Tuning for ram air

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fnaramore

fnaramore

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Hey guys! I'm putting a custom hood scoop on my car soon so iv been reading up on tuning the carb for it and here's what I understand at the moment. Should richen it out a bit (like 6%) for the denser air and to make sure that the top of the carb sits at least three inches below the scoop to prevent air from siphoning fuel as it passes over the carb.

Anyone got something to add, correct or have experience with this?
 
A lot depends on the type of hood scoop, some work great like the T/A challenger or A12 cars, and some don't do much like the 69 superbee/71 demon.
 
Well what it is coming together as is more of a hood scoop that would allow fresh air in rather than an actually tunnel ram. What I mean is at best the air filter would be just tall enough to be level with the hood, so theoretically no air that came in through the scoop would hit the air cleaner directly, at best skim the top. Question is, would this still be able to cause a pressure difference that would hurt the air fuel ratio? Iv be reading that for a true ram air setup it needs to be sealed or it screws up the calibration, but I'm not sure if that applies to this. I would imagine since no air is directly hitting carb/air cleaner, it would act like air entering the engine compartment normally at whatever speed say through the radiator/front grille
 
If the carb is sealed to the scoop you will get positive psi. The better the scoop the more psi.
 
No the engine will suck in cooler outside air mixed with underhood air. You have to jet it no matter what hood scoop or no hood scoop. That said most guys plop a carb on it and set the idle mixture screws and call it done.
 
Okay cool! Yeah I was figuring Id swap out the rods which should richen out the power band by 6% and the cruising band by 4%
 
Seal the air cleaner to prevent warm air from entering. Cut some openings in the bottom pan and pop rivet some rubber flaps to prevent positive pressure and allow any water to drain. You can also make a deflector for the front of the filter and run a tall filter above the hood.
I run an AFR gauge and have to fine tune idle mixture by opening an closing hood until it is correct. A real cold air system makes a big difference.
 
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