With a 1.1 ratio, you're spinning the props faster than you would with a 1.5. Normally, in combination with a lower pitch prop,that woud cause less prop slip. That leads me to think that different props would be better. A larger diameter might do it. Or try lowering the drives with spacers. Your present setup may have been good for very high speed that you are now unable to hit with your 525 hp engines. You have to find a set up that works for the way your boat is now.

I have a 525sc and just did the full MSD rig and 7.5 pulley. I got about 30 hp, i would say. That motor does NOT like more than about 5200-5250 rpm. Anything more than that, and you are just wasting gas. And with the 1050 on there, its a LOT of gas. I believe the cam, pulley, ignition, and exhaust will max these motors out. That number is around 575 or 580, i would think. In fact, the factory rev limiter is at 5400, so you CANT get over that.

Also, the chiller is a double edge sword, because it's restrictive it will actually REDUCE boost (teague said so), so that's why it comes with the pulley--to raise it back up to 5.5. So, I don't think the chiller is worth cuttin holes in the deck. Just take out the thermostat (again, teague says so), do the MSD, and run 92 with a tube of octane boost...It will be plenty ballsy with no knocking, mine runs great.

If you do order the pulley, BE SURE to get the 1/2 inch offset- and It's 100 bucks from Teague. It's worth it, even just for the sound..One thing- with the smaller pulley, you have to re-prop up about 1 inch or so, to slow the blower down, cuz it sounds like it's gonna go supersonic.. lol

Personally, I think you need to go to some 5 blades?