1.92"/1.60" Magnum R/T Cast Iron Heads, here are my initial results:
LIFT-----ASCAST--------PORTED
---------IN/EX----------IN/EX
.200"--135.6/110.4---148.4/111.8
.300"--194.9/154.9---208.7/155.3
.400"--227.4/173.5---243.2/189.1
.450"--233.9/177.3---252.5/194.6
.500"--239.4/179.4---255.6/197.7
.550"--244.9/180.8---259.1/199.8
.600"--245.0/181.8---268.4/201.2
.650"--245.0/181.8---276.0/203.2
.700"--241.5/183.2---281.2/203.2
I still have some chamber work to do, so I expect #'s can be just a hair better on the Ported Cylinder.
Not bad for a 1.92" valve. The ported .300" intake flow is the highest # I have ever seen out of any SB head ever on my flowbench. So to say the low lift is good, would be an understatement.
The exhaust is ok for what it is. MP IMO goofed up and put a magnum short turn in it instead of the true W2 turn. That coupled with a smaller and improper port exit shape will not allow it to flow quite with a true W2 head in the high lift #'s.
I'd like to see a 2.02" version to see what the difference in flow would be exactly.......
Overall, I think this may be one of the best SB cylinder heads on the market today for the $. Mancini has them for $429 each bare. The advantages of these heads may be too numerous to list, but here are some hightlights:
8mm I/E valve stems...
63 cc CLOSED chambers (good for flat tops and Quench motors)
Stock Exhaust Bolt pattern
10 bolt Magnum Valve covers, with MILLED VC rails (ie. NO LEAKS)
Re-enforced decks with external stiffening ribs
The intake port Valve Job, out of the box was in my opinion, probably the finest VJ I have ever seen on any head EVER. I sat there and stared in bewilderment when I looked at it. 6 angles, and every cut is the perfect width, perfect angle etc. BLEW ME AWAY for a MP part right out of a box. These heads are cast at the same foundry as the new W-2's, but I have had a pile of new W-2's in my hands and whoever did the VJ on these heads is not who is doing the W2 stuff. Absolutely no reason you could'nt bolt these heads on and run right out of the box.
And my favorite:
TRUE Hardened exhaust seats installed from the factory. NOT induction hardening. These are actual pressed in Hardened seats..... not only are they hardened, but the shape of them was created for airflow. ie. they are a rounded seat right up to the 45* seat. I have never seen seats like these before. Perhaps Dwayne etc. can shed more light on them? As soon as I saw the exhaust seats when I pulled the head out of the box on Thursday I was blown away.
I can't say enough good things about these heads. I still am in LOVE with the Large Port Commando for an Aluminum street head, but these have the Iron field covered. They will never flow as good as a W2 due to the pushrod pinch restricion, but there are more things to think about when trying to make power than absolute raw flow #'s. The short turn on these heads is an excellent design once again right out of the box, Brett will love how much the short turn angles down AWAY form the common intake wall. Whoever designed this head at MP, was earning their $ on this project. It took very little reworking or moving of metal from the short turn, (or anywhere for that matter) to get the #'s you see above. I am going to try to play with the short turn a little on another cylinder, but I think All I can do is hurt low lift flow from here.
OH and BTW for those of you who's minds are churning, YES these will bolt right on an LA block, you will just have to pushrod oil the rockers with an AMC lifter and run a Magnum intake manifold.
And Patrick, don't even bother asking for intake runner volumes as I hav'nt CC'd it yet.
Good God I only got the head 2 days ago LOL But I know you will want to know that, and CC'ing it is in my plans if I ever feel like it here tonight.
I think these will make "moparheads"'s little 348" stroker motor scream.
