spectras only

You don't want to run the silent choice at high rpms. It's for the water popo,only when cruising at low speeds around marinas,lol

boating11

Yeah i know. The only time I do use it is when docking...

spectras only

32P five blade is too much IMO, 32 B1 four blade would probably get you where you want to be.

thirdchildhood

iTrader: (6)

Use the silent choice only at idle or very low speeds with the 525s. The Mercury manual says only below 2,500 RPM.

Next, get your RPMs up so that you bump the rev limiter running light. Near 5,400 RPM is where these engines shine. Also, get any extra weight out of the cabin. You are right; You should be running mid to upper 80s from what I've seen.

lol, three posts when up while I was typing this!

VoodooRob

Hopefully someone checks in with same boat/engines that can verify prop size. My 525s with 1.50 XRs run 5 blade Maximus 30 props. 32 seems like a lot to spin for the set up.

Esquire

Here's a link to several magazine articles on the 38ZR. All say the boat topped 90mph. The first article says it was running 32" 5 blade Herings at 91mph. http://www.donzimarine.com/Boats/ZR_38_Extras.html

Scagburner

Not sure about the compairson but my 36 Sunsation is running in the low 90's with 525's and 32" 5 blades. I don't have a ton of seat time yet so I'm still figuring the optimum trim settings but it's turning ~5200 - 5300 RPM.

Pwraddr

Markdonzi on here had a 38 ZR with 525 and had herings on it and I think it went 90. With maximus I think it ran upper 80s.

Send him a PM, I'm sure he would tell ya what he had.

Bullhead

I had an 05 38zr with 525s, XR sport masters, 32 pitch 6 blade herrings.....it had rear bolsters which added weight over a standard bench back seat.....it was always good for high 80's and routinely ran in low 90's......I do not think it required much trim for this hull to find it's sweet spot.....Also I would be careful over trimming as this will create a condition to break prop shafts

ballz2thewall

First check your fuel/water sep filters if theres no water or ethanol separation then You need to have both engines compression tested, spark tested, leak down tested, and checked out on the diagnostic laptop by a reputable high performance shop and then take it from there