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-   -   True real speeds of 38 zr (https://www.offshoreonly.com/forums/donzi/338987-true-real-speeds-38-zr.html)

neva satisfied 07-07-2016 05:23 AM

You have to keep in mind that the ZR's love the trim.

Australia 07-07-2016 06:34 AM

not long. I did have about 9 people on it one day and needed some to get in the cabin to get it to plane. tabs down helps a lot

Backlash1 07-07-2016 08:23 AM


Originally Posted by Australia (Post 4456912)
not long. I did have about 9 people on it one day and needed some to get in the cabin to get it to plane. tabs down helps a lot

I am doing top end re-fresh this winter since I am at 250 hrs. Will prob do some port and polish work. Plan on doing an ecm re flash from whipple to up the power and rev limit at the same time. I will then go to the 32 herrings to get a little more top end. The extra power should help hole shot. The 38 zr prob should have 600s min in my opinion. Boat just needs a little more thrill. It would be nice to feel the boost.

Sydwayz 07-07-2016 09:11 AM


Originally Posted by Backlash1 (Post 4456940)
I am doing top end re-fresh this winter since I am at 250 hrs. Will prob do some port and polish work. Plan on doing an ecm re flash from whipple to up the power and rev limit at the same time. I will then go to the 32 herrings to get a little more top end. The extra power should help hole shot. The 38 zr prob should have 600s min in my opinion. Boat just needs a little more thrill. It would be nice to feel the boost.

Shoot a PM to "REMEDY" here on OSO. He's rebuilt quite a few 525s and has some proven tricks to get some great power improvements out of them. I'm sure he's willing to lend his advice.

Backlash1 07-07-2016 09:20 AM


Originally Posted by Sydwayz (Post 4456959)
Shoot a PM to "REMEDY" here on OSO. He's rebuilt quite a few 525s and has some proven tricks to get some great power improvements out of them. I'm sure he's willing to lend his advice.

Thanks I will

Captain YARRR 07-07-2016 09:42 AM


Originally Posted by neva satisfied (Post 4456902)
You have to keep in mind that the ZR's love the trim.

Very true.

Tom A. 07-07-2016 09:44 AM

From what I have seen in NJ, the guys are running 32 - 5 blades on the 525 boats and running high 80's.

I know Ron Potter is frequently rebuilding the 525's and making them 600hp.

My friend has a 700 38 that ran 110 stock and now runs close to 120 with the motors bumped up to 850ish.

Backlash1 07-07-2016 09:59 AM


Originally Posted by neva satisfied (Post 4456902)
You have to keep in mind that the ZR's love the trim.

I agree by 38 felt really good and loose when I trimmed to six on the indicator. Although I picked up speed and got off of the Revlimiter when I trimmed down to four on the indicator. But that was at wide open throttle. At mid range the boat definitely Feels really nice trimmed up at six and the roost drops down considerably due to bow lift.

370ss500efi 07-08-2016 08:47 PM


Originally Posted by Tom A. (Post 4456969)
From what I have seen in NJ, the guys are running 32 - 5 blades on the 525 boats and running high 80's.

I know Ron Potter is frequently rebuilding the 525's and making them 600hp.

My friend has a 700 38 that ran 110 stock and now runs close to 120 with the motors bumped up to 850ish.

Tom, what are you hitting in the zrc?

Tom A. 07-11-2016 01:56 PM

I have 700 hp Potter built 575's with Imco SCX drives spinning new 32-5 blade Herrings, I can get 105-107. I am going to have these props tweaked in the off season as I am losing a few mph with the diffuser ring at the end of the prop. It helps provide bow lift (which i don't need and scrubs speed).

The boat saw a best of 115 with a tweaked 5 blade Herring and the old Xr drives right after we bumped the motors up to 700. Those props took a while to get going and were not very good in the mid range, so we labbed them for better acceleration and lost a few top end mph. Then the Imco's took a couple of mph but have been great on reliability!


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