Honda Civic Type-R (FK8/FL5)

There has been a lot of talk about our XDI-2000c injectors for the Type R. There is cold start issues and rough idle.

Hondata has published pictures of injector tips and corresponding spray videos, that show a bad competitor injector. People have been assuming, that “the competitor injector” is ours and that the idle issues come from the “bad spray pattern”.

We don’t know what injector they found and called “competitor injector”, but it’s for sure not ours. Please check out the pictures from Hondata and look at our injector. Our spray pattern is way different, even the tip shape and surface finish different. The “competitor injector” has a machined surface, ours is sinter material.

Now Regarding the Actual Design

We have tried the “dual center spray hole” design, that Hondata uses, at Bosch over ten years ago. It poses the risk of blown-off tip at high fuel pressures since it reduces the wall thickness in the injector tip too much. Especially with the counter bores for all holes. If I am ever bored enough to run an FEA analysis, I can explain that better.

For the spray pattern geeks, the counter bores reduce the L/D ratio (length over diameter) which leads to wider and shorter sprays (less chamber penetration). Not necessarily “better vaporization”. This is great for emissions and fuel air mixture with low air speed (low boost). When you add two spray holes in the center, both with small L/D, you add two short wide spray plums in the center. There will just never be any more air to mix with that fuel!

We at XDI have the outside holes with counter bores (small L/D) to fill the outside area of the combustion chamber w/o touching the cylinder walls. And a small diameter single center hole with bigger L/D and higher penetration, to reach the bottom side corner of the combustion chamber. Thats where a lot of air ends up with higher boost i.e. higher air speed. That air will create a local lean spot if you dont bring any fuel there.

So Why the Rough Idle?

Our injector is big. It flows 80% more than the stock injector! What Honda does from the factory, they run higher pressure on a small injector, to provide the right amount needed, but with maximized vaporization.

Now with an 80% larger injector, you get 80% more flow even at idle. Way too much. The ECU reduces the pulswidth to the injector to reduce volume at the stock pressure levels. Our injector, and almost every DI injector out there is highly non linear below 0.5msec. We recommend in our datasheet to never run less than 0.8msec. To get there you need to take the desired pressure down.

It took some time to find all the tables in the Honda ECU and get access. There is a hidden software function CVO, that occasionally sends the desired pressure up to 2900psi, at idle!!! Our 2000cc injector has to fire so short, that it barely opens at all. It runs rough.

Until somebody publishes emissions results or performance comparisons with identical engine parameters “Hondata 2000cc” vs “XDI-2000cc” and a clean calibration, that prove that the XDI spray pattern (of an actual XDI injector) is “garbage” and the Hondata spray pattern is superior, I call bullshit on all these accusations. The hate is only coming from these few pictures and some rough idle because the tuner didn’t take the rail pressure down and tried to run a 2000cc injector at idle at 2900psi because Honda needed that for better cold start emissions and the tuner didn’t know better yet.

Luke at 4 Piston made an incredible 911 bhp on his engine dyno utilizing our HPFP60 & 2500cc injectors.
The perfect paring for 1000bhp on the Civic Type R

• For our XDI-EVO, we highly recommend switching out that block on the “Hondata CANFlex Flex Fuel Kit”, especially if you see rail pressure drops after 5k RPM.
• As beautiful as it looks, it is not flow optimized.

• OEM: 200 bar / 2,900 psi
• XDI-EVO: 250 bar / 3,600 psi
• XDI-HPFP60: 260 bar / 3,800 psi

• Fuel Compatibility: All known fuels, all ethanol blends
• Electric Connector: Bosch Compact 2-pin
• Driver Profile: XDI, integrated in Hondata FlashPro
• Accessories: Electric pigtail, hardware
• Maximum Flow Rate: TBC (actual measured flow)
• Maximum RPM: 10,000 RPM (Tested on 4.0mm lobe)
• Housing Material: Stainless steel, hard coated aluminum
• Tuning Support: MoTeC, Hondata, WinOLS, Cobb
• Dry Weight: 1112 g