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AFR BBC Oval Port Heads

91K views 177 replies 56 participants last post by  Stokerboats 
#1 ·
Anyone have an update and some accurate spec's on these head's?
 
#2 ·
You would think with all interest surrounding these heads AFR would have made it point years ago to get them done.
 
#5 ·
Guys,

There were reasons this product launch took so long (some of which simply related to priorities of other new product) but the bottom line is the product we will be offering you is even better than it was originally slated to be. It will include a FULL CNC intake port for more flow and better consistency and a partial CNC exhaust port in the VJ to bowl transition. Chambers are as cast and of course we offer the CNC chamber upgrade which is really a home run on this product and I highly recommend it if you have a few more hundred to spend (worth 30+ HP).

The small 265 version will be our first product launch.....it flows over 340 CFM with excellent low and mid-lift numbers (insane for that small a finished runner size) and we should be taking orders soon on that product.....less than 30 days. I will notify you guys personally when we open our doors to deposits.

Sorry for the long delay....it will be worth the wait!

-Tony

PS....290 cc version about 2-3 months out....full CNC on intake, chambers, and exhaust. More info on that as it draws closer.
 
#6 ·
#10 ·
Tony the heads sound great,the 265 version should make a 396 a beast. Just make sure they come STANDARD with ARP studs.:beers:
 
#12 ·
RR BB-O 2.250 Intake 159 223 270 314 334 336 340
-------1.880 Exhaust 116 145 172 196 217 230 236
RR BB-O
(CNC Combustion Chambers) 2.250 Intake 160 224 280 321 340 342 344
--------------------------1.880 Exhaust 113 147 179 203 222 231 236

flow #'s are @ .200-.300-.400-.500-.600-.650-.700

I'm sure they dont flow with AFR's excellent exhaust ports, but a little more duration will help that. I'm using the cnc comb chambers on mine.
 
#13 · (Edited)
AFR's will likely be worth 30-40 more HP with no other changes....perhaps more in a very aggressive package with more RPM potential and a mechanical roller.

And Bob, I understand you not waiting....and for you guys who have accused me of crying wolf to some extent I dont blame you either but don't shoot the designer/messenger!!....LOL

Also....when have I ever brought you updates with more specifics on the actual product....never once as far as I know. Here is the reason I make the claim I do regarding power....smaller port (with a smaller valve) flowing like so with our CNC chamber upgrade....

Int.

.200....174
.300....246
.400....298
.500....330
.550....338
.600....346
.650....347

Huge area under the curve and an early very usable peak number.

Exh (+.350 raise....NO BIG DEAL)

.200....160
.300....197
.400....231
.500....253
.600....267
.700....278

This was ran like a production part untouched by myself or anyone else. These numbers are right off the CNC machine. We will likely advertise a little less because we always want to meet our advertised data but a handful of heads I have tested recently have met these numbers. Without the CNC chamber the head actually goes mid 350's but that just looks sexy in the advertising....the CNC chamber has much more area under the curve and will make more power.

Also, these numbers are not from a large bore fixture....we used a 4.310 bore for the testing.

Lastly, the AFR piece is equipped with a 2.19 valve.....more room on smaller bore engine combinations. The larger full CNC 290 version with have a 2.250 valve in it.

I promise you guys your going to start seeing oval port dyno results you are not accustom to seeing with both of these products. They will fill the cylinders like nobody's business and having an exhaust port this efficient is a key part of the recipe. Once you cant exhale the complete spent gases your next induction stroke is compromised and your power/torque starts falling away quickly...

Don't be quick to discount you need a really good exhaust to put up the big numbers....it really is a very important piece of the puzzle. It also allows you to run alot less exhaust duration for improved torque in the lower and middle part of the curve.

-Tony
 
#15 ·
The numbers will in fact be quoted on a 4.310 bore and I expect 370 CFM from that product but right now that number is purely what I reasonably think I can achieve from it based on my work with the smaller 265 piece.

In short its purely a goal at this point but one I feel I can achieve. Keep in mind we are discussing a port that will have a finished volume of under 300 cc's and hopefully flow close to the number I just quoted....pretty serious piece that will pack some serious airspeed and HP potential for you sub 500 CID guys....

-Tony
 
#16 ·
Tony, will these "oval" port head's be the 049 type port or something different like the 502 version of an oval port and will the 295cc port use the same dimension on the raised exhaust? i.e. .350? Thank's, Dan
 
#17 ·
Those are some huge low lift numbers. What intake valve do you use, and is it backcut? How do these do above ..700? Do they stay stable or fall off? What about left vs. right port?

I have a friend who got 360+ out of the TFS ovals with the 2.25, as cast with just a hand bowl blend, but not sure where his low lift was.

That's pretty impressive to say the least on the AFR's.:thumbsup:
 
#20 ·
Thanks...

Regarding the TFS, how large was the finished port volume? What test bore, bench type etc. and of course the curve is far more important than the peak flow. Our as cast chambers flow a higher peak (mid 350's) but the CNC chamber version would destroy it on the dyno.

The 265 will back up a little @ .700 (a useless number to consider for this product)....and some of that is inherent in the design which allows it to flow so strong at the liftpoints which matter the most (from the crack of the valve to .600 ish lift). Its always a compromise....also, when you place a manifold in front of it you wont see that port back up at the .700 mark anyway (real world scenario) so you could still run that much lift if you so desired. The short port has similar flow number till .400 lift which is outstanding and then falls back about 20 CFM by .650 or so. Thats actually also an accomplishment if you have had the luxury of seeing alot of whats out there fall short by alot more than that.

And yes....our intake valve is back cut specifically per my spec that I experimented quite a bit with during the development of this product.


Tony, will these "oval" port head's be the 049 type port or something different like the 502 version of an oval port and will the 295cc port use the same dimension on the raised exhaust? i.e. .350? Thank's, Dan
Good question actually.....we decided to design them just like the later GM stuff in the "roval" configuration. The main reason was I felt that shaped entrance would ultimately be more conducive to a better approach/design heading into the critical short side of the intake port.


It appears to me the 305 cc w/CNC chamber would still be the better head for a 700 HP 454 based engine.
I agree....but is our 265 really the right head for 454 based platform you have your sites set on legitamately trying to achieve 700 HP (an obviously aggressive application)....not at all.

However I feel the 290 will hand the 305 its walking papers albeit at a slightly higher cost of admission (Full CNC versus as cast with CNC chamber). For fun I plan on testing the 265 against the much larger 305 (think it will be a really cool comparo) and my guess is we trade 20 ft/lbs of torque for 20 peak HP but at this point its all speculation.

Also, more importantly the part throttle response and SOTP on the street would be night and day better with the 265 (versus the 305)....but unfortunately its difficult to impossible to measure that on an engine dyno which purely focuses on WOT data points. You can always get away with a larger head on an engine dyno test but in the real world unless you have the right combination, a larger head isn't always the best choice (although it can be if you have a light car and a 5500 stall!).


They sound impressive, now lets see em.
OK Ratt....we get your frustration over the delay. Time to lift just a little, cut us some slack, and be thankful/hopeful it is as good a product as I describe.

Sitting from my vantage point however Im confident they will be and I'm looking forward to seeing what they produce on the dyno shortly.

:beers:

-Tony
 
#19 ·
They sound impressive, now lets see em.
 
#24 ·
Wow....all this info makes it seem like my 305's that were on my 6000 rpm 454 seem like a bad choice :(
 
#26 ·
"Bad choice" is a bit aggressive....LOL

The 305 is an excellent head with a very modest cross section to promote good low speed TQ, and it flows enough air to also make big power if utilized/tapped into properly (solid roller, single plane, and RPM's).

That said, if you spend alot more time on the street than staring down a X-mas tree at the track, and you run a dual plane intake and a hyd. roller combo that limits RPM to 6K, I would say yes, the 265 is a better choice because your really not fully exploiting the airflow and RPM potential the larger 305's offer.

Nothing new here.....combination is still and always will be KING and a 454 at 6K is probably better served with our new 265 all else being equal. The only thing you would effectively be giving up is a little more low RPM and part throttle torque....at 6K or so the 305 might even make a few more ponies but my guess is the two curves are extremely close there.

I will have alot more real world data and less speculation over the next few weeks.

-Tony
 
#32 · (Edited)
Guys....

Please get that this is an extremely capable street head.....Its a street head first and foremost but one that would still be respectable at the track in the right configuration.

Its not aimed or marketed to be the ultimate strip head because when I think strip I think more cam, more compression, mechanical roller, and more RPM. Now we might consider a 315 or even larger in a max effort build.

In a 454 that you wanted to terrorize both (street and strip) the 290 cc oval would do some serious damage, but would need a mechanical roller to stay out of valve float and stretch her legs.

Dont get me wrong....Im going to test this on pump gas 91 octane and put the screws to it with a mechanical roller and a single plane intake and I hope to see 650 - 675 HP with a 10 to 1 thirty over 454.....maybe it will make that and maybe it wont but those are my hopes. What I'm more interested in however is what the rest of the curve looks like and that's what holds particular interest to me.

The reality is this would be a perfect head in your tow rig....a 3500 series 454 dually with a small cam and a dual plane intake and headers. It would rock right off idle and make big torque everywhere.....however change up the combo a bit and it will also deliver in your street/strip Chevelle. It has a wide array of applications due to the fact its a small runner that moves alot of air with a very impressive curve from the crack of the valve to .650 lift....covers the entire gambit of any cam you are likely to run in a true 265 cc ideal combination. Our 315 is very similar but made for slightly larger combinations ideally.....you could put one on a 454 and make great power and install the same head on a 555 and also have great success....the key to both is they are very efficient and move a ton of air per their given volume and cross section....thats what makes them extremely flexible and able to cater to many different combos.

-Tony
 
#33 ·
Guy....

Please get that this is an extremely capable street head.....Its a street head first and foremost but one that would still be respectable at the track in the right configuration.

Its not aimed or marketed to be the ultimate strip head because when I think strip I think more cam, more compression, mechanical roller, and more RPM. Now we might consider a 315 or even larger in a max effort build.

In a 454 that you wanted to terrorize both (street and strip) the 290 cc oval would do some serious damage, but would need a mechanical roller to stay out of valve float and stretch her legs.

Dont get me wrong....Im going to test this on pump gas 91 octane and put the screws to it with a mechanical roller and a single plane intake and I hope to see 650 - 675 HP with a 10 to 1 thirty over 454.....maybe it will make that and maybe it wont but those are my hopes. What I'm more interested in however is what the rest of the curve looks like and that's what holds particular interest to me.

The reality is this would be a perfect head in your tow rig....a 3500 series 454 dually with a small cam and a dual plane intake and headers. It would rock right off idle and make big torque everywhere.....however change up the combo a bit and it will also deliver in your street/strip Chevelle. It has a wide array of applications due to the fact its a small runner that moves alot of air with a very impressive curve from the crack of the valve to .650 lift....covers the entire gambit of any cam you are likely to run in a true 265 cc ideal combination. Our 315 is very similar but made for slightly larger combinations ideally.....you could put one on a 454 and make great power and install the same head on a 555 and also have great success....the key to both is they are very efficient and move a ton of air per their given volume and cross section....thats what makes them extremely flexible and able to cater to many different combos.

-Tony
Let me put that thing to the test:D
 
#34 ·
Don't take the comments so serious Tony, you seem to be getting defensive. I would guess my combo has sold a few pairs of 305's for you.(where's my free T-shirt...:D) Many, many folks have asked me how I do what I do with a 305 cc head when most are running much larger ports.

The proof is in the pudding and I'm sure the 265's and 290's will compete well in the arena they are designed for!

 
#36 ·
I wasn't taking anything you said in a negative fashion at all. And if I sounded defensive I apologize.....sometimes the written word doesn't come across as intended. The largest issue I am concerned with is people not understanding or confusing the target market these heads are designed for. You would be surprised how easily that can happen.

Its all good here and I appreciate your real world input on our product.....its very welcomed actually.

Here are a handful of quick pics I took today. Quality and lighting isnt the greatest but you guys can at least get a better idea/feel for the product.

Cheers,
Tony
















 
#38 ·
Tony, have the head's been rolled any? I have a couple Dart Intake's that matches the GMPP gasket pn 12366985 perfectly ( which incidently is the only exact fit roval gasket I have seen). Will this gasket be applicable to your port as well or will you have your own gasket? I may be a player for your cnc'd version when it is finished. I ask because the Edelbrock head's I currently have are rolled some.
 
#39 ·
Man...I thought I was looking at Edelbrock heads for a second!

Sure you didnt call up 'ol Vic and get castings from him...j/k ;)

Those are gorgeous!




 
#40 ·
Very nice looking for sure.......
 
#41 ·
How would a 265 head fair on a 10.5:1 496 with 252°-260° @.050 .598 solid FT in a 4300 lb vehicle? Mostly street but will make a trip or two to track. Would it support 6000-6500 rpm?

Would I be better off with the 305? I really like the looks of the 265 head as far as numbers go. Actually I would be at 10.7:1 with a 114cc chamber. I only have 91 fuel available here.

Thanks, Jeff
 
#42 ·
It would kick azzz if you wanted to place your emphasis on the street side of the street/strip equation and run damn hard at the track as well.

My air dyno has that combo making 625 ft.lbs and 660 HP (a mechanical roller would have been a fair amount stronger). Note you would have a 112 chamber with the CNC chamber version which is what I based my hypothetical power numbers from....that gets you just under 11.0 which is really perfect anyway as far as Im concerned. You have enough cam to bleed off excess cylinder pressure.

In a 3900 lb Chevelle (race weight) with drag radials or the like, that combo would run 10.90's at 126 MPH with a very modest 60 foot time....with slicks or ET streets it would go similar trap speeds and ET in the 10.70's likely.

Of course it would be a hoot to drive on the street with tire shredding torque at practically any RPM....

Go for it....spring for a roller cam if its in the budget. Its worth 25+ HP in this application

-Tony

Tony, have the head's been rolled any? I have a couple Dart Intake's that matches the GMPP gasket pn 12366985 perfectly ( which incidently is the only exact fit roval gasket I have seen). Will this gasket be applicable to your port as well or will you have your own gasket? I may be a player for your cnc'd version when it is finished. I ask because the Edelbrock head's I currently have are rolled some.
Heads are 24' just like our current rect port line-up with all the valves and geometry in exactly the same position/location.

A stock GM "roval" gasket will work perfectly btw....we used that gasket to shape and position the leading entrance of the heads....after that its a completely different approach to the valves (compared to the Eddy/GM piece).

-Tony
 
#45 ·
I've said all along that the old now long gone cast-iron Merlin VR 290 cc true large oval port heads would be dandies IF brought back to a modern designed life w/ 90 cc open chambers so that out of the box, they would pump up the CR of a stock 454 P/U engine.

And they are true large ovals if I remember right.

pdq67
PDQ,

You just love those "offbeat" scenarios huh.....LOL

Those "dandies" would need some serious re-engineering in their port designs (have you ever flowed a set of those) and it's basically impossible to have an open design chamber at 90 cc's.....not with a 24-26' valve angle. You would have to stuff the chamber full of aluminum (or cast iron) shrouding the valves completely in the process to make them that small (killing flow and killing power).

A flatter valve angle is required (for a smaller efficient chamber) because then the depth or angle of the valve would allow you to not have the chamber so deep which is what ends up eating up all that volume. Even the trick 14-18 degree Big Chief style chambers only manage to displace in the 90 cc range but are much better chambers from a design/functionality standpoint.

As far as a really effective oval design I don't think there is a need to wish for anything anymore....these new heads are going to deliver if the airflow curve and cross sectional area produces the power the numbers would lead you to believe. Not to mention I cant wait to get the green light on the 290 cc project. That head is really going to be something special if my instincts serve me well.

Will keep you guys in the loop on that as this oval port project continues to unfold....

:beers:

-Tony
 
#47 ·
I personally think that when AFR completes the 290 cc version that they should ship a pair to Bob West for testing. He's got one of the more well scienced out oval port combos on this site. He and I both live in the "show me state" and there is no better way for AFR to sell a ton of heads than to ship Bob a set, have him do an A-B test then report the results. If he picks up a couple of tenths AFR would have to immediately ramp up production as the orders would come flying in! If you don't believe me ask Santhuff. ;)

P.S. I grow tired of reading about dyno results with no drag strip performance to back it up. How did the engine dyno and flow bench ever become the benchmark for performance? :rolleyes: LOL Chevelles, Camaros and Novas were born and raised on the drag strip.

My favorite pic of the decade! 1.31 and 1.32 60 foots!

 
#49 · (Edited)
P.S. I grow tired of reading about dyno results with no drag strip performance to back it up. How did the engine dyno and flow bench ever become the benchmark for performance? :rolleyes: LOL Chevelles, Camaros and Novas were born and raised on the drag strip.
I agree and disagree....

Having access to many builds and many dyno's I have never once witnessed a strong piece on an engine or chassis dyno that did not deliver the goods at the track. What I have seen (quite often actually) is some crappy ET's from a few of them because their cars weren't optimized at all for dragstrip performance, but the trap speeds always gave away the potential that lurked in the combination.

All of this of course assumes a reasonably accurate dyno and no shannagans regarding dyno tricks and BS. The combo would have had to genuinely make big power on the dyno....

In fact for me, when discussing cars that spend a good percentage of their running time on the street (which potentially covers more of you folks), I could give a rats azzz about ET (concerning track performance).....the first question from my mouth is what did it trap because that will tell me what type of power that car is laying down and how much of a hard time I may or may not have grabbing a few gears next to him from a highway roll. While I appreciate a car that can do both (ET and trap big #'s), I would rather have the later (if I had to choose one) because once Im more than 100 feet in front of the starting line, thats the sensation thats going to stuff me in my seat the rest of the way down the track. Power to weight is KING, and big power to weight ratios will always yield big trap speeds whether you sixty foot 1.3 or 2.3....you just might lose a dragrace to a much slower car in the opposite lane however as you charge on by him 1350 feet out.....LOL


Regarding the flowbench determining who's fast....well....I have to say thats much more tricky because it relies on alot more data than pure peak flow, but once again, if I was privied to more than just peak flow numbers (CSA, entire flow curve, volume, valve size, throat percentage, etc.), I could tell you with a high level of accuracy whether that head was going to produce average numbers, better than average numbers, etc when dyno day rolled around, but of course that relies also on the rest of the engine combination being well matched to the cylinder heads and thats not always the case. Ultimately, there are quite alot of variables to consider....

However, a good head is paramount in ANY better than average engine combination.....the rest of the package dictating just how much advantage you will take of that heads potential, and ultimately if all goes well and you install it in a vehicle meant to optimize that particular type of power curve you would be hard pressed not to have a very fast combination on your hands....

Ultimately when discussing track performance, what it comes down to simply is that both the flowbench, and the dyno (in that order) are simply good tools to help you along the way.....the information they dispense, if properly used and evaluated, is priceless if you know what you are looking for.

BUT.....if all of this was easy, everyone would be running fast and it takes a well thought out properly designed power train and suspension to excel at the dragstrip.

-Tony
 
#48 ·
Wait, you mean I shouldn;t spend near $800 to get my 781s done up right? Plus hours of my own die grinder time messing them up!? :rolleyes:

I want to be able to literally step off the clutch and nail it, so low end velocity is key. Not a race car at all.
 
#50 ·
Tony. I've got to tell you that underperforming combos with big MPH are what my combo feeds on. :D I've spent the time optimizing my combo and quite frankly, it's designed to be rung out and have it's tonge hanging out at the stripe! However, it's been over 138 so I figure it's making some decent power.
 
#51 · (Edited)
Tony. I've got to tell you that underperforming combos with big MPH are what my combo feeds on. :D
And my C5 on the street does just the opposite.....feeding on lower powered sixty foot monsters.....LOL

Also, don't forget if that underperforming big trap car gets the right tires, converter, or his suspension issues worked out your going to have your hands full!! :yes:

Reminds me of a car that used to clean up on the street a long time ago....60's box Nova that was mini-tubbed. Nothing much to look at and really not a very special engine either but the car had the right converter, gear, and sticky tires and it would leave everyone standing still when the flagman dropped his hands. Only trapped about 116 but it would run 11.50 like clockwork regardless of what street or track it was launched on (that was fairly respectable in the mid 90's on the street). Point is it really wasn't a very fast car but I cant tell you how many faster cars it put on the trailer....LOL

-Tony
 
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