which heads
 

i'm building a 347 stroker for a strret/strip car,

it's planned set up is like this

347 stroker
AFR 205 heads
edelbrock jr.vic intake
3.73 gears
comp cams 280HR

i bought the heads already after saking many questions on my set up, and now that there ordered i'm being told there too big, so just wanted some more opinions, alot of people are saying i should go with the 185's, and a dual plane intake like a weiad stealth intake, or edelbrock performer. i asked alot of questions before i ordered certian parts, and know people are saying not very streetable, so what do you think, it's not an everyday car it'll be my weekend toy, and 1/4 mile car, don't plan on a high milage car.

AFR 185 would be best for what you have planned. You won't like the 205's for the street.
auto10x
Bill

every one tells me i won't like them, but can some one tell me how they'll perform, explain why i won't like them? i'm not doubting any one, this is just my first engine build and i'm trying to get a full understanding of what i can. i'm not quit sure on the flow number thing yet, but it makes sence that if a head flows better all around then it would be just as good as the other+. can you just explain how they'll perform. just curious.

Because of the large ports you will get quite lazy throttle response at lower rpms. Also as the mixture velocity through the port will also be slow you may not get such good atomisation and fuel distribution. Im assuming that you are carburated and not fuel injected. The heads will be killer over 5000rpm though! As you have the heads I would give them a try, in a light car with 3.73 gears they may not be as bad as you might think. What do you expect to use as a redline? With the combination of heads cam and intake that you list the motor should rev to 7000+ easy.

A 347 is probably big enough to take advantage of the 205s if you build the top end (and bottom) strong enough to take some RPMs (5000+). Look at some of the builds in Fast Ford and Muscle Mustangs a few months back (late last year I think). They did a whole series on small block heads. Bottom line is the 205s are on the large side for a 347, but probably OK and if you ever wanted to go to a blower, you would have the perfect setup. Oh, and with the torque even with slow throttle response (which I'm not sure you will have), city driving will be enjoyable.

the current peices i have are a KB hyper pistons with 6cc valvle reliefs, forged i beam rods, JE rings, eagle crankshaft(4340), clevite 77 bearings, fel-pro gasket, AFR 205 heads, planning on using a weiand stealth series manifold so i can have more torque down low. and thinking about comp cams 280HR not sure on how to choose the cams though, so any suggestions would be great, and if you think this combo is good. i'm not sure about bring this upto 7k+. this is just my first engine build and would like to have a nice engine, the stall speed i was thinking in the 3000 range maybe a little higher. the title on the car says it's only 2300 pounds can't be right, it's a 79 mustang. not sure if the title was for a 4 cyl. or what so i don't have the weight, i can guess about 3000pnds or so. let me know you opinions, places for improvement, and if i'm looking at the right cam if i use the 205's

On cam selection, call one of the manufacturers and tell them what you have and what you plan on doing with the car. They will advise you as to the proper cam. More than likely a custom grind will make your selection of heads and parts work just right.

i was thinking of a custom grind does any one know if they are more expensive, and if so is it alot more, like i would consider 500 for the stcik to be expensive, i can do 300-350.

Most of the small block custom grinds I have seen are around $250. Try Keith Craft or Bennett.

280H cam is good cam. I'm running a 282HR.

205cc heads are really big for 347. I run 185s on a 408! Many say too small! I tend to agree! BUT!!!! 544 lb-ft. of torque probably wouldn't have happened (at least not as early in the torque curve) with 205cc heads.

W/ that cam and my 185 cc AFR heads, I can turn 1500 RPM on the highway if I have to (never want to) but the thing is a real babydoll at 2K-3K. Comes on good at 3K, at 4K starts screaming, and does so to 6500 when the valvetrain, intake, and heads all simultaneously give up....right where I want them to.

FWIW...
JP

In my experience you will have no problem feeding those heads. It dosen't sound like you much care about what happens below 2000 rpm. I would definately look into a custom grind roller, though. AFR is getting great flo no's with their given port sizes which equates into better port velocity over another head at the same size port. I don't think you'll need the (as much) split overlap that the 280HR has since the AFR's are going to be real good on the exhaust side, as well. The Performer RPM or Stealth will give you better throttle response and power below 2500, but you'll loose power where your heads (and appropriate cam) will really shine, at the upper range, say 6500-7500. If that's where you want to be, a single plane is better and the drivability difference will be slight, especially with a loose converter. I wouldn't be afraid to turn the RPM, given your parts, if you want the power. Lets face it...that's where small blocks make up for being small blocks...with RPM. RPM = more air, more air = more fuel, more air/fuel = more HP. You'll need a good carb, 750+, too. I'm saying all this assuming you'll run open headers when you're at the track. Mufflers and exhaust will slow things down a little, but there's some good exhaust products out there as well. Your package, with the right comopnents will make extremely good power and torque, and should be reliable enough for street use. Granted, it won't like 1500 rpm, but that's the trade off. The smaller heads won't give you near the power, everything being equal.
Good luck!

AFR focuses on mid lift flow numbers for their street/strip heads, which is what they call the 205. These heads are already flowing >.200cfm at .300" lift, and >300cfm at .550". Thats some pretty stout air flow for a 205 cc runner which equates to excellent port velocity. Check the other alum. heads on the market and none come close with even bigger ports. Check out www.airflowresearch.com. They could definately help you with a cam selection.

i appriciate all of the responses, i think i'll try the 205's out, i realy don't car too too much about how great it is on the street , as long as i can manage. so with that the 205's would be a better in the 1/4 mile then the 205's given i use a custom grind cam, and since i won't be giving up too much with a single plane i plan on using the jr. vic intake.

so jr. vic intake
AFR 205's
custom grind cam
3.73 gears
750 holley carb

and i'll be all set for some street use a little on the iffy sind but still managable? and thanks again all the responses are much appriciated.