The 409 aluminum heads are said to be for 1500 to 6500 rpm while the performer basic is for idle to 5500. Anybody have experience with a 348 with Edelbrock aluminum heads between idle and 1500 rpm?
The difference has to do with the cam.The 1500-6500 is for a hyd.roller cam,the other,flat tappet.Unless stroked,the eddie heads are a bit much for a stock stroke 348.You'd be better off with 817's,1147's or 333's,especially on the street.
I want to understand if the thousands will be worth it for a cruise car that rarely revs more than 3000 and may spend s lot of time at 11 to 1500. I assume I must also stroke it but possibly stroking alone will increase torque on an already torque motor similarly without the big extra cost.
The big ports and valves will make that small of an engine feel"soggy"below 3500.You could use the aftermarket stuff p[Edelbrock or Bob Walla
] on a stock stroke 348 if it was built with very high[11 1/2 and up]and lotts of cam and rpm,but that is the opposite of what you propose.A more budget and sensible approach would be to stroke it with a 409 crank,use aftermarket 6.385 rods and KB Icon pistons.This will put you in the 380 cubic inch range,and with 817[340 horse 409] heads,it'll do what you want with either a 218-224 duration @050 or a 224-230 cam.