proping an 89 flat deck
 

The boat in an 89 TG with notch transom, is 575-600 hp enough power to spin 28 4 blades to 5000-5200 ?

kinda what I was thinking, It has 23's on it now and reving to 6k+, maybe a mirage 25 + 3 blade ? engines are 580's dart intakes and 1100 dom's

He's not sure no speedo working in the boat, Id guess 68-72 but just a guess, I'm just trying to get the rev's down and pick up a little speed

Thanks, I asked him to down load a gps speedo app on his phone and give me some numbers next time he's out............I'm thinking his boat is around 10K

A 38 Flatdeck will be around 11k dry. It will depend on the hp/torque curve of the engines as to how to prop it.
I would say to try going up 2-3 inches in pitch to start. I doubt he would be able spin the 28 Bravos to 5000rpm.

Top gun will weigh around 9800-10,000 with light to no fuel, what drives?

That HP with TRS?? your looking at worked 25 Mirage plus or 24 Hydromotives spinning 54-5600 range, or a 24-26 Bravo around 5200 speed should be 74-77 ish depending on actual HP it has and conditions.

If Konrad boat with 600 HP a 26 Bravo1 will spin 5200@ 73 mph or close to it. or a 28 to 5000rpm at 71mph

Its been awhile but i seem to remember my 525sc's, trs, 26p bravo @ about 4900rpm, 71 or 72 mph using gps phone app.

Thanks for the info guys, I asked him for mph #'s from 4k to 6k in 500rpm increments, it does have gps speedo but he wasn't watching it, it is a trs boat so I don't want to put to much stress on them, boats been sitting for 5 years, I fixed the engine problems a few weeks ago he's just glad to be back on the water.

Thanks man, I'll check with Mike..........are they in KC ?

With TRS and 575-600 HP personally I would stick with 3 blades if he beats it at all, leave that couple % of slip trust me... I bet a worked 25 mirage will perform great and help keep drives alive, that power level is about all them tiny lower gears will take and stay together, 4 blades or more then 600 HP create time bombs.

my 2 cents
i am spinning 4 blade 26 pitch hydromotive props
considering still getting use to these motors
547 about 700hp???
boat ran 82 at 5600, 4 people full tank of gas, and flat water

TIME BOMB?????
hmmm really i hope not,,,, well i know my boat has had same set up since early 90's
i know prior owner had one drive rebuilt, never said anything more.
but i have owned boat since 2012 ,,same props,,600 hp now 700 hp
i just try to run easy on drives and boat..keep it in the water...

plus 2,000lbs

I guess it's because I use mine like intended, I don't baby it, why have it? I bought a SSM boat after trying to keep TRS alive for years...