What ratio is your drive? To hit 84 mph at 5400 with a 1.50 drive and a 26 labbed (equal to a "true"24 pitch prop) your slip would be less than 0, even if your labbed 26 is truly a 26 pitch your slip would have to be at 5% which is not going to happen with any Baja in the size range of yours and mine , 15-20% is more common , my similar boat runs 74-76 mph with a labbed 26 at 5500 (when I take my blower belt off) , Smitty
I attached a link for a prop calculator for you, verify your drive ratio and play with the numbers, use 15%-20% slip for your calculations and you will be about dead on
http://www.rbbi.com/folders/prop/propcalc.htm

I forgot to mention, if I ease up to high speeds it's fie, oil pressure stays at 35-40, why would that be?

I am not sure on the ratio, I know there Are thicker gears and a steel tower other than that I'm not sure, I will find out. I hit 78 on my phones gps and still had throttle left, but my boost was getting up there, I never hit the rev limit, I had to shut it done, started to walk on me. I just want to set it up to go fast, won't live at high speeds, just visit sometimes, most important no problems.

It will be important to know what ratio your drive is when you start thinking about buying props , I would think it would have 1.50 gears, with the 1.36 a 28 pitch would be like trying to turn a 32 and thats not going to happen real well with 700 hp, good luck and keep us posted, always love to hear about other fast Baja's, Smitty

You got it, thanks for all your feed back, I truly appreciate it!

Disconnect the downstream hose from each of your coolers (oil on the front, power steering on the back of the motor) by loosening the hose clamps and sliding the hose off. Sometimes they are had to get off, I used a very small flathead screwdriver working parallel to the hose to loosen it. Don't pry up or you will tear the hose. Then take the big hose loose on the front of the motor. Blow water backwards thru the cooler and engine. Most likely you have some passages of the oil cooler blocked, causes engine to run hot and oil pressure to be lower. With the amount of money you already have invested would recommend another 400 or so for a sea strainer. Living in Florida I became rather proficient at backflushing silt and sand from my 25OL. BTW I was running around 575 hp with a labbed 26 Bravo (up to 27) 1.5:1 outdrive at 76mph at 5600 rpm. I would think with your power you will need a 30p Bravo.

I found that ratoi info.... 1.5:1 27/32 hylical gear set....

Thanks a ton, I'm learning as I go here, not sure which hoses are which, and when you say blow backwards thru the cooler is confusing me ( sorry ) do you mean put the hose directly to the inner cooler ? Is there any vids I can look at to help that you know of? Visual helps me to get a better idea.

Well the impeller is out, looked find, housing not so good, changing both. I think the water temp is getting up there due to lack of water. I cleared a line and there was a little plug looking thing in it, I removed it and the water shot out of the pisser. I think it was used to regulate the flow. There is only one pick up for both inner cooler and motor, there is a tee in the line. Going to do a separate pick up for both, but going to try a reducer first, Also show only 10psi on my mechanical water guage mounted on the motor, should show 30psi, could the crappy housing cause this?, back flushing the crap out of t. Another thing, my boat had to get it's first tow, shut motor off, them couldn't get it to restart, can't hear my fuel pump, is there a fuse or relay ( aeromotive 1000 )

I forgot, my oil pressure drops when I get on it pretty good drops to about 10psi, if I stay in it it starts to come back up then when I get out of it it instantly goes back to 40psi I have a windege tray and the oil pick up is welded on the oil pump, at cruising speed its fine. Im putting a mechanical gauge on it but wondering if anyone can help. I was told to put a bigger oil cooler on it but not sure what that would do. Again, any help is great !