Need input here on injectors

[MrOneEyedBoh]

So I'm still on the fence about which way to go with my build. Im stuck on injectors for a few reasons. First off I don't tow at all, so that opens more options.

The injectors I was looking at are 175/75-190/30-50s.

My concerns are: would I be able to hold ICP on the 190s? ( I know 175s would be no problem )

What about FP with only a RR? I don't want to have to get a fuel system for the truck.

Lastly will be turbo size. Barder can bore out my 03 for around 900. Would that be enough air on the 175/75? I know it wouldn't work for the 190s. Or I can go to a kc68 or a barder 68 and that would be more than enough on both sized injectors.

I do DD this but only for another year or so. I also accept the fact that the trans might sh!t the bed as well, although I'm a fairly sensible driver.

Power wise I'd like to be around 550-600. I plan on running a ported intake, ficm tunes and Gearheads tunes. Plus a RR and larger turbo as seen above. I came across a thread talking about stock intercoolers leaking, how prevalent is that?

 

[mind if I smoke]

Just my .02. To get to 600 you will probably need to go to the 68mm. I have 180/75 and have no problem holding ICP. As long as you have the R&R I would think you would be able to hold fuel pressure for 190s. With the setup in my sig I put down 565 at dyno proven's open house with no meth. My track times estimate me at 530-540. And as far as intercooler goes, from what I have been reading the factory can hold, its just a matter of time and luck. Plenty of guys have killed factory intercoolers with stock turbos and powermaxs.

 

[Pizza pig]

Do you have a fuel pressure gauge? I hate to burst your bubble but, most trucks I see tune only cant maintain proper fuel pressure with the stock fuel system even with the blue spring and a new factory pump. Probably going to need more than just a regulated return, the stock pump just doesn't have the volume in most cases.

ICP is all in who builds the injectors. You can get about 170cc or so at 2.4ms on a stock nozzle. With good tuning and a ficm tune to remove the limiters in the factory software you can hit you will get a stock nozzle and a modified injector to run well for a daily. Its been done before.

 

[thuglike]

FYI.....


http://powerstrokearmy.com/forums/showthread.php?t=47542

 

[KCTurbos]

Do you have a fuel pressure gauge? I hate to burst your bubble but, most trucks I see tune only cant maintain proper fuel pressure with the stock fuel system even with the blue spring and a new factory pump. Probably going to need more than just a regulated return, the stock pump just doesn't have the volume in most cases.

ICP is all in who builds the injectors. You can get about 170cc or so at 2.4ms on a stock nozzle. With good tuning and a ficm tune to remove the limiters in the factory software you can hit you will get a stock nozzle and a modified injector to run well for a daily. Its been done before.

Was this testing done on a flow bench? I wish I had a flow bench :lookaround: This interests me because I ran 175/stock for a while and it was a great combo. My tunes ran about 2.6-2.8ms The lowest I ever got my fuel pressure was mid 40s on a really hard 0-100 WOT but usually stayed in the 50s for normal daily driving. I managed to make 534hp with just exhaust, tune, turbo, and injectors. (no ficm tune, stock air fitler, no ported intake, etc). After a while I added 75% nozzles and I gained over 50hp. Fuel pressure started dropping into the 30s for really hard 0-100 WOT runs but was still 50s for my daily driving.


I had always understood that stock nozzles could get close to but not quite dump all of a 175cc injector (like you said about 170cc is average). But I gained 50hp. At a guess of 3.3cc/hp that would mean I gained around 15ccs of fuel. Maybe my 175/stock was only dumping around 165cc and my injectors might have really been cut to around 180cc... that would explain the 50hp (15cc) bump.

Once again I wish I had a flow bench

 

[KCTurbos]

If you hpop is in good shape then it should be fine for 190s and under.

IMO 175s have shown to run fine on stock fuel system. You will drop fuel pressure on really hard runs but I have never personally seen any ill affects from this or from anyone I know (im talking about 35+ psi). I know lots of guys that run 175s on stock fuel system who never saw any ill affects (other than 35psi fuel pressure on hard long WOT runs) Running slightly lower fuel pressure for a couple of runs every once in a while is not going to suddenly blow up your injectors. Although we know it is not optimal for sure. 190s usually prove to be too much for the stock system. A fuel system would definitely be a good idea with either injector combo (maybe even just adding a lift pump to your reg return)


I think 175/30 would be ok for a stage 2, but I think 190/75 will be too big for a stage 2. The stage 2 will have the edge when it comes to low end driveability with the tq converter locked but the stage 3 will make much more top end power and run cleaner at WOT. With the stage 2 I would imagine more around the 550 range and with the stage 3 more around the 600 range (give or take 30hp). Both are within your goals.

 

[MrOneEyedBoh]

Hmm yeah. I guess there has to be an end goal... Performance and money wise. I don't want to go further than a RR and possibly a 6.4 lift pump at the max. I just don't know the reliability on that as a lift pump