Heckeng Posted September 27, 2009 Share Posted September 27, 2009 I'm not sure if any of you have been following this on Team Chevelle, but Tony Mamo at AFR has finally come out with an Oval Port head for BBC. These heads have 265cc intake runners compared to BBC stock rectantular port volumes of 325cc. These things look amazing, and I REALLY REALLY want a pair! I've been eyeing the Brodix RaceRite ovals (270cc) for quite a while, and they are awesome heads (Bob West runs them and has his chevelle in the 9's!). But, there is now a flow test for these heads comparing them to the RaceRites and they whoop them amazingly! Here is the flow test from the Chevelle site: 4.530 bore 28" clay radius inlet no pipe The reason for the 4.530 adapter is because that is what I flowed the Brodix on .050 - 39.4 / 32.2 .100 - 75.6 / 64.4 .200 - 168.0 / 144.5 .300 - 252.4 / 196.4 .400 - 307.3 / 232.5 .500 - 339.4 / 248.5 .600 - 350.7 / 254 .650 - 343.6 / 255 RR OVAL 270cc port CNC chamber same conditions .050 - 42/33 100 - 77/65 200 - 152/118 300 - 224/147 400 - 283/178 500 - 318/205 600 - 344/230 700 - 347/248 EDIT++++++++ Couple of other things to add The AFR has a 2.19 intake valve The Brodix was 2.250 Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted September 27, 2009 Share Posted September 27, 2009 what size are the chambers??? Quote Link to comment Share on other sites More sharing options...
CrazyDavey Posted September 28, 2009 Share Posted September 28, 2009 I don't know Scott, dropping down to 270 is a pretty radical change. I know increased velocity sounds good but at some point the breathing is going to be an issue for a big motor. JMO but I don't think I'd go below the 290/295 range, it's a good middle of the road size that still allows future growth for your motor. 325's are to big but 270's might limit your motor too much. As Sam has opened the door I think the chamber size is more critical, with your current setup compression is your friend. I'm guessing your current heads are 119's, if so you should see if you can get down to some 112's or 110's and bring it up close 9:5 (that's still pump gas), that with 295's will really wake up your motor.....some guy may be in the 9's but it's a totally different setup.....again JMO.... Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted September 28, 2009 Share Posted September 28, 2009 I don't know Dave, I know a guy making 650hp on pump gas with ported factory oval ports some compression would do wonders for you Scott, some 110cc chambers would jump you approx one point Quote Link to comment Share on other sites More sharing options...
CrazyDavey Posted September 28, 2009 Share Posted September 28, 2009 I don't know Dave, I know a guy making 650hp on pump gas with ported factory oval ports some compression would do wonders for you Scott, some 110cc chambers would jump you approx one point my point exactly Sam..the 295's I'm talkin' about are oval with 110 cc.....I think on the low end the shape does make a difference.... Quote Link to comment Share on other sites More sharing options...
Heckeng Posted September 28, 2009 Author Share Posted September 28, 2009 After reading all of the threads about the oval port 270cc racerites and who is using them, even on 496's etc, I think that they would be about perfect for the 454 size. AFR claims to have made these heads for street 454s with smaller hydraulic rollers in mind (under .650 lift or so), and those flow numbers beat any GM casting ever made, oval or rectangular port. So, if you can have more flow along with higher velocity, it is a win/win. I think they come with 114cc chambers. I agree some compression will help my engine, but I think the smaller runners would do more. Just my opinion though! Quote Link to comment Share on other sites More sharing options...
CrazyDavey Posted September 28, 2009 Share Posted September 28, 2009 well Scott you'll just have to get out the checkbook and give us a report!!!! ...they use sommething very similar on the 502's (295 with 110cc semi opem). It's just a matter of where you want your power and for street what you're talking about makes sense. For an all out motor working above 6500 then open chamber and bigger runners are going to start being more favorable....I've used both in different applications....my 7000+ motor really liked the big heads..as you JMO... Quote Link to comment Share on other sites More sharing options...
Heckeng Posted September 28, 2009 Author Share Posted September 28, 2009 You are right on many counts there Dave! If I had the money, I would own a set of these guys and test 'em for you all! Since I'm going to keep my Hydraulic Roller cam, I plan on being done by 6500 as well. If your motor liked switching to larger ports, I would look at the flow numbers. These little heads flow more than my big port heads, so I would see an improvement in flow through the whole power band. Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted September 29, 2009 Share Posted September 29, 2009 according to AFR web site... the combustion chambers are 107cc's as cast, 112cc's with the CNC'd option I think they would work great with the cam you have Quote Link to comment Share on other sites More sharing options...
Mike 57 Posted September 29, 2009 Share Posted September 29, 2009 They also make a 290 cc version they say kills the 305 cc rectangular. Exhaust ports are raised .375 Quote Link to comment Share on other sites More sharing options...
680HPStroker Posted September 29, 2009 Share Posted September 29, 2009 I'd be interested in seeing how these AFR heads worked out for small displacement BB's(less than 500 CID). I was a little sceptical of using rectangular port anything for a mostly street car, but my AFR 315 CNC rectangular port heads have 119 chambers with 315 runners and on my 489 with 10:1 compression they are awesome with either a hydraulic, or a solid roller cam. The right combo makes all the difference. Quote Link to comment Share on other sites More sharing options...
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