AFR heads: Anyone else interested in buying?
 

I am looking for more power from my HP 500's (carb). I would like to place an order through a local engine builder with AFR, the larger the order the better the price. If someone else is interested in the same combination I will share tuning information and dyno results. P.M. me if interested. Jeff

Re: AFR heads: Anyone else interested in buying?
 

I have an efi 500, and would be interested in a set of the AFR heads, but only if they increased power at least 50hp. Anything less and I might as well just have the stock heads ported.

Re: AFR heads: Anyone else interested in buying?
 

Chase910
I am looking for a solid 600 HP at 5400-5500, that is why I am willing to pay extra for better heads.

Re: AFR heads: Anyone else interested in buying?
 

600 might be asking a little much from a stock 500hp with just afr head. afr is the top of the line but even at 80-90hp increase over the stock 465hp(or whatever the 500hp carb motor is) still does not get you close to 600. i dynoed a 548 with a beefy cam and afr 335 cnc ported heads and it was 619hp on dyno headers.

Re: AFR heads: Anyone else interested in buying?
 

500 HP at the flywheel, 470 HP at the prop. You will need a cam change and some carb and intake work to get 600 HP but I am confident it will happen. Jeff

Re: AFR heads: Anyone else interested in buying?
 

Research the info with the search tab, I believe that there are several combos with AFR heads making 600+ HP with good flowing heads and cam changes, the extra HP from a 540 is only worth 38 cubic inces x 1.1 or 1.2 HP/cubic inch, so it is very feasible. Let me know as well for I am intersted in a set at a good price. I have been watching them on EBAY for a while now.

Re: AFR heads: Anyone else interested in buying?
 

jeff i don't know what 500hp you have that makes 470, merc always rated them at 465 at the prop but what is 5hp. all the carb work you do will not turn into any hp. it might run perfect or lean if you want hp but carb work will not make and real hp. as far as cam's go. sure you can find the right cam to make that power, but not to work in a boat right. last i have used and dynoed several motors over the last few years and afr's are the best(although i use pro ones) but i dont care what they tell you the dyno does not lie. best we ever got on a 548 with a large cam( really to large for a boat) 335 cc cnd ported heads (25cc larger than you want to go. nickerson carb, msd ignition locked at 35 deg. was 619hp. and that was pushing it. we only saw those numbers after a bunch of messing around with jets and timing. so the motor had 25 cc larger heads, a larger cam, a perfect pro built carb, 500hp dart intake 9.5 comp and 46 more cubes and it only made 619hp. i am not trying to give you crap i just want you to not be disappointed when you dont get the 600hp you are looking for. you can keep your motor bone stock, send the carb to nickerson, buy a used m1 procharger for like 2k and have 650hp no issue.

Re: AFR heads: Anyone else interested in buying?
 

this is the last thing i am going to say on this. i know what people claim and what a dyno tell you always seem to be diff. is 550hp (real hp) possible for sure. is 600hp. maybe. like you said 1.2 hp per ci even at a 548 vs a 502 there is a 55.2 hp diff there, and that 619hp was on dyno headers so take another 10hp off that( at least) for gill headers. now we are looking at 619(made with our afr setup) subtract 55.2hp(cube diff) 10hp(dyno headers) that puts you at 553.80hp. strange, just about what i said is a realistic number from that setup.

Re: AFR heads: Anyone else interested in buying?
 

Have yall looked at the Dart Pro 1 heads. Compared them to the AFR heads???

Re: AFR heads: Anyone else interested in buying?
 

Strip Poker, I'm running the Dart Pro 1's 325cc's on a pair of stroked 454's (496's) and have been very happy with them so far. Very similar setup to these:

http://cgi.ebay.com/ebaymotors/ws/eB...spagename=WDVW

Bryan

Re: AFR heads: Anyone else interested in buying?
 

Rob,i just looked at the flow test #'s,a dart pro 1 w/325 cc intake port as cast had a flow of 325cfm intake/223 exhaust at .600 lift,a set of out of the box as cast afr 305cc intake port heads have a flow of 363 intake/276 exhaust at .600,ABSOLUTELY NO COMPARISON.My world vr's have a flow of 313/207 at .600 !!!I guess next time i buy heads i will do more research!!!

Re: AFR heads: Anyone else interested in buying?
 

Thats a lot of difference :eek: .

What about the flow at low lift #'s where the torque comes in to play?I wonder what the price difference is ?

Has any body compared the Eldebrock alum. heads???

Re: AFR heads: Anyone else interested in buying?
 

Thats what TMP uses on most of there motors.must be a reason???

Re: AFR heads: Anyone else interested in buying?
 

The Dart CNC Pro 1's have an advertised flow slightly higher than the AFR CNC heads. The AFR's exhaust appear better, but they insist on running a pipe for some reason which gives them another 5 - 7 % on the bench. I chose 355 Dart Pro 1's for my NA 598 and it has very strong HP!! I agree that 600 HP for a 500 HP base is attainable, but it will be at high RPM's (like 6000) with good headers and probably a 1050 carb. This combo may not be real tame idling around the docks, but it can be done.

Re: AFR heads: Anyone else interested in buying?
 

I'm not a head guy but are you talking iron or aluminum heads.My 540 made 625hp at 5700 with stock gm heads and I was told with the AFR,s it would have made about 700.Going aluminum you can bump the compression a point.I don't know what a point in compression is worth in HP.

Re: AFR heads: Anyone else interested in buying?
 

Rob(strip poker)here is a more complete list of flow #'s,all of these #'s are as cast,i couldn't find ant cnc flow #'s on the dart pro 1's. Out of the box on a motor with .600 lift or less the afr's with a 305 cc intake port kick the dart pro1 a--,even if you compare the dart pro-1's w 345/cc intake port !!
AFR 305 as cast pro-1 325 pro-1 345 AFR-345
.200 163/135 141/93 141/106 141/135
.300 241/192 200/135 199/138 212/169
.400 300/237 251/170 254/173 279/219
.500 344/268 293/200 292/204 333/249
.600 367/284 325/223 323/224 372/272
.700 368/298 -------- 350/237 401/285
What these #'s tell you more than anything is a out of the box afr 305 is a exceptional casting,a out of the box afr 345 will only hurt your power unless your running a 700+ lift cam and the dart pro-1's MUST be ported to even keep up(i think they must be designed with the intention of only being run AFTER full porting),SMITTY

Re: AFR heads: Anyone else interested in buying?
 

I was just looking on AFR's website and it gives the flow numbers. Interesting is that the best to me is the 315CNC head which out flows all their other heads-305as cast, 325as cast, 335CNC, and 345as cast. The 335cnc beats it at .600" 385 to 380 and the 345 only beats it at .700" 401 to 386.

When I buy a set of heads it will be the 315CNC.
They flow .2"=169, .3"=249, .4"=312, .5"=353, .6"=380, .7"=386

Re: AFR heads: Anyone else interested in buying?
 

Marty,i know what you mean! These afr 305's as cast put my merlin's to shame,there would be such a big gain for me over my merlin vr's (average of 25% between in/ex) AND a exhaust balance at almost 80% vs. 65% that i'd almost skip the cnc job! The 325/345's offer almost nothing (except worse low lift flow!) I know what i'm getting next time!,Smitty

Re: AFR heads: Anyone else interested in buying?
 

gen4 509", pocket ported gm rect. heads, merlin marine intake port matched, 9.8-1 comp forged je and polydyned, 92 octane, ultradyne roller cam, holley 850 with proform main body, 580hp/580ft.ibs at 5300. over 500ft.lbs from 2900 rpm up. Would have liked better heads but this is best I could get on a budget.

Re: AFR heads: Anyone else interested in buying?
 

Thanks for the feed back everyone, some good research going on here. I am still undecided on the 305 with cnc cambers or the 315 with complete cnc. I don't know if the 502 will benefit from the 315, What do you guys think? I can't wait to get these on the dyno and back in the boat to see what really happens. If any one else is serious please p.m. me and we can get some prices and get this going.

Re: AFR heads: Anyone else interested in buying?
 

wags,I'm seriously thinking about the same two pkgs you are,hard coated with a set of iconel valves minus springs/retainers. The only thing is i willl probably need to buy them on my visa which won't work as a pkg deal,are they going to go much less than racer net if you buy 2 sets?pm me and let me know,Smitty

Re: AFR heads: Anyone else interested in buying?
 

Are you going to use the Comp 'Beehive' springs and titanium retainers?

Re: AFR heads: Anyone else interested in buying?
 

wags pm me a price on what 3 pairs of the afr 347s cnc'd would run me please. complete for blower motors. Iconel valves, hard coated as well please.

Re: AFR heads: Anyone else interested in buying?
 

I hope you would be able to do better than jobber at least 5-10%off. If any body pays racer net or above is getting screwed!!

Buying 2 or 3 sets at a time should qualify as engine builder ,sometimes engine builder is the same as warehouse distributer price structure.I am shure if you have a group buying we could get Too old to get set up as a WD.Its not hard.


Let me know if you have to pay above jobber

Re: AFR heads: Anyone else interested in buying?
 

I have afr 335's. I went & had my heads flowed when I got them from afr & they flowed better numbers then what the web site says. My engine builder said he has flowed a number of afr's & has yet to see any that were less then the web site. I do not have the numbers but I have posted them on OSO before.

A number of people have told me that the AFR's have more meat to them then the Darts do & have less problems with blowing head gaskets.

Re: AFR heads: Anyone else interested in buying?
 

I think unless I was building an insane 502", my choice would definitly be the AFR 265 ovals, cnc ported to 290cc on the intake....the as cast 265's compare VERY favorably with the as cast 305's. I think for a 502 turning 5500r's that this is the ultimate head! At least with any lobe design that I would use on a marine engine. I would also seriously consider them for a 540ci...they might be a little harder on the drive though! LOL

Re: AFR heads: Anyone else interested in buying?
 

What are the flow numbers for the 290CNC? They are not on their website.

Re: AFR heads: Anyone else interested in buying?
 

Here are some flow numbers off my flow bench @ 28"

.................AFR CNC............................................Dar t Pro One Ported ex


Intake........ex............Re ported chamber
.2 160......133..............172.........136......... .........................133
.3 228......184..............250.........193......... .........................173
.4 297......226..............312.........239......... .........................240
.5 349......249..............357.........261......... .........................277
.6 384......259..............388.........263......... .........................296
.65 393.....260..............397.........263.......... ........................299
.7 398......260..............400.........263......... .........................306

The Intakes work well out of the box, with extra porting even better. The exhaust out of the box are turds at best. The tests were conducted without a cheater pipe on the exhaust port. It's more clear, after looking at the second set of exhaust numbers that the port is peaked at 1/2 inch lift, indicating a restriction in the port. Extra porting is needed on the CNC ported AFR's to duplicate the dart numbers, or to make the port "right".

Re: AFR heads: Anyone else interested in buying?
 

jim,are these flow #'s for afr's or dart pro 1's?

Re: AFR heads: Anyone else interested in buying?
 

Hi Jim: Congrats on your win at LOTO! I meant to get together with you but it was too busy. Question, on a blower engine (centrifugal) would it make sense to leave the intake alone, concentrate on the exhaust and still use a dual pattern cam? You know what I'm thinking; good low end torque, but lots of exhaust flow for when you are under boost.

Re: AFR heads: Anyone else interested in buying?
 

Thanks Tom! Sorry I couldn't spend more time on the dock, like you, it was busy for me too (thrashing to find a prop). Your chiller set up looks great.

As for the intake ports, yes if it flows a decent amount of air. Most heads need a bowl port and your good to go.
On Check30's 572 twin turbo motor the ports are small enough in volume that it would scare most. It makes a buttload of torque and the motor will still rpm. The intake holes measure 2.1 tall by 1.75 wide and flow in the 385 range. Im sure the efi helps too. Bill will be at Hardy this weekend. He promised me a ride and I'm gonna make sure he sticks to it.

Re: AFR heads: Anyone else interested in buying?
 

Belt driven centrifugals and free floating turbos have very similar boost and HP curves. They come on big time at mid to top range, so you don't need to worry as much about intake flow numbers, but you do need to keep the low end torque.

My experience so far has shown that good heads and mild hydraulic roller cams are the best in the real world. They get the RPM up quickly, then the blower takes over. The blower keeps the torque curve going a lot longer than the cam would suggest. You know this when you see the dyno sheet and the torque peak is only 500 RPM lower than the HP peak.

All you guys building 502/540 keep the compression lower than 9:1. You should see 600 HP and if you use good head gaskets and exhaust valves, you're just a blower away from 1000 HP.

Re: AFR heads: Anyone else interested in buying?
 

jim,your flow #'s on the afr's,were they with a 4.250 cyl adapter or a 4.500? I am on the hunt for the ideal head for my blown 540 this winter,i'm currently running merlin vr's have you flowed any of these?The info iv'e found shows exhaust flow around 200 cfm,i assume it must be holding me back more than anything else. Do you do head work as a business,i don't like to wait 9 months for lapouttre to port heads for me,Smitty

Re: AFR heads: Anyone else interested in buying?
 

Jim have you ever flowed the the Canfield 310cc head?

Re: AFR heads: Anyone else interested in buying?
 

I thought AFR bought Canfield?

Re: AFR heads: Anyone else interested in buying?
 

JimV
Thanks for all of your information. If you were buying afr heads for a 502 with a max rpm of 5500 what would be your choice? Jeff

Re: AFR heads: Anyone else interested in buying?
 

Wags,
E-mail me at [email protected] I would like to discuss an option.

Chris

Re: AFR heads: Anyone else interested in buying?
 

Articfriends All flow numbers are with a 4.600 flow plate. The Dart heads are superior to the VR Merlins by far. 400 cfm @ .700 is doable with the Darts, no way with the Merlins. Also, to get the air flow numbers out of the Merlins you will be into the water jacket. Yes I do heads for a living. BTW I used to work with Rick at Dart years ago

Re: AFR heads: Anyone else interested in buying?
 

Wags

That's a tough question to answer without more info about the motor. What compression, exhaust, peak airflow numbers. Generally I will run a cam lift that is at the peak airflow. The duration will vary. Hull design and boat weight is a factor

Re: AFR heads: Anyone else interested in buying?
 

JimV worked Canfield Heads, bowl port intake, full port exhaust

.2 150 140
.3 230 181
.4 297 220
.5 342 253
.6 360 275
.65 - 283