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286 vs 906 vs 452 vs ?? heads

Al K

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In the garage. Under the hood. Again.
OK,I seek the advice of the wise sages of the FBBO. I am not worthy,I am not worthy...

Subject:'62 Max Wedge vs. 906 vs. 452 vs ?? heads on a street driven(with occasional track use) car with a 440. 34-3500 elbows weight. Intended CR of no more than 11:1,but no less than 10:1. Intended cam is Lunati 268 Voodoo(268/276-226/[email protected],.494/.513 lift;could step up to next larger 276 unit),3.91 gear w/ 28-9" tall tires,25-2800 stall converter. 1-7/8 or 2" headers,full 2-1/2" exhaust with good mufflers .
I have a line on a decent-looking set of '62 MW heads,as well as 906s and have a set of 452s on the shelf here. Could I run the 286 pieces "as is"(no porting,just seat work and deck surfacing for straightness) or would a prepped(ported,larger exhaust valves,etc) set of the other heads be a better choice? And yes,a set of aluminum Eddys falls(somewhat) into the equation. I realize that my intake choices are limited,especially if I stick with a single 4-bbl. I think an original MW "NASCAR" intake or a Victor would be my only choices with the 286s,as well as a cross ram w/ smaller cfm(525?) Edelbrock carbs(my preference).
The above is the combination I'd like to run,ANY advice would be appreciated. I'm weighing the costs of various modified "production" head combos vs a set of "stock" 286 pieces. Your thoughts?
 
I ran a full on max wedge in my 68 RR years ago and it worked quite well. I also ran a 383 with the 915 closed chambers and that was great too. I never ran the 452's but I understand some people have had good results with them. The 906 and 915 have the nice short side radius on the floor of the intake port, which I believe helps promote a more laminar flow as the mixture turns the corner into the pocket. The max wedge and 452's have a flat floor which is not as good or might be considered old technology, but the max uses tulip valves - probably to help with the 90 deg transition. The max get's by with sheer volume I think and could be a good choice if you have the ultra rare and expensive NASCAR single 4 intake to go with, or access to aluminum plate and a TIG. I think a nicely pocket ported set of 906 or 915's might do better than the 452, but I have seen flow results that say there is little difference. I suppose the real test is running them and getting the dyno results. Header size for a hot 440 street car you probably want 2" minimum or 2.125" if you run the max heads with the 1.88" valves. might need a small bore notch too but not sure.

In my opinion the only reason anyone paid any attention to the later smog heads (346 & 452, etc..) is because of the availability. Let's face it, the 452 is not designed with performance in mind and they are newer and I believe more plentiful making them easier to find after the older stuff was drying up. The only production BB heads that had any performance minded design were the max wedge and maybe the the 915. Even the 906 is considered an "emissions" head because of the open chamber - at least it carries over the same port as the 915. Now, to add to this head confusion, the old DC stage IV I believe is based on the 452 port and open chamber. I bet this has more to do with a manufacturing decision because ma was making 452's at the time. The difference between the 906 port and the 452 port might have been close enough so they took the easy way out. Finally, if you seen a set of Eddy Performer heads or the Stealth from 440 Source, the intake port has a nice radius on the floor and not flat like the 452, and I'm pretty sure those are not designed with emissions in mind. Based on all this I think I will stand by my statement that the 915 is the best factory head available for performance use with the 906 being a close second. The max is probably the best but typically out of reach.

If you go with an open chamber head use a quench dome piston to preserve the quench area. With 915's or the max keep the piston as flat as possible to promote good flame travel and close to zero deck to keep the squeeze up. Zero deck with 915's and a shim gasket should give you pretty close to 10.5:1 (valve reliefs included). Oooh, I just remembered. The max wedge heads are deceiving because they have a fairly large chamber volume, even though they are a closed chamber, and the volume might be more then the 906 if I remember correctly. That's probably because of the tulip valves. A small dome on the piston might be necessary to get 10.5:1.
 
With the cam you plan on using i would stay away from the max heads and use the 906 or 452s you have on the shelf. But if you want to step it up the maxis would be the way to go. You can get a single 4-bbl intake that will fit the maxi port from Indy, i think its their 440-2 pt/no for a 4150 carb. With any of those old heads make sure you have them maged before putting any work into them. You may also want to have hardened ex seats installed. If you went with the eddy heads (or other alum head)and an 11-1 comp. ratio you may be able to run 93 pump gas. I would look at a little more cam if it was me, but thats your choice. Good Luck, let us know how you make out.
 
As far as heads that are affordable, I would say 915s and then 906s. but 906s are a lot easier to find these days than 915s.
 
As far as heads that are affordable, I would say 915s and then 906s. but 906s are a lot easier to find these days than 915s.

You are looking in the wrong place! I have 6 sets of 915's in my parts room :grin:
 
Why are ya hoggin' all the 915 heads?!ha,ha!
 
You guys rock! Thanks for the info;a set of 915s are also being looked for-to further confuse the conversation. Haven't pulled the covers on the 413;may find a set of the "decent" heads with at least a 1.74 exhaust. More than likely have the small valve units.
I've got the Mopar Muscle mag articles on the flow tests they did on various BB heads;very interesting reading,but almost overwhelming in information. I really want to run the cam/CR/stall/gear combo listed,but am always open to suggestions. I'd definitely prefer a flat-top(with notches if necessary) piston,but want some CR for power. I have access to and don't mind running race gas mixed in with the pump premium.
I do have one other question-for now-concerning valve size. In a fairly strong 440(similar to the proposed combo),are 2.14 intakes and 1.81" exhaust sizes really necessary? Anyone out there running a 2.08/1.74 head with a hot cam,some cr and such,and are you pleased with the results? With a little port work and bowl cleanup,could you still run the smaller valve combination (with the Lunati grind in my first post)without it being too restrictive?
I'm not looking to run 10s here;if this would run mid 12s,I think I'd be satisfied.


...or would I?...Power corrupts,right? Thanks again for any advice.
 
You can use either size and they will work will. However you will pick up some power with the 2.14/1.81 valves. And if you going to replace your valves now is the time to up size. Your head rebuilder can bowl blend nicely and the size increase opens up the shot the valve. Even with the Lunati grind you mentioned it will work fine. Consider it the next logical step if your replacing the springs,guides,retainers, Ex seats, ect.
 
Does that mean the next time I need parts I am welcomed to come and look in your parts room ? :grin:

I'm sorry, did you say something???? :rolling::rolling:

400_F_8955000_ftG9Yc7Ssx5pwCbpT0fEc8ZVEOU7qBIM.jpg
 
Typically, if you go bigger valves you don't need as much cam. I will try the 2.14" x 1.81" in my 915's on a 440 soon and hoping for good results.
 
Well, I am weighing in late here and I am no expert on cylinder heads, but to play devil's advocate here I offer some slightly different info that my cyl head guy agrees with. These articles were produced by Mopar Muscle magazine awhile ago but offer some really good advice on cylinder head selection. You should read all three articles...very well done. I have posted the link and an excerpt .jpg of one of the flow bench results. Good reading!

http://www.moparmusclemagazine.com/techarticles/5115_cylinder_heads/index.html

p39388_image_large.jpg
 
Eddy head flow numbers unported for reference.

FLOW FIGURES
SUPERFLOW 600 FLOWBENCH @ 28” WATER PRESSURE DROP
TESTED BY STEVE DULCICH AT EDELBROCK
LIFT INT #906 INT EDEL EXH #906 EXH EDEL
.100 65 CFM 79 61 70
.200 134 145 107 126
.300 194 209 142 160
.400 217 254 160 188
.500 231 278 167 206
.600 233 291 171 217
.700 232 290 N/A 223
 
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