Will my 42.5 lb/hr lucas injectors max out at 6500 rpm with my mods soon to come:

2.8 inch pulley
CAI
2.5 Catback
Short Tubed Header
Downpipe
High Flow Cat

 

your 42's will be fine.

I'm runing them with a rather extreme set up for such small injecters and i dont get above 94% duty cycle(when they go static) untill i'm above your clamed rpm limit of 6500.

i supose you might get close depending on your tune....but i dont think you'll be over.

 

Yeah, you'll be fine. Mine maxxed out with the 2.6" pulley but with a 2.8 I still had room.

 

Ok good, I heard in another thread yesterday that a 2.8 maxes 42.5 lb injectors out...I was like what!? Ok thanks. Yeah I'm going to be tuning it with my Maf Translator and monitering the a/f ratios with my aem wideband I just ordered today. Ordered about $900 in parts today lol. I'm broke, can't even put gas in my car lol. I have to walk to work today

 

My injectors are maxed out at 6292 rpm and reached a duty cycle of 109% at 6770 rpm.

 

How do you guys know what % the injectors are running at? What kind of gauge/tool do you use to read that information?

 

its not a gauge, they are most likely using a laptop with AutoTap software. Its an amazing software package to have, and tells you all you need to know about your car.

 

06black and I are using HP Tuners. I'll post a picture of my log in a few mins that shows you where they are going static.

 

You rich *****.....lol jk. I wish I had that kind of money.

 

HP tuners

 

you can use the Interceptor. Find a converter online for injector pulsewidth to flow %.

MaxBoost, i think you are seeing max because you have the GM injectors. They are designed to flow the given rate at our high fuel rail pressure. I believe the regular lucas injectors are designed to flow for a lower fuel rail pressure so they flow more at our hgh pressure. Please correct me if I am wrong.

 

Thanks. I never knew that. I will, at least when my gauge works, since it works like every 4 days.

 

yeah i used to have a site bookmarked that you could put in your lb/hr, puslewidth in ms, and it would give you your flow %. Of course, now I can't find it.

 

Found it! http://www.stealth316.com/2-calc-idc.htm pretty simple, i think it is right

 

Thanks a lot. I appreciate it

 

We aren't rich, we are bums using someone elses HP Tuners, lol

I never thought of that. It makes sense though.


Here is a screen shot of my log from last night.

 

42.5s are just fine for that set up. I think 42.5s are good all the way to a 2.6" pulley. The next step would be 60lb. Only needed with a 2.5" pulley.

 

Man I love that IAT2 readout and how steady your timing is. My car sucks ass Your LTFT looks a little off.

 

You Sir, are correct.

3.3" - 3" pulley -Stock Injectors
2.9"-2.6" pulley -42# Injectors
2.5" pulley -60# Injectors.

 

They are off because this run was made right after there were changes made to the tune and we didn't reset the LTFT table so it was dumping fuel and the STFTs were pulling it out. Enufpwr said it takes about an hours worth of driving to get it all worked out.

I disagree, while the car may run ok with the 42.5's ideally you don't want to be more than 80% duty cycle at any given rpm level. I think anything below 2.9 really should have the 60lb injectors especially if you plan on doing any more modding later.

 

Damn with my 42.'s and my 2.7 I'm only getting 51% duty cycle at 7411 rpm in 2nd gear.
haven't gotten enough room to do a run in third yet.

 

Yeah I agree with maxboost. you need to do a couple long pulls, you'll see how short of fuel you are. When I had my 2.6and 42s, at 6400 rpm i would see 130% injector duty if i remember right. I wouldn't run below a 2.8" w/o 60s now.

 

I'm def heading to the dyno this week.... I'm still running my stock exhaust so it shouldn't be too bad... damnit, here comes the 60's...

 

Don't hate the 60s...embrace them!!!!!!

 

pat and jason have give some good information sence I gave the first and totaly correct answer

had to take a stab at ya guys....

now to who ever started this thred....

with your set up you will be fine!...

i'm run my car HARD every day, and shes holdin up just fine!

also guys you cant forget that injecters go static below 1005 duty cycle...its around 94-96% so with jason at 100% there...and a few of my logs showing 115%-120%....but i've never had any engine problums!!!

I've broke everyhting else except that!!!

the only thing that you might want to be slighly werry of is staying at WOT for long periods of time. as long as you/me do that the smaller injecters will be just fine!

(for the time being)