A while back it was questioned whether my 200 made the 450 hp I had in my signature. I find it funny that the longer stroke 250 or custom stroke 250 is not questioned. Sure a 269 will make more torque at a lower rpm - great for street use - but a higher revving 200 will make the same horsepower. Here are some reasons:
1) The biggest restriction of the log is the valve bowl and throat. Walls are too thin to be ported out to make a huge difference.
2) Peak horsepower at 4800 for the 269 is the same cfm as a 200 at 6456 (is my math correct??). Geezer typically runs his at about that rpm.
3) The engine that we have dyno proof on (Walt's) is using a space saving, on center turbine housing (robs some power) with a faster spooling, smaller AR than what I used, there again robbing a little more power.
4) A 200 crankshaft is 20 lbs lighter. Rods are also significantly lighter (less inertial lost hp).
I ran a little less boost but I think the above should equal that out. Engine ran through the traps at 6800.
I think Walt's set up is amazing. He fixed the log's fuel distribution problems.
This is simply about the lowly 200 making the 450 hp I claimed.
There's no doubt the 250 is a stronger platform to build off of. Easy to bolt on heavy duty drive lines. It is also about 80 lbs heavier.
1) The biggest restriction of the log is the valve bowl and throat. Walls are too thin to be ported out to make a huge difference.
2) Peak horsepower at 4800 for the 269 is the same cfm as a 200 at 6456 (is my math correct??). Geezer typically runs his at about that rpm.
3) The engine that we have dyno proof on (Walt's) is using a space saving, on center turbine housing (robs some power) with a faster spooling, smaller AR than what I used, there again robbing a little more power.
4) A 200 crankshaft is 20 lbs lighter. Rods are also significantly lighter (less inertial lost hp).
I ran a little less boost but I think the above should equal that out. Engine ran through the traps at 6800.
I think Walt's set up is amazing. He fixed the log's fuel distribution problems.
This is simply about the lowly 200 making the 450 hp I claimed.
There's no doubt the 250 is a stronger platform to build off of. Easy to bolt on heavy duty drive lines. It is also about 80 lbs heavier.