Is there a good enough difference between the 2 to consider to go with RR heads over standard 23* heads? I was thinking about going with Brodix or Dart 227 CNC heads for my 406 sbc, but then got to looking at the Edelbrock Chapman heads and was wondering about the bennifits. It would have a single plane intake with a hydro roller cam with 230-240* intake and looking to get as close to .6 lift as I can get.

My only concern is that the port velocity would be less with the 238cc Chapman heads compared to the Brodix or Dart CNC heads. I was thinking about the AFR RR heads, but the Chapman heads dont require offset lifters and cost a little bit less.

Thanks
Jeremy

 

Does Edelbrock definaition of "High Port" equal that of other companies with their stated "Raised Roof/Raised Runner" description? I always look at these heads myself for future projects but I'm not even sure. I'd love to do the Chapman heads on a 406 like you're doing. Check out the flow numbers.hehe Pro Action has 18 degree and 23 degree heads that look awesome also. MAybe someone else will chime in here.

 

I believe with Pro Action, any thing other than standard 23* heads, are off set rockers.

 

Keep looking there is one 18 deg head that uses standard SBC valvetrain parts.

Alot of this depends on what you need out of a head. A RR is only really needed if you need stupid flow. I've seen some 23 deg stuff go well over 330cfm. The porter and the right head will get you most of what you need.

Bret

 

Stupid Flow? Yeah, I prefer smart flow myself. LOL. Just kidding.

I agree that you can get big numbers from raised runner heads. We recently got a set of Pro Topline 23 deg, RR heads to flow 340 cfm without breaking through the casting anywhere. Those heads made almost 780 hp on a 406 sbc with very little tuning time. Just a couple jet changes and some ignition timing adjustments.
One good thing about the raised runner heads is the nicer short turn radius and improved wet flow characteristics over standard runner heads. If you can afford to get the heads and matching intake I would run them every time. They would make for a killer street engine if you kept the ports small and used a fairly small cam.

 

yup...starts with bro and ends with dix

 

What do you guys think about those brodix heads? I was looking at using them on a 396 build up but thought the intake runners were a little to big for street use. I like the fact that you can use 23* valve train parts thou.


Mike

 

well there are pros and cons of them.

Pros
-18 degree
-more flow in the lower ranges and higher (low-mid is more imoprtant)
-23* standard rocker stuff


Cons
-not the best 18* heads out there
-the standard 23* valvetrain parts kinda limits its flow potential due to port placement
-has 18* spreadport exhaust flange (custom flanges and/or headers)


----you can still make a lot of power with these heads and if my memory serves they only have a 244cc intake port. Which if you compared that a 23* port it is more around a 220cc-230cc type port because the bulk of the cc in the port of the 18* head is in the length and not the width. Kinda like a rectangle instead of a square if that makes sense. If you have the ability to use them i would. I mean they aren't that expensive, they flow well outta the box and doesn't require expensive shaft stuff.

 

I ran raised runner heads with stroker combination that indeed was the best choice ever made vs 23 deg setup. I'm not sure as to what setup your looking at but I my self prefere to have my power band comming in at the higher rpm range. With the right combination running RR you will more torq than you will be able to handle. Most don't understand that with big stroker small blocks with compression and even large solid roller cams being used on the street are far from dogs assuming correct converter and what not.

Just to give ya a idea of what I'm talking about I ran a 440ci EFI NA small block with 18 degree heads in my Z for a short time on the street and it was the most fun I had with the car. With 315 drag redials at 40 to 50 mph you could nail the gas pedale to the floor and do block long burnouts but the tires would break loose even at those speeds. Lastly one other example I have a buddy with a Pro Street 65 GTO street car that runs a 632ci Big Chief head motor with a solid roller cam over 1" in lift not to mention the heads flow over 510cfm at 950 lift flowed at 28"! Now if you have never seen a set of Big Cheif heads and the port volume they have you should because they are huge! Just to give ya idea hold your hand out and with your four fingers side by side you could put them into the intake runner all the way up to your nuckles. Now thats a port that flows! This motor at peak power made 1238hp but at 2000rpm the motor was already making 980ft lbs of torq. You see these big motors either small block or BB will give ya more torq then you think. I just think if you pass up the RR for the 23 degr. you will be kicking your self, its well worth the extra cash for lifters and valve train.

The brodix are very nice heads as are the others you listed but one word of warning be carefull with AFR heads because the flow numbers are inflated at least mine where and the CNC port work SUCKED! purchase them bare or from a good head porter.

I had to mention these heads because I love everything about them and the pure fact that flow numbers in the 400 plus cfm range are being had. That equals MAJOR HORSEPOWER!

DART'S SMALL BLOCK CHEVY LITTLE CHIEF 11 DEG. CYLINDER HEADS

Good luck!
I have heard and read the many debates from all different sources about the smaller conservative intake ports with street motors is indeed the way to go because you end up loosing so much bottom end. Well, I guess that would hold true if a person was installing a 227 runner head on a stock motor but if your building this from top to bottom

 

I just thought I would point out that the Brodix head can be ordered with a stanard Ext. pattern. It does limit port size but can be done.

I am planning on using one of the -12 castings for my build up. Any one have any insight on this?

 

Guys, maybe I'm way off. If so, I'm willing to learn. But the large port motors I have driven on the street were quite unpleasant. Sure, a given motor might make good torque at relatively low rpm. But that's not the problem. It's throttle response under low rpm/small throttle opening conditions. Like trying to drive along in slowly moving traffic with lots of small variations in speed. Large port (admittedly a relative term) heads are really herky-jerky under these kinds of conditions, no matter how much torque they produce at a given rpm and WOT. An automatic with a loose converter is of some help in taming this kind of combo, but like all loose converters make a lot of heat, noise, etc.

Anyway, Jeremy really hasn't said what he plans to use the car for. So I may be way off base. If it's a car that's a toy, driven a bit on the street for grins and giggles, it's one thing. If it's a "real" street car, it's something else.

Rich Krause

 

I was planning on it being a daily driver. I know that Bret liked the AFR RR heads, and I figured that maybe the Edelbrocks where worth a look at since they cost less. Granted they have a larger port, but I didnt know how much that larger port would make a difference. I was planning on using a ~230* duration on the intake on something like a 112 or 114 LSA in a 400 sb.

 

Rich for me and the cars I have worked on the Larger TB has caused what you are typing of. No matter what cam i have used the Larger TB has caused this. Then again I refuse to give up the 25RWHP my 58mm TB gave me on back to back dyno tests

I have driven this car every day for years. Back when I had the blower on the car it was the ONLY car I had. Only recently did we retire it two second car dutly. The car now has a fair sized cam and over 400RWTQ to go with the 400RWHP. When the Water pump went out on the wifes car(95 Z28) we used it as our shared commuter 65 Miles a day for two weeks. I must admit the 15MPG did hurt over our normal 20MPG we get in the wifes car. Rush hour traffic can suck!

The plan for using the -12 Brodix heads will fit fine in our plann's. Goal? Low ten second car that still carries every power option GM sold the car with Then drive it in that same rush hour traffic for weeks at a time when needed I am just hoping NHRA does not change the rules for 10.00+ Was hard enough to put the Roll bar in it. I could not put a cage in it right now. Right now anyone can get in the car and drive it...A cage would ruin that.

 

Ive been looking into the Brodix 18x heads myself for my buildup. The low lift numbers are GREAT looking, as well as the higher lift numbers. The exhaust numbers are pretty darned nice as well. Seems like an all around good head. I hadnt thought about the custom pistons though, but Im thinking with the dished pistons (turbo'd motor) I would need, it shouldnt be such a problem. And yes, they do offer them in the standard exhaust bolt pattern.

The only thing Im worried about would be issues with the intake. As I am not going to be able to afford a nice carb converted to EFI or a sheetmetal intake for a while, I was wondering if a modded LT4 intake could be adapted? I havent gotten to look at a set of the 18x heads in person or in pictures so I wouldnt know. I am only 45min from the Brodix factory, so I could take a trip up there to have a look see and talk to a few folks about them. I could even have Brodix convert them for reverse flow cooling for me.

Kyle

 

You could definately get a LT4 intake to work it would just take some time lining up the flanges and port matching it.

I've seen some good flow number out of a set of ported versions of those heads. 360cfm is not out of the question with a very good head porter

Bret