tartle said:
by the way I thought it was a 100 litre engine that would deliver 5,000 hp; with 4,000hp coming from the 61 litre version?
Let's have a chat about this. I have never been clear on the 61L, 75L and 100L engines. I have seen them called the Exe 61, Exe 75, and Exe 100. I have seen both the 61L and 100L called Snowden. Some sources give no mention of the 61L, while others give no mention of the 100L, and most give no mention of the 75L. It seems like the 61L achieved some "off-paper" development, but the 100L did not. I have seen numbers for the 61L from 3000-5000 hp and 4,000-5,000 hp for the 100L, but no numbers for the 75L.
It makes sense that the 61L would produce 4,000 hp (or maybe even 3,500) and the 100L 5,000 hp (or maybe more). In comparison...
Exe - 4.225 x 4.0 x 24 = 1,346 cu in (22.1 L) 1,200 hp (54.3 hp/L)
Pennine - 5.4 x 5.08 x 24 = 2,792 cu in (45.8 L) 2,750 hp (60.0 hp/L)
61L - 5.4 x 5.08 x 32 = 3,723 cu in (61.0 L) 3,000 hp (49.2 hp/L) seems low, 3,500 hp (57.4 hp/L) seems reasonable and 4,000 hp (65.6 hp/L) seems a little high
75L - 6.4 x 6 x 24 = 4,632 cu in (75.9 L) ? hp
100L - 6.4 x 6 x 32 = 6,176 cu in (101.2 L) 4,000 hp (39.5 hp/L) seems low and 5,000 hp (49.4 hp/L) seems reasonable
In looking at the numbers, it seems the 61L was a 32-cylinder Pennine (admitted oversimplification). The fact that they share the same bore and stroke (and probably cylinders, pistons, rods, sleeves, etc.) gives some credence to there being some development of the 61L engine. The 75L on the other hand, was an enlarged Pennine, and the 100L was a 32-cylinder 75L (oversimplification again). Could it be that the 61L was to be a 3,500 hp engine, the 75L 4,500 hp engine and the 100L 5,500 hp engine?
Which is the Snowden? Would the 61L be the Snowden because some work might have occurred? Would the 75L or 100L be the Snowden because they were a different bore/stroke than the Pennine and Exe? Or would Snowden be the name of the next "X" engine regardless of what size it was?
Ah, the madness of it all. Anyway, I changed the 61L "Snowden" output to 4,000 hp, even though I think 3,500 might be a more realistic number. 5,000 hp was certainly too high.
Thank you,