[Chris]

Hi guys, I finally began to tear down my engine that came with my 71 R/T, its a 383 HP and when I pulled the valve covers off to check the heads the casting numbers, from what the books I have show , it seems to be from a '63 426 Max wedge. The edelbrock manifolds ports didnt line up too well and as you might be able to see from the pictures some of the pistons have valve scores in them. The casting numbers are 2406518. Can someone advise me if these are of value or can they be used on this motor or what should i replace them with? Any advice would be appreciated. Thanks.

[Eddie]

Nope they arent Maxie heads! Those didnt have an exhaust crossover in the middle of the head for intake heat during cold weather driving. Another thing is the port sizes are 25% larger on 426 Max wedge heads. The number I have for Maximum Performance 413-426 Wedges are 2402286 2463209 I think those might be replacement or warranty heads? Since the valves 'kissed' that one piston and the fact that you stated the manifold didnt line up correctly makes me think the heads may have been milled for flatness or compression or perhaps both! I'm not 100% sure but I think those are standard late 70's replacement heads and possibly off a 400/440 truck as I have seen those numbers on some 400 heads.

[Chris]

Thanks Eddie, What would you do with them? Scrap them and go with new ones , I guess if they have hit the piston they cant be used anyway.

[fbernard]

Every search on "2406518" returns "1964 426 Max Wedge". Those are supposed to have 2.08" valves IN, 1.88" EX. You may want to measure them to make sure. They're 86CC.

For example :
http://www.mopar1.us/headcastnumber.html
(Eddie's numbers are for 1962 and 1963, this page says your number is for 1964).

Also :
http://www.cowtownmopars.com/CastingNumbers.html

Anyway, I'd replace those with Stealth or Edelbrock heads, as the work on your iron heads (guides, especially for the valves that hit pistons), valve seats, etc. may cost close tot he price od a new aluminum set.

And chose a piston that is compatible with your valve lift (a flat-top piston, a flat-top with valve reliefs, or a dished piston)

[Eddie]

Same here Fabien, I now have my Galens white books. According to the books the number IS correct for a maxie head 2406518, but his heads have possibly 3 things that the maxie heads dont have.(I cant see the combustion chambers), Closed chambers, 4 bolt valve covers, no exhaust heat crossover, smaller 440 ports. I would keep them or get them reconditioned with hardened metal exhaust seats, bronze guides, new valve job, bowl work ect,, or do what Fabien suggests and get a new set of stealths. According to Frank Adkins book, the numbers I posted above are also correct for Maxie heads? Confusing! But I think he has to fulfill the above critera before they are deemed Maximum Wedge Race Heads. (1962-1964) If he could flip them over so we can see the 2.08 Intakes and 1.88 exhaust which the Max wedges had in production. The chambers were typically relieved as well. But if his combustion chambers are open then it's a common '440/400/383 head used from 68-79

[Chris]

I'll take more pictures of the bottom side and put them on tonight when i get in. Thanks.

[Eddie]

Chris, here is an interesting article concerning the max wedge heads. Note the lack of an exhaust crossover for the intake manifold heating and cold weather carb operation. I was wrong about the valve covers. They appear to be the 6 bolt same as our 'traditional 906 heads. Also note the closed chambers and huge ports. I'm not a maxie expert. Just want you to get the correct info. Sorry if I'm wrong however!

[dave-r]

The fact that the casting number starts "24" tells you straight away that this is a head that was cast in 1962-64.

The '67 head started "27"
The '68 head "28"

In the 70s the head numbers started "34" and then "37".

Last of all are your late 70s heads which started "40".

My parts book has 2406518 down as the '64 Max Wedge head.

[dave-r]

Look how close the ports come to the surface of the head. There is not a lot of meat between the bottom of the port and the deck.

A stock 440 head would have thicker meat here. The stock head is thicker between the ports too.

Yep. I would say these are 100% Max Wedge heads.

[dave-r]

These are my ported 906 heads for comparison.

Note that the Max wedge heads are bigger all round but are not raised at all.

[Chris]

Thanks for all the input guys. Here are the pictures of the bottom side.

[Chris]

If these are 64 Max wedge heads, from what i have read they cant be used on this motor anyway because you cant get a manifold to fit them properly. If this is the case what could i get for them?

[fbernard]

If these are 64 Max wedge heads, from what i have read they cant be used on this motor anyway because you cant get a manifold to fit them properly. If this is the case what could i get for them?

You could probably find a compatible intake manifold in Indy's catalog.
You may have to use manifold spacers (flanges that allow the use of a RB manifold on a B engine).

[Chris]

What about the valves hitting the pistons?

[fbernard]

What about the valves hitting the pistons?

As I already said above, you need to change the pistons.
(Really) thick head gaskets could work, but they will screw up the compression ratio, which will screw up mpg among other things.
Besides, thick enough gaskets will cost as much as a new set of hypereutectic pistons (around $ 250).
You'll need new rings, a full gasket set, and new rod and mains bearings may be a good idea while you're at it.
Before buying anything, you need to measure cylinder bores, and bearing clearances.

[dave-r]

What about the valves hitting the pistons?

As I already said above, you need to change the pistons.

And/or the cam. It might have a lot of lift which would not help.

[Eddie]

If these are 64 Max wedge heads, from what i have read they cant be used on this motor anyway because you cant get a manifold to fit them properly. If this is the case what could i get for them?

A lot!!!

[Chris]

Thanks for all the advice, I guess i'll try to find out what somebody will give me for them and go from there. I had planned on putting a stroker kit in it and maybe i'll get those new heads like you suggested.

[dave-r]

Just been reading about these heads. These particular heads would have likely been on a 1964 Dodge Ramcharger 426 Stage III. This was the last and most developed version of the Max Wedge head.

After this they started using the Hemi in Drag racing from the 1965 season on.

[Eddie]

Here is a site dedicated to the mighty maxie package. They also note the abscence of a heatcrossover and the fact the exhaust valves are 1.88" much larger than even our 906's 1.81 http://maxwedge.com/orangemonster/orangemonster.html those heads may be worth big bucks Chris!!!

[dave-r]

The '63s definitely didn't have a heat crossover. But I have not been able to find an image showing the '64s.

[Eddie]

The '63s definitely didn't have a heat crossover. But I have not been able to find an image showing the '64s.

Thats the only part that confuses me Dave. Thats why I called em the way I did. Another thing, are those exhaust valves 1.88's they look a bit small to me. The maxie heads filled up those combustion chambers pretty good.(Hence the name maximum wedge) I think they even relieved the chambers beacause of the relatively 'small' bore size of 4.25. I 'm not saying they arent max wedge heads, it's just that there are some unanswered questions. Also, are those chambers closed? It's hard for me to tell with just the pics. They look lower on the 'quench pad' than the gasket line. Closed chambers are even I believe. Like the 915's of 1967

[Follicly Challenged]

From the Chamber photos, those look like 64-66 closed chamber 383, "2406516" heads, W/2.08" 1.60" valves.

Big spacing between the Intake & Exhaust.

Intake Ports too small, not near enough Pushrod offset, stock rockers don't work on MAXI's

Casting boo-boo on the "6" & "8"

Also,
Intake port windows, not near Tall enough for Maxi's.
You'll know when you have Max-Wedge, they're just huge Toilet holes.

Just my opinion only, NOT max-wedge of any kind.

[dave-r]

You are right.

Looking at the number on the bottom of the head again that is a 6 on the end and not an 8.

Oh well.

[dave-r]

Should have known you would be right all along Eddie.

[Chris]

Thanks for all the input. I dont have the proper tools or Know how to measure properly, but the valves when measured with my tape measure accross are 2 1/8" and 1 5/8". I still cant tell if it is an 8 or a 6 but if they are the 65 383 heads would they be worth using on this motor? Even though my dreams of making big bucks for the Maxi heads are crushed.

[Eddie]

Well Chris to tell you the truth, by the time you invest in hardened exhaust seats, 2.14 Intakes and 1.81 Exhausts if they havent already been done, and by the time you mag check them for cracks, gasket match or slight porting, ect you will have spent more than a new set of 440 source heads and not flow as much as the new alloy heads offer out of the box, you also wont have the same flow balance, you dont have closed combustion chambers so the positive effects of squish and quench wont be realized which will allow for a full point more of compression without detonation that prevails in open chamber designs, thats why the OEM uses closed chambers exclusivley. Without resorting to special pistons made for open chambers, you'll be dollar down and still not match the performance of a new set of alloy heads. Head porters dont work for free, and to develop the ports without a flow bench is haphazard at best.(Although MoPar used to offer porting templates if you have your heart on doing it by your self). I was in the same boat as you when I built my 440 sixPack engine. I decided to shelve my 906's for a new set of Eds heads. Glad I did. The engine is a torque animal! Oh and thanks Dave. We can ALL learn from the discussion.

[Chris]

Thanks.