Looking for prop ideas, checkmate 253 LS power
 

Looking for some prop advice/input for my Checkmate 253. Power is a 408ci LS2. It makes peak power (573hp) at 6300 rpm, so I have my rev limiter set at 6500. As far as torque goes, it makes peak torque (568 lb-ft) at roughly 4300. However, it starts making 500 lb-ft at 3000rpm and doesn't drop back below 500 lb -ft till 6000rpm. So I know it has the power to push the boat, its just a matter of getting it to the water properly. My main issue is the amount of weight I took out of the boat with the new motor. The LS2 weighs 560lbs fully dressed. The 454 (all stock 310hp carb'd) weighed over 1000lbs. Now the boat site 2-3 inches higher in the back at rest than the exact same boat with a big block. These hulls have always ran best with a Bravo 1 prop that provides a lot of stern lift. Well, to me it seems that stern lift will no longer be an issue with all that weight out of the transom, However I could be wrong. As of now, the hull weighs approx. 4000 lbs with the motor in it, not including fuel. I have only had the boat out a couple of times with the new motor with two different props, both Mirage +'s. I decided to try them because one, I had access to try them for free, and two, I knew the 3 blade would provide more bow lift. They were a 23p and a 25p. They both seemed to do ok out of the hole, not as good as the bravo that was on the boat prior, but that's to be expected. The problem came when I started to give it some throttle and trim. As I started to trim it, the rpm's came up and it was accelerating, but when I turned around, I was shooting a big ass rooster tail. I only ran it up to about 4500 rpm and backed out of it because the motor is still pretty new and I was also concerned about running the Mirage on the surface like that because from what I remember, they aren't considered a surfacing prop. My main questions are:

1. Is it OK to keep running the Mirage + like this?

2. Is there any other props out there that would do the bow lifting like I need and be OK to run at or near the surface like I appear to be doing?

3. Would I be better off running a drive spacer to get the Mirage+ down farther into the water?



My original plan here was to call somebody like BBlades, but honestly, I don't have thousands of dollars to spend buying and selling a bunch of props just to try. So any help here is greatly appreciated!!!

I should also add that this is a stock Bravo One drive with a 1.5:1 gear ratio.

Nice build, i am interested in seeing your results.

I don't think you can hurt the prop, it just wont hook up and you will have high slip. How high did you trim and what speed was 4500?

I think you will be happier with a cupped bravo 1, It will handle and hookup alot better and still give decent bow lift. For now run the Mirages @ WOT and report back speed, rpm, and handling, boat should run mid to high 70's if you can get the rpm. Might get some chine walk with the mirages

I know I just started to trim it when it started to rooster. As far as speed goes, I was right at 60. I don't know the exact number because I was watching all the other gauges with the motor still being new and I have already turned the batteries off which erased the recall number out of the GPS speedo.

I went ahead and called Brent from BBlades, and man, that guy was a huge help. He thinks I need to stick with a Bravo 1 as well. He's thinking a 24 or 26. So I am going to borrow a buddy's 24 this weekend and give it a whirl. We went over my dyno sheet and figured we need to shoot for 6000-6100 rpms. He said I need to find an unworked prop that will get me to 5700-5800 and his lab work will get me the other 300 rpm as well as provide me with more bow lift. Also, he said the rooster tail doesn't concern him at all as long as it isn't slowing me down. So I have a good starting point now.