real surprise out of a worn out 150...

[150aintenuff]

went out with a 24 chopper i bought for a project 225 i bought to baseline it on the hull to see gains on my 20' fissin hull, and the little 150 shocked the hell out of me.... the normal prop is a 21P MI wheel rapture and it runs 48-49 mph at 5200-5400 rpm prior to rework i saw 52 @ 5600 once but that was in middle of winter totally empty, with 10 gal of fuel...... well yesterday in 85-90 degree heat that 150 rolled the 24 chopper 5100 rpm at 53 mph witch totally shocked the hell out of me.... 1 that the chopper even plained off mounted as low on the boat as the engine is... the cavitation plate is 1" above the bottom. no jack plate either.... I was only expecting to see about 4600 RPM... really surprised me... now to convince the old man to add a 12" jack, solid mounts, and hydrolic steering... was fun to watch the pilt tube speedo... at 47 mph indicated it would lift out of water and drop to like 20 mph so the boat was up on the center pad more than ever before.... needless to say it was shocking as heck........

any one have any other ideas as to why it worked so well mounted low, on transom,
I thoght choppers would only work effectivly with propshaft height close to even.. but i know i was slightly at least surfacing.... had a 20' long cowl high rooster untill boat lifted aove 45 mph.. then roost settled to about lower pan height.... all in all worked well for what power i have.....

[150aintenuff]

79 views and no comment???

[Scream And Fly]

Actually, Chopper props were not originally designed to be surfaced at extreme transom heights. They were ideal for situations where the engine was only a few inches higher than normal. The staple of those props was awesome bite and holding while giving a lot of lift. Remember that the Chopper prop has been around since the 1970s - long before nosecones with low water pickups were readily used.

Greg

[150aintenuff]

lern sumthin new every day......