yossarian19
NAXJA Forum User
- Location
- Grass Valley, CA
Ok. I've been reading through Dino's site every couple months as I learn more about engines & tech and it makes more sense every time. Now I've got a question:
In 96 they bumped the fuel pressure from 39 to 49 PSI and the lbs / hour from 21 to 23.2.
Add enough airflow mods (cold air, TB, 99 intake, headers & exhaust, etc) and you start to run lean. Relocating the intake air temp. sensor to a colder section fools the engine into feeding more gas but eventually this isn't enough. Dino and many others found the need for heavier injectors to keep a high performance 4.0 running a proper air/ fuel mixture. Ford 24 lb injectors fit the bill for some strokers but at 4.0 displacement, they are overkill - now you run rich, drop the IAT trick and go with a MAP adjuster to change the duty cycle on the injectors, keeping air / fuel proper.
This is all on a 95 or older engine.
If you are running the 49 PSI / 23.2 lb injector setup with OBDII computer, could you manage the full package of intake / exhaust modifications (naturally aspirated) and bump to 9.5 compression, stick a new cam in there and expect the factory fuel / spark control to keep it running properly? Expected power output with 99 intake, 2.5" hi flow exhaust, bored TB and free flow intake?
In 96 they bumped the fuel pressure from 39 to 49 PSI and the lbs / hour from 21 to 23.2.
Add enough airflow mods (cold air, TB, 99 intake, headers & exhaust, etc) and you start to run lean. Relocating the intake air temp. sensor to a colder section fools the engine into feeding more gas but eventually this isn't enough. Dino and many others found the need for heavier injectors to keep a high performance 4.0 running a proper air/ fuel mixture. Ford 24 lb injectors fit the bill for some strokers but at 4.0 displacement, they are overkill - now you run rich, drop the IAT trick and go with a MAP adjuster to change the duty cycle on the injectors, keeping air / fuel proper.
This is all on a 95 or older engine.
If you are running the 49 PSI / 23.2 lb injector setup with OBDII computer, could you manage the full package of intake / exhaust modifications (naturally aspirated) and bump to 9.5 compression, stick a new cam in there and expect the factory fuel / spark control to keep it running properly? Expected power output with 99 intake, 2.5" hi flow exhaust, bored TB and free flow intake?
