Injector choices

blackcloudCTD95

New member
I'm looking to change up my set up and get rid of some of the fuel I have. I was looking at going to a 5x12 with the correct spray pattern but then I found 5x13 6x12 7x12 are they all equal to a 5x12? But atomize better? I haven't bought a set of injectors in years who should I go with dap ddp or ducky ? I'm open to other options also
 
That's what I have now I'm looking to go down in fuel. I'm just wondering if the above injectors I mentioned flow the same amount of fuel that a standard 5x12 does .
 
to answer your original question, NO they are not equal to 5x12's. if you change keep 5 hole injectors in your truck. that's what it is designed for. that said, why not play around and get those 14's working well. they aren't over sized. if you are running all 425CC's at WOT that's a problem as you wont be able to burn it all.

if you want 525hp and make 1.6hp per CC of fuel you only need 328cc's theoretically to do this. at 1.4hp per cc that 375cc's.

ide loose 3-5* timing
install smaller delivery valves (speed up the injection)
and give that AFC a good tuning before ide change injectors.

clean power has a lot more to do with delivery rate than quantity of potential injected fuel.
 
Just for reference, here's the area of the holes in the following injectors in in^2 and the percentace change compared to your current 5x14's:
5x12 - - - 0.000005655 - - - 73%
5x13 - - - 0.000006637 - - - 86%
6x12 - - - 0.000006786 - - - 88%
5x14 - - - 0.000007697 - - - 100%
7x12 - - - 0.000007917 - - - 103%

Timing will need to b adjusted based on spray pattern, but if your pattern matched your piston bowl, then I think 21-23deg is where I'd set timing for the sxe366 running 4k gov springs. Make sure you're keeping fuel pressure up past 3,000 RPM still (if not, address that), and I also second moving away from the 191's. Those 7mm DV's are pretty nice for a street truck!
 
his 366 is his primary in a small towing set-up... its not a big single

I know, but a 366 isn't a huge charger, it's not drastically larger than an HX35, and I'd spec my fuel assuming he's got a large enough wastegate on that HX35 to make it 90% transparent in higher RPMs. Adjusting to a different spring in the AFC/some tuning could make it tame enough at low RPMs. :Cheer:
 
The reason I am changing the injectors is because I want the proper spray pattern and get rid of the haze. I was given these injectors to use while my 5x12 were getting freshened up. ( when I did the head gasket) and I got lazy and never swaped them out then sold them.

Ive tried many different AFC Springs I played with the placement of the housing and the pre boost fueling. I got it as best I could as far as street maners go. The truck is at 22-23* I was going to go back down to 19-20* if I went back to a 5x12 .
 
Last edited:
Well, with marine injectors, you can't run as high of timing (at least until ~3000+ rpm) because you're shooting way outside the bowl. I bet switching to any similar sized 145deg spray pattern is going to give you much better street manors. I'd do 145deg spray 7x11 or 7x12 injectors, and a better set of delivery valves. Then start messing with the AFC spring and tuning. I bet you'll be really happy with the setup.
I'd leave timing at 21-23deg as well.
 
Well, with marine injectors, you can't run as high of timing (at least until ~3000+ rpm) because you're shooting way outside the bowl. I bet switching to any similar sized 145deg spray pattern is going to give you much better street manors. I'd do 145deg spray 7x11 or 7x12 injectors, and a better set of delivery valves. Then start messing with the AFC spring and tuning. I bet you'll be really happy with the setup.
I'd leave timing at 21-23deg as well.

Vco or sac? I forget what my current 5x14s are. I know they are from ddp. Some where further up in the post someone said to stick to 5x because that's what it was designed for?! I guess anything would be better than 191 s ill see if I dont have my old 181s laying around to try it.
 
SAC wit a small nozzle hole. is my preference. your 12 valve was designed with 5 hole injectors at 145* spray pattern. a 7 hole injector was originally 24v stuff. you can read in between all the lines of hocus pockus about better spray pattern and what not from the 7 holers in an old truck. my personal experience will vary from the next guys so take it all with a grain of salt. but 7 hole injectors are dirty POS's compared to their properly sized 5 hole cousins. shoot me a PM with your phone number and I can send you some videos with some proof and injector sizes.
 
No offense to anyone trying to offer help here, but if you have DFI injectors then call Chris and talk with him about how to solve your issue.

I'm pulling my 5x14's 155* this weekend to send back to him and upgrading to 5x18's he's treating me very well as he always does!
 
No offense to anyone trying to offer help here, but if you have DFI injectors then call Chris and talk with him about how to solve your issue.

I'm pulling my 5x14's 155* this weekend to send back to him and upgrading to 5x18's he's treating me very well as he always does!

I second that opinion, great guy.
 
I always found the 155° spray angle spooled the charger earlier and ran pretty clean. Over the 145's and stock pistons. 20° timing wasn't a problem.
 
Using 155's without the marine pistons, you're asking for trouble. Cheap to buy, buy why would you want to spray outside the bowl with the additional 10*? To each his own. Sure it'll run ok for a while, but doubt it's good long term.
 
Using 155's without the marine pistons, you're asking for trouble. Cheap to buy, buy why would you want to spray outside the bowl with the additional 10*? To each his own. Sure it'll run ok for a while, but doubt it's good long term.

I have Mahle big bowls :evil
 
Back
Top