Speedmaster aluminum block

[Steve.k]

Pro stockers im betting 1-2 at least a season.Likely before each major event if you wanna have the edge. But cant use in p/s so not sure what class he was talking. Depending on car and set up that hp will change. As with the 65hp on Daryl's rail. The new track boss is made with a different grade alloy. Tim noticed that when machining it flaked more like cast. Thats why the comparison now on this would be interesting to see.

[blykins]

Maybe, or they switch engines out.

[blykins]

IIRC, David Reher said they lose about 40 horses on their Aluminum block pro-stock stuff. Also said they run a different cam in those deals to spin them a little more to make up the deficit.

Considering those are around 1300-1400 horsepower 10,000+ rpm combinations.. seems like pissing into the wind to pointlessly argue about a lower power application speedmaster block being down on power just because it's made out of aluminum. But.. some guys like to constantly pick turds out of gnats asses so here we are again.

Wasn't born yesterday either and I'd take my 357 cast aluminum World 18 bolt SBF block over any OEM cast block any day. Even if it's down 20 horse.. who gives a gnats ass when weight reduction negates the loss and helps me turn faster.

So if RM can add another camshaft to an aluminum block engine and get 40 more hp, why don't they do it on the cast iron blocks and be 40 hp ahead?

I know that both Keith Craft and Blair Patrick have seen 30-40 hp differences between cast iron and aluminum FE block combinations at the 700 hp level. That's 5%. I've also seen similar discrepancies on some of my FE stuff.

[Steve.k]

Brent it should also be noted that Tim was in contact with total seal and they were discussing ring packs on our bigger bore size.They mentioned they do testing continually on both. The gap was way wider than what they see now in current line of alloy engines. Im not certain what they were using but its interesting.

[blykins]

Brent it should also be noted that Tim was in contact with total seal and they were discussing ring packs on our bigger bore size.They mentioned they do testing continually on both. The gap was way wider than what they see now in current line of alloy engines. Im not certain what they were using but its interesting.

What do you mean? Can you explain further?

[Steve.k]

Total seal performs testing on their rings on a wide variety of engines.They used to see a wide hp discrepancy from alloy to cast. However he said the new engines they do not see as wide of gap. Im assuming they are testing oem style engines as this is bulk of sales i would think. Its interesting to hear.

[blykins]

Total seal performs testing on their rings on a wide variety of engines.They used to see a wide hp discrepancy from alloy to cast. However he said the new engines they do not see as wide of gap. Im assuming they are testing oem style engines as this is bulk of sales i would think. Its interesting to hear.

Possibly OEM stuff.

The aftermarket stuff is all over the place.

I would ask them to qualify their comments.

I wonder how Dart's "RMR" alloy compares to the C3A1 alloy? Anyone know? The Dart aluminum blocks give up horsepower from what I've seen too, in the 9.500" deck aluminum versions. Never had a porosity problem from Dart though.

[Steve.k]

No one uses the c3a1 we use. Everyone else 356-t6!

[blykins]

Dart doesn't. They use a "proprietary" alloy. Not 356.

[swampbuggy]

Steve....the question on alum. Pro-Stock block was most likely IHRA or some other sanc. body that allows alum. alloy blocks. Mark H.

[swampbuggy]

Steve...what are the excellent attributes to c3a1 over other alum. alloys Mark H.

[Steve.k]

It has higher heat capacity and is denser compared to rest. Only used in areospace up till now. http://www.eckindustries.com/portals/0/ ... lSheet.pdf

[blykins]

Need to compare the coefficient of thermal expansion between the two.

C3A1 is 20.6 to 28.6 mm/m/K.

356-T6 is 23.

[Steve.k]

IMG_2770.PNG

. Here. Thats alcoas graph.

[Steve.k]

You see by using a product 20-26 percent stronger our hopes our to reduce this difference. Thats why I'll perform a test on all same components. Then we know how close we are. Also the cast block will have even thicker sleeves than alloy. So it will be a good test. In cleveland land we are not accustomed to .200+ cylinders.