I'll add some personal experience to it.
I had 90hp Dynomite Diesel injectors in my truck with the 68mm Cheetah and my EGTs wouldn't go over 1400* at WOT 4WD runs to 120mph. My PW was at 1960, timing didn't go above 26* and I was running 12.36 at 108. After the headers and up-pipes I installed a drive pressure gauge and started playing with turbo tuning to get rid of drive pressure. I was to where it wouldn't get over 1250* no matter what I did and it was feeling a good bit faster than my 12.3 runs.
I do tuning for a guy in AZ that has the same setup as I do except for stock injectors. I set him up with my tune but with fueling and timing for stock injectors (same style of tuning just higher numbers) he ran 12.66 and his EGTs get much higher than mine did. His altitude accounts for some of it and I forget his trap speed but know it was a few mph slower than mine.
On my built motor I will be using 100% over injectors and plan to keep my PW under 2200 and my timing down while getting enough fuel for a 3.0 charger. IMO big injectors have proven to run the same or more power with lower EGTs. Jneals truck dynoed 730hp and ran 11.55 with 60% overs, a 71.5mm cheetah and dual fuelers - on fuel with a stock LBZ motor.
On a side note I hate HP ratings on injectors - we don't have a Cummins that is limited by a smarty stacked with whatever else. I can take a stock truck and add 120 hp to it with tuning or take a truck with "120hp" injectors and take out fueling to make it run just like stock. IMO actually flow ratings and % over ratings (based on flow rates, not hole sizes) are much more realistic for EFI Live users and will make tuning for bigger injectors much easier.
I had 90hp Dynomite Diesel injectors in my truck with the 68mm Cheetah and my EGTs wouldn't go over 1400* at WOT 4WD runs to 120mph. My PW was at 1960, timing didn't go above 26* and I was running 12.36 at 108. After the headers and up-pipes I installed a drive pressure gauge and started playing with turbo tuning to get rid of drive pressure. I was to where it wouldn't get over 1250* no matter what I did and it was feeling a good bit faster than my 12.3 runs.
I do tuning for a guy in AZ that has the same setup as I do except for stock injectors. I set him up with my tune but with fueling and timing for stock injectors (same style of tuning just higher numbers) he ran 12.66 and his EGTs get much higher than mine did. His altitude accounts for some of it and I forget his trap speed but know it was a few mph slower than mine.
On my built motor I will be using 100% over injectors and plan to keep my PW under 2200 and my timing down while getting enough fuel for a 3.0 charger. IMO big injectors have proven to run the same or more power with lower EGTs. Jneals truck dynoed 730hp and ran 11.55 with 60% overs, a 71.5mm cheetah and dual fuelers - on fuel with a stock LBZ motor.
On a side note I hate HP ratings on injectors - we don't have a Cummins that is limited by a smarty stacked with whatever else. I can take a stock truck and add 120 hp to it with tuning or take a truck with "120hp" injectors and take out fueling to make it run just like stock. IMO actually flow ratings and % over ratings (based on flow rates, not hole sizes) are much more realistic for EFI Live users and will make tuning for bigger injectors much easier.
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