CFM, stands for cubic feet per minute. That's determined by the size of the bore in the carb throats. Your engine will pull only so much air at a given RPM, that air p***ing thru the venturi of the carb will pull fuel out if the bowl thru the jets. Too big a carb and the air flow thru the venturi is too low. Too small a carb hurts on the top end of higher Rpms because its a restriction. A smaller carb will work fine until the max CFM becomes inadequate for the engines demands at high rpm..
People get rid of those predators for a reason, if you are on a budget then go with the Q-jet or at least start with a 750 Holley. "I sure get tired of seeing letters from ****-retentive,self-styled engineers who bring up the tired argument that an engine is not a motor. A motor is an electric blah blah blah...Buzz off, Edison ! While an electric motor will never be called an engine, it's been generally accepted for a century that an engine can also be called a motor. Ever hear of motor oil, motorcycles, motorhomes, or the Department of Motor Vehicles ???? These are the same twits who think the new millennium began in 2001, not 2000. Shut up ! Jeff K." one of my favorite quotes ha ha ha
Depends on the ring gear size. I have a Nova 10 bolt 8 1/2" gear in my cpe with a 425hp/454 crate motor. I have 85,000 mi on it and they have not been easy miles either. It has been on the strip more than once and anyone who knows me will tell you I don't baby it. I think the Lunati cam your looking at is a little more than you really want. I think the Lunati cam you're thinking of is more than you want. A Holley 750 vacuum advance would work fine for you. That's what I'm running on the 454 in my cpe and also on the 489" stroker I have in my 85 GMC crew cab dually
I would go for a 383 if you are looking for a punchy street engine. Yes a little more work and money but a proven engine that will light up the tires but not drink the gas like a big block. Just make sure you dont put a powerglide behind it to kill your mileage.
Not to keep harping on air fuel combos but the motor is tbi would i be able to put even bigger injectors aand get the same cfm as an 850 holley or should i go ahead and convert to carburation
Injectors = fuel Jets = fuel CFM = cubic feet per minute OF AIR. same as before, determined by the bore size. In the case of the TBI, the bore of the throttle body.
And the ratio of air to fuel needs to be right. If you have more air, you need more fuel. With a carb, it will "adjust itself" for the most part, it lets more fuel thru when more air goes thru. You can run the same jetting (in the same size carb) on a small engine or a large engine. But fuel injection needs to be recalibrated or have the injectors made bigger if you have more airflow.
^^^^yes, the EFI injectors need to be told what to do based on inputs. I agree. But this vvvvv is in response to 58chevrolets comment below. Bigger Injectors will not create more CFM , just likethequestion a few posts back about changing jetsin a smaller carb to create a carb capable of more CFM. (post 25)
I'd go ahead and convert it to the carb, it has the added benefit of not needing the computer for the swap.
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