MMS205 results thread...
 

I have been in love with these heads since I first heard about them, and all of the old school AFR205 results speak for themselves.

Has anyone dyno'ed or tracked a set of these heads?

I am particularly interested in results with the 3.898" bore, but any/all results are definitely welcome.

Ultimately I want to use them on a 372ci "square" stroker, using a GenIV 3.898" iron block, and a custom 3.898" Magnum XL crank. But that doesn't really mean anything, right meow.

.....................................crickets..... ..

David, i say go ahead and build it. Some of the OLD heads are better than this new crap.

I would use the AFR head on something like an LS1 due to the 205cc runner.
It would be a killer on this engine although I would rebuild the LS1 with better internals as these engines are kind of lazy and don't like to rev that well.
Rebuilding them fixes that right up.

The MMS 205 is a completely different head from the original AFR 205 designed by Tony back in the day.
The new (comparatively) MMS 205 starts as an AFR casting with a 180 cc port before Tony"s CNC program, and
utilizes a 1.97" Intake valve and was/is designed for the 5.3 liter bore size.

Agreed :)

I was hoping that someone on here would have used them by now. I know FastBrick had a set for a 5.3 he was building, but I can't find anything that signifies he completed it.

In the MMS223 Sportsman head introduction thread, Tony says the MMS205 flows 298cfm on a 3.78" bore, some ports flowed 300, but he felt 298 was a better average. I believe in the same thread, Tony says that the MMS205 has a ~82% exhaust ratio. This is essentially all the information I can find without bugging the man himself.

I would love to be in a position that I could feasibly build the square 373ci (3.9"x3.9"), but that just is not in the cards right meow.

Mounting them on a 3.9" bore will only increase flow and coefficient of discharge. And a 3.9" stroke will help put some pull on the heads. There are plenty of intakes that can flow everything these heads ever will, so with the proper spec'd cam, this thing should comfortably max out everything the heads are capable of delivering.

That's true.
Very efficient setup.
Tony did tell me for an LS 408 on a 4.030 bore the best size head to use is a 245cc.