Automotive. While this used to be the standard, now I don't see a reason to not run the AEM 340 LPH E-85 pump. It's definitely a strong pump, I use it, and it flows perfectly fine and holds up to E-85 which is more common now in more places. Boosted RSX's are a great place to use E-85 as well since it has a cooling effect on the charge.

Cybernation's RSX Type-S Offerings

Cybernation Motorsports doesn't exist anymore, and their turbo kits are a relic, albeit an important one of the past. They were popular before K-Pro was created, and used with ECU piggyback devices. The kits did circulate for a while and were used with K-Pro after their prime. Honestly, they had a bunch of problems with cracking manifolds, bad intercooler piping fitment, bad customer service, prehistoric engine management, and more. However, their sales pitch was interesting for sure. From 2007, these were their product offerings (for the Type-S):

Greddy RSX Turbo Kit

Greddy still exists, but the turbo kit made for the 2002-2004 Acura RSX base and Type-S is long discontinued. $4,000 got you a pretty cool little kit that made waves in the RSX turbo scene for years.

Note: There's a lot of builds that I haven't documented in here yet, and maybe information I haven't found yet. Pictures from this era are a bit harder to come by since the image hosting companies that were popular then are defunct, or accounts have been deleted. I'll be adding any others I find in my travels through build logs. I still do have some organization to do on here, but since it'll grow with time, I'm publishing in its current state.