Hondata 05-06 RSX Type S Reflash
Part Number: K20Z1-05

Hondata 05-06 RSX Type S Reflash
    Some images may be for reference only

    Free Shipping
    Inside Continental United States


    Earn 580 reward points. Learn More

    Will It Fit Your Vehicle?


    The K20Z1 program advances the ignition, alters the cam timing and optimizes the fuel for better driving and advanced performance. It adds up to 20hp and up to 12 ft/lbs fo torque.

    This program works very well with cold air intakes and cat-back exhausts. If you have a race header then you need to use K-pro.

    This reflash is not suitable with stock air box, race header, anything other than stock cams, force induction or nitrous.


    You are responsible for paying for and sending your ECU to Hondata. You can send your ECU as fast as you would like and shipping costs normally start at $10.00 for ground and $60.00+ for next day air. We recommend using an express service (2 day or next day) through FedEx or UPS because they have the least amount of delivery problems, provide proper insurance, and have good package tracking. We recommend that you do not use USPS because of delivery issues. You are not sending your ECU to K Series Parts you will be sending it to Hondata directly and we provide all of the instructions on where it needs to be sent once your order is approved.


    After we approve your order we will send you two emails, one email will be a Hondata form and the other email will be instructions for shipping and what items need to be included. Orders submitted by 3:00pm Mountain Standard Time Monday to Friday are normally approved same day. Orders places after 3:00pm MST or on Saturday and Sunday are processed the next business day.

    Hondata normally reflashes ECU's the same day they receive them but they do get busy and it might take an extra business day. We recommend that you plan on a 3 day total turnaround time from the day that Hondata receives your ECU.

    Return Shipping

    Hondata uses K Series Parts FedEx account to next day air the ECU back to you once the reflash has been installed. This means that you do not have to pay for return shipping. Your ECU will arrive by 3:00pm the day after Hondata completes the reflash installation. Hondata does not provide us with a tracking number or notification when they ship the ECU back to you.

    ECU Serial Number

    The serial number is located on the ECU. Hondata has provided instructions on how to remove the ECU.

    International Customers

    K Series Parts cannot sell reflashes to customers outside of the United States per Hondata request. The shipping address must be a US based address.


    • 2005 US RSX Type S with K20Z1 engine - ECU part number PRB-A13
    • 2006 US RSX Type S with K20Z1 engine - ECU part number PRB-A14
    • 2006 US RSX Type S with K20Z1 engine - ECU part number PRB-A15


    • VTEC window from 4900 to 5800 rpm
    • 8600 rpm Rev limit, increased from 8300 rpm
    • Maximum torque gain 12 ft/lbs torque at 6000 rpm
    • Maximum power gain 20 hp at 8000 rpm
    • Peak torque increases by 6 ft-lbs
    • Peak power increases by 8 hp
    • Very wide flat smooth torque curve. 90% of peak torque available from 2200-8000 rpm.
    • Fully dealer compatible - works with all Honda scan tools and equipment


    Any increase in RPM limit is at your own risk. If you suffer engine damage that is related to excessive revs Honda / Acura will not cover your warranty.

    With regard to aftermarket parts, the law is that warranty coverage cannot be denied simply because such parts are present on the vehicle, or have been used. For more details read the K series FAQ.


    Honda may not cover mechanical damage to the engine under warranty resulting from exceeding the factory red line. Hondata & K Series Parts will not cover any damage as a result of installing this product.


    Brand: Hondata
    Part Number: K20Z1-05

    Vehicle Fitment

    Acura RSX

    25 reviews for Hondata 05-06 RSX Type S Reflash

    5 out of 55 out of 55 out of 55 out of 55 out of 5

    4.84 out of 5.0

    Add Your Review

    3 out of 53 out of 53 out of 53 out of 53 out of 5

    6/30/2012 by Kazumi Nomura

    All in all, okay

    This product is okay. It gives moderate gains. Engine sounds a little different, sounds a little deeper. It does make your car and acceleration smoother. I like the product, it's a nice gain, improvement. You really have to look for the difference, it's not easily apparant, noticable. Hopefully should be nice with some other improvements I plan to do.

    5 out of 55 out of 55 out of 55 out of 55 out of 5

    4/22/2012 by Dave

    Reflash fun

    2006 Type-S. Injen Ram air, Borla exhaust, and now the relash. Holy smokes. What a difference. Must have if you have no plans to turbo or supercharge. No need for me with these mods.

    5 out of 55 out of 55 out of 55 out of 55 out of 5

    4/17/2012 by Bthet

    Dee Shyytt

    I have an 06 with i/h/e and i know raceheaders are not recommended but ohhh welll :). Big difference in everyday driving which makes it more enjoyable and power gains are noticeable. Good upgrade for the price. Shipped it out monday afternoon got it back wednesday. Cant complain.

    5 out of 55 out of 55 out of 55 out of 55 out of 5

    3/25/2012 by IronGumby

    Feels like it grew to a 2.2L

    I cannot be happier with this mod!! It feels primed and ready for action at all times now. The new-found torque down low makes you wonder how you ever drove it before; it's hard to make it bog. VTEC now is enjoyed from 4900 on up and just really shines and makes one proud to have a K-motor. You can feel it surge a second time as you surpass 7000rpm, too! The higher revs are foreign to the ear and I feel like it finally broke my motor in. This is all with only the Icebox intake so I can only wonder what adding the CRSX header will do!

    5 out of 55 out of 55 out of 55 out of 55 out of 5

    2/13/2012 by Daniel Koffer

    Totally Worth It

    I got the reflash a few months ago because I didn't, and still dont plan to do anymore then basic bolt-ons. I already had a cai, and with the reflash, it is a night and day difference over stock. Worth every penny.

    5 out of 55 out of 55 out of 55 out of 55 out of 5

    9/29/2011 by edwin

    Great bang for your buck

    adds a nice increase in power over the stock ecu. no more huge surge in power after 6k rpm. its just way smoother over all

    5 out of 55 out of 55 out of 55 out of 55 out of 5

    4/12/2011 by Drew Ferraro

    worth the $

    brings a great kick

    5 out of 55 out of 55 out of 55 out of 55 out of 5

    4/10/2011 by Manuel


    Car feels very solid and smooth all the way to redline. Feels good not having to down shift to pass someone on the highway. Highly recommended if sticking with the basics.

    5 out of 55 out of 55 out of 55 out of 55 out of 5

    3/29/2011 by Gordon Fields II

    Friggin Awesome

    Best bang for your buck mod out there period. The lower vtec kick-in with the higher rev limit makes the power come sooner and the power band is smoother. Love it. Buy it now lol

    4 out of 54 out of 54 out of 54 out of 54 out of 5

    3/5/2011 by Henry Pan

    Keep your expectations reasonable

    Mods: Mugen Intake Box; 2.5" Exhaust Overall this was a fantastic mod. Before my RSX felt like it had a rubber band around its balls. The reflash has effectively removed the rubber band. The RSX makes noticeably more mid-range power now, vtec switch over is much smoother at WOT. The 8600 redline is quite nice, it opens up a whole new world for me. However, everything described seems like the RSX-S should have come stock like this. My idle is also at 2000 when I first turn on my car, (is this bad?)

    5 out of 55 out of 55 out of 55 out of 55 out of 5

    11/26/2010 by K. Potter

    Good mod for the $ - Really Works!

    Super fast turnaround with Hondata. Shipped on a Monday and got it back on Wednesday. This was a really good mod for the $. Very easy to do. The first time I tried it I noticed an immediate difference. Nice & smooth all the way through the power band. Don't have to wait till 6K for it to take off. If you have a CAI and good exhaust (which is what I have) then get this reflash, you won't be sorry. Glad I did it. If you plan on NOS or Turbo then get a K-Pro or AEM EMS.

    5 out of 55 out of 55 out of 55 out of 55 out of 5

    11/10/2010 by Henry R.

    Great addition to a great car

    The reflash does wonders. It makes everyday driving much more enjoyable. Like others have said, passing is much easier and more smoother power up top. I only only have the V2 intake in my car with Reflash and I love it. Great product, great service.

    5 out of 55 out of 55 out of 55 out of 55 out of 5

    10/18/2010 by Andrew Hill

    Reflash is worth it......

    Considering that K-Pro when said and done is between 1500-2000 bucks and reflash is only a fraction with the price drop. I would recomend this to anyone with basic bolt-ons, even a mild race-header. I would strongly suggest upgrading to K-Pro if you have, or before you get the rbc or any other intake. ClubRSX pulls through everytime.

    5 out of 55 out of 55 out of 55 out of 55 out of 5

    9/7/2010 by Neale O'Bannion

    Great bang for you buck

    Absolutely the best money I have spent on modifying any of my cars (including my EP, S2000, and my 3 Integras). This completely changed the vehicle in every way you can imagine. The mid range pick up is what I have enjoyed the most. Passing on the highway and normal everyday driving is much easier. There is no more massive rush of power at VTEC engagement. Itís just nice smooth power all the way to 8600 RPM. I would higly suggest this over any other modifications for the money.

    5 out of 55 out of 55 out of 55 out of 55 out of 5

    7/26/2010 by j.zachary

    good bang-for-the-buck mod

    the hondata reflash is the best bang for the buck mod ive gotten for my type s. i would reccomend it to any1 with a lightly modified rsx. great product. pretty big difference in low end torque & in VTEC power.

    5 out of 55 out of 55 out of 55 out of 55 out of 5

    5/29/2010 by Jay


    This tune should of been a stock base well with my mods( CAI,IMG,Shorty Header,Muffler) car FEELS stronger throughout the rpm range. The best power mod for under 3 bills.

    5 out of 55 out of 55 out of 55 out of 55 out of 5

    5/25/2010 by blynd99

    Reflash was long overdue

    Finally got the reflash and it is noticeably different. Very happy with the overall gains and feel. Have an Injen CAI and a Greddy SP2 exhaust.

    5 out of 55 out of 55 out of 55 out of 55 out of 5

    5/10/2010 by jorge rivas

    Must have upgrade

    I have a v2 aem intake with a borla catback and as soon as i did this reflash it was like both parts woke up... i did feel a difference with the boltons but hondata really helped plus the fact that the vtec kicks in earlier is even better... must have upgrade

    5 out of 55 out of 55 out of 55 out of 55 out of 5

    5/4/2010 by kojot1234

    Great upgrade

    Surely noticeable difference. Nothing huge but it definitely gives more kick, especially first two gears ;] Hondata received my ECU on Friday got my package back Monday morning. Worth the money!

    4 out of 54 out of 54 out of 54 out of 54 out of 5

    3/20/2010 by albert v.

    good. but was expecting a lil more

    more power than before. it is noticeable but not an amazingly big difference. definetly more power in vtec tho. no notice in mpg's might have lost 1 or 2. overall a good product and i did get stickers too :) might go k-pro next.

    5 out of 55 out of 55 out of 55 out of 55 out of 5

    12/4/2009 by Tim Zipfel

    K-series Reflash

    WOW! The best upgrade I have done so far. What a difference in performance it makes. I currently have the CRSX Injen intake along with a Borla Cat-back system. It really woke the car up. I have picked up lost .7ths in the quarter mile and gain 4 mph. Daily driving is greatly improved with the add torque below 3500rpm. VTEC transition is smoother. A must for a lightly modified build.

    5 out of 55 out of 55 out of 55 out of 55 out of 5

    11/26/2009 by valetser7

    Great fun.

    The powerband is so smooth after this install. No more waiting till 6k for some power. It's super easy to do and a very noticeable difference for not too much money.

    5 out of 55 out of 55 out of 55 out of 55 out of 5

    1/13/2009 by Martin

    Nice Power Boost

    It does what it claims. Higher revs are very nice. The torque starts alot lower and pulls really good all the way to redline! A must if you are sticking with basic bolt-ons. A good tide-over until K-Pro as well. Hondata ships it back as fast as you can get it to them! Highly recommended! =)

    5 out of 55 out of 55 out of 55 out of 55 out of 5

    10/29/2008 by Paulo ramos

    rsx s 06

    Its worth it. I just had my 06 rsx s ecu reflash and believe I felt the difference. The rev limit is now at 8600 rpm and the vtec kicks early at 4800 rpm when you really flour it. The shipment is extremely fast can wait to get it dyno to see the gains.

    5 out of 55 out of 55 out of 55 out of 55 out of 5

    7/18/2008 by bounthai rattanasith (vtak-20)

    06 Reflash

    Like alot of people will say it is the best bang for your buck wrapping it up to 8600 is very nice, and the low end torque was nice too, and with customer service like shipping and the instant email from crsx was excellent everything was quick and easy I only had to wait 2 full days for my ecu to come back!