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-   -   Head Casting vs Flow Chart SBC (https://67-72chevytrucks.com/vboard/showthread.php?t=131055)

ChopTop 12-10-2004 03:19 PM

Head Casting vs Flow Chart SBC
 
In the past when I had more time to wander the net I used to come across some flow numbers for various sbc heads. Some charts varied in flow considerably for a particular casting. Does anyone have or know of, or even built thier own, Chart with info on several SBC head castings. Castings I'm interested in particular: 882's, 441X's, 441, 186, 993, 487X, 291, and small chamber 305 heads to exclude the Vortec.

Thanks for any help. :bowtie:

crazy longhorn 12-10-2004 04:17 PM

882,441, & 462 are listed here....http://www.chevyhiperformance.com/techarticles/41598/ the rest are pretty much aftermarket heads(good article tho). My guess (no info to back), other than driving those old cars.....the 186, 291, &462's should be pretty compairable. the 487's & 493's were not bad smog castings, very simular, & pretty close to the 441's (for power anyway). Not a lot of help, but if you are looking for the big flow #, the aftermarket is the best way to go. Good luck,crazyL :burnout:

Fred T 12-10-2004 04:19 PM

Car Craft has done a lot of head flow testing.

http://www.carcraft.com/techarticles...hev/index.html

383 Stroker 12-10-2004 04:28 PM

The site has head flow numbers for alot of heads. http://users.erols.com/srweiss/tablehdc.htm

ChopTop 12-10-2004 07:36 PM

Now that is some great info! Seems like the 882 head is a winner thus far, if not simply for it's abundance. Curious as to why they don't list the infamous 487X head with all the talk about larger runners. Still no info on 305 heads though?

crazy longhorn 12-10-2004 08:34 PM

Choptop, im not sure about all the flow #, but feel that there was more power in the old "fuelie" heads......maybe partly due to higher comp ratio? i ran a set of 492"s (Z28/LT1 castings) , on a .040 over 327.....with a very mild cam, that little booger ran like stink! the cam was 216 dur @ .050, & mid .450 on lift.....with a 3.73 gear set, & a saginaw 4spd, with a 3.50 1st gear.....that 1/2 ton truck really didnt care if she was running empty & smokin hides, or pullin 10-12,000 lbs ;) crazyL :burnout:

BADGMC 12-10-2004 10:05 PM

Big thing is that the older heads were a lot more heavy duty than the newer smog heads and many had smaller chambers for more compression. There is a lot more meat for porting and such to get more flow and compression which equals more power out of them. As for the 305 heads the two castings to look for are the 416 and 601 castings. These were the ones on the high output 305's in the 80's. But remember they are thinner castings so you can't do too much with them. I had 601's on my 305 in my 85 and with an intake, cam, and headers with good exhaust it ran mid 15's and surprised more than a few 350 powered trucks.

ChopTop 12-11-2004 08:12 PM

I'd hate for this thread to just dye off! I mean where are all the humble servants that obey my every command or wish?
Seriously though, don't see anymore responses about flow, so.. I though I would request someone elses time and money and have them make a desktop DYNO comparison between some good 305 heads and some open chamber heads like 487 or dare I say 882. Now I know the 305 head won't flow as good, but there is a measurable difference in Compression to consider. Any takers? Basic 355 sbc 450 lift cam small headers with flattops - Quadrajet. Thanks

cableguy0 12-11-2004 08:15 PM

the thing is you can have all the compression you want it wont make power unless the heads will flow enough fuel and air and the 305 heads will not. not to mention they are thin to start with any porting hopes are out the window


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