Modifying injectors to flow more ..

[Radicalblackcivic]

stock are 310cc

[Pir8pete]

Originally Posted by Radicalblackcivic

stock are 310cc

sweet thx that's good news for us bad for ct-e lol well for the ppl that are good with there hands

[Radicalblackcivic]

ya, thats why i was wondering if i did that to my 370cc inj if there would be more flow... like it says, 270 to 480 and 310 to like 520... looks like it adds 200.... so 570 to the 370?

[vtecmike1]

Originally Posted by Radicalblackcivic

ya the 550 inj didnt make much diff. i was trying to run abit more boost and the maxed out right away. what do people use then in their kseries ?

its not the fact 550cc's aren't enough. its the fact that the spray pattern for RC 550's in k series are known to just flat out suck. they max out well before they should. the honda modified 520's will flow and not max out when running 9psi supercharged yet the 550 rc's will have lean spots in the upper rpms due to the y spray pattern.
i don't know if your 370cc injectors can be modded like a stock injector. i could be wrong though. but i have a feeling the modified 520's might be enough for you.

[Radicalblackcivic]

ya you are right man. im running around 11psi on my setup...and around 4k rpm they are at all they can give.... then after that its normal... but ya they max out at 4-5rpm then after vtec it richens out normal.... i dont understand why... im around 300whp and 257torque... i just dont like to have my inj. mex out at that point right before vtec... i was thinking about just upgrading to bigger inj... and leavin the same set up

[vtecmike1]

since your turbo.. i'd go with either rc 650cc injectors or the modified honda 520's.
the rc 650's have 0 issues. they run great. in fact since you are turbo's i'd prob recommend the RC 650's. they are expensive but wonderful and leave you room to improve. should be a nice low duty cycle for you as well. if and when you decide to go past 300whp and go for more. a walbro fuel pump and the 650's would let you do it.

ninja edit: whatever route you decide. different injectors should require a new tune.

Hondata wrote:

"There have been some reports of misfires and lean areas at high RPMs with JR superchargers for the RSX.

These problems all seem to be mostly associated with:

- 550 Injectors

Here is my opinion.

When testing the European Civic Type R supercharger we found a regular misfire would occur at a set RPM. This misfire would occur at the same RPM every time.

To cut a very long story short - after several months we found the misfire was the result of the combination of:

- The spray pattern of the 550 injectors
- The position of the 550 injector
- The speed of the blower (related to pulley size)
- The angle of the camshaft (VTC)

Altering any of these would alter the RPM at which the misfire would occur. We surmise that the fuel from the fuel injector was being blown backwards and (possibly) into another cylinder. We know the fuel is blown backwards as we have seen nice circular clean spots on the back of the JR manifold. Reversion also happens in NA engines. This is not unusual.

The fuel we suspect is being blown the wrong way as a result of the pulses coming from the blower at a particular speed interacting with the reversion pulses from the cylinder.

The easiest solution was to run 650 injectors which have a more diffuse spray pattern and inject the fuel over a shorter time period.

It would appear that a switch to 650 or 750 injectors will solve the problem. We would also suggest a fuel pump upgrade if you are nearing 300hp."

i suspect they don't work too well with turbos either.

hope i could be of some help.

[ryanmcm83]

Interesting info. Thanks for digging this up everyone.
You all just saved me $300 bucks that can go toward a good 300whp tune and a 255lph fuel pump!

[Radicalblackcivic]

ya i got my pump in whining... hehehe the walbro.. but ya i might update the injectors later.. for now i turned down abit the boost... 290 whp is still beats for the streets... and inj. are not going 100 percent duty cycle...

[FDcivic23]

When modifying the injectors, I read that to be on the safe side, they recommend sending your injectors to get cleaned and tested by a company like RC. Costs about $115 shipped both ways. After performing the modification, theres no telling the reliablility of the job. But all in all, you'd still be saving about $300 from buying the 520cc injectors that CT modifies the same way.

BTW I heard if you upgrade the fuel pump to a high flow, that our cars require a fuel return system.

[Supa Ninja]

Originally Posted by FDcivic23

When modifying the injectors, I read that to be on the safe side, they recommend sending your injectors to get cleaned and tested by a company like RC. Costs about $115 shipped both ways. After performing the modification, theres no telling the reliablility of the job. But all in all, you'd still be saving about $300 from buying the 520cc injectors that CT modifies the same way.

BTW I heard if you upgrade the fuel pump to a high flow, that our cars require a fuel return system.

its highly recommended but not required. its on the to do list for my car though.

[Swift Racing Technologies]

This actually got me very curious.

So I decided to do some of my own testing to see what was actually going on instead of taking the word of anyone else.

IMO. After observing a stock injector and a modified injector it is highly NOT recommended to do so. Here is why: The spray pattern of the factory injector is amazing as far as fuel atomization is concerned. On the modified injector there is no such thing as spray pattern it is simply like a fire hose.

The factory injector is 340cc/min and the modified one is 580cc/min @ 43.5PSI

I have attached some pics for you all to enjoy.

Spray Pattern! What Spray Pattern?
Factory injector on left and modified factory injector on right:



Look at the way the modified one fires like a fire hose, on a pulsed injection mode @ 1000 RPM there are literally big droplets coming out the modified injector.

[skinsfn36]

^wow, great testing

[Swift Racing Technologies]

Originally Posted by skinsfn36

^wow, great testing

Thank you sir,
I actually like to do my own testing as there is so much misinformation on the net.

[civicsifg2]

hmm yeah makes me not know if i wanna get the SC upgrade and use these fire hoses in my car

[vtecmike1]

you did it wrong. CT injectors only run 520cc not 580 and theirs still retain a spray pattern.
not to mention this has been proven to work for ALMOST 10 YEARS with rsx's already.
this is nothing new.

IF the real things sprayed like that. the cars wouldn't run right. it simply wouldn't work. you can't spray fuel like the injectors you have. the car might not even run.

[skinsfn36]

Originally Posted by Swift Racing Technologies

Thank you sir,
I actually like to do my own testing as there is so much misinformation on the net.

Originally Posted by vtecmike1

you did it wrong. CT injectors only run 520cc not 580 and theirs still retain a spray pattern.
not to mention this has been proven to work for ALMOST 10 YEARS with rsx's already.
this is nothing new.

IF the real things sprayed like that. the cars wouldn't run right. it simply wouldn't work. you can't spray fuel like the injectors you have. the car might not even run.

Swift, you should see if you can get a hold of one of the modified ones from CT or get somebody nearby to lend you one for an hour and run another side-by-side like this.

[FDcivic23]

I'm highly interested in seeing this.

[Supa Ninja]

I heart my Pecision 525's

[HONDACARE]

LOL @ the propaganda of SRT. are they not letting you become sponsors?

(buy our new turbo kit not that other new fi kit that uses these)

misinformation,

[Radicalblackcivic]

ninja, so u like ur precision inj? i might get the 650cc in here for sale if the guy ever replies back