Injector sizing with dry nitrous
Thread Starter
Melting Slicks
Joined: Mar 2002
Posts: 2,874
Likes: 764
From: Sligo PA
Injector sizing with dry nitrous
Hey guys,
I posted this question over on LS1tech and didn't get a lot of info. Also I figured I would ask here instead of the C4 section because it's LS related.
I was looking for some advice on injector sizing for my LS swapped 84. I found a little info by doing a search but still some things I'm not sure of. So this is my setup
-Stock 6.0L LQ9 short block with new rings. Steel top ring gaped for juice.
-PRC ported 243 heads
-11:1 compression
-Summit 8707 cam (duration 226 int./238 exh. Lift 0.600 int./0 600 exh. 113 LSA)
-F.A.S.T. LSXR 102 intake drilled and plumed for direct port single stage dry N20
-Long tube headers 1 7/8 tubes and 3" collector
-3600 rpm FTI converter with 4L80e and 3.73's in the rear.
-58 PSI fuel pressure with Walboro 450 in tank pump
So I want to spray a progressive shot with a Holley Terminator X ECU. I'm trying to figure out what size injector to run. I can't get E85 in my area so I'm stuck with normal 93. I'm guessing the NA crank power would be around 475-500 hp. I want to be able to spray up to a 200 progressive shot.
All of the injector sizing calculators I have found only give data for naturally aspirated, supercharged or turbocharged. So I'm not sure what to go with for my setup. I was considering Siemens Deka 60's. They flow around 70 lbs at 58 psi of fuel pressure. Anyone have any incite?
I posted this question over on LS1tech and didn't get a lot of info. Also I figured I would ask here instead of the C4 section because it's LS related.
I was looking for some advice on injector sizing for my LS swapped 84. I found a little info by doing a search but still some things I'm not sure of. So this is my setup
-Stock 6.0L LQ9 short block with new rings. Steel top ring gaped for juice.
-PRC ported 243 heads
-11:1 compression
-Summit 8707 cam (duration 226 int./238 exh. Lift 0.600 int./0 600 exh. 113 LSA)
-F.A.S.T. LSXR 102 intake drilled and plumed for direct port single stage dry N20
-Long tube headers 1 7/8 tubes and 3" collector
-3600 rpm FTI converter with 4L80e and 3.73's in the rear.
-58 PSI fuel pressure with Walboro 450 in tank pump
So I want to spray a progressive shot with a Holley Terminator X ECU. I'm trying to figure out what size injector to run. I can't get E85 in my area so I'm stuck with normal 93. I'm guessing the NA crank power would be around 475-500 hp. I want to be able to spray up to a 200 progressive shot.
All of the injector sizing calculators I have found only give data for naturally aspirated, supercharged or turbocharged. So I'm not sure what to go with for my setup. I was considering Siemens Deka 60's. They flow around 70 lbs at 58 psi of fuel pressure. Anyone have any incite?
Advanced
Joined: Jul 2014
Posts: 72
Likes: 6
Well, I run 60lb/hr injectors in my race car, makes about 750hp on motor, have made about 1100hp on juice, 156 mph @ 3300lbs, so why you would need 60's for your combo is beyond me......... It won't hurt though, you can always grow into them! 
Thread Starter
Melting Slicks
Joined: Mar 2002
Posts: 2,874
Likes: 764
From: Sligo PA
https://www.rpmoutlet.com/fuel-injector-calculator.htm
If I had a total crank HP of 750 and an 80% duty cycle that would require a 61lb/hr injector at 58psi of fuel pressure according to that calculator anyway. That's also telling the calculator that it has a turbo being that "nitrous" isn't an option. So if I can muster 700 hp at the crank with nitrous I would have a little wiggle room. That and the Holley ECU that I'm using already has the calibration file for use with those specific injectors. So I guess they might be a little overkill. But at least I won't run out of injector. That and it's not like a smaller injector is any less money. Even a 50lb/hr costs about the same.
