Is there a rule of thumb for PVS plugs?

[ch]

I’m wondering where to start (whether to go bigger plugs or smaller). My hole shot is great. But as soon as it starts to plane out I can hear and feel the prop break loose. Then I have to feather the throttle a bit before I can get a good bite and go. So ya think I should try the bigger holed plugs or smaller holed plugs, or even the solid plugs first. If it matters, it’s a 250 Merc 2 stroke on 20’ triton trx.

[born 2 fish]

Smaller you can experiment plug one leave two open I went from large to completely plugged because of the exact issue your having. But I have a 4- stroke.

[xb03fs]

Is it surging or does it grab and go? If it dosent surge no reason to plug

[jarhead175]

I struggled to get my boat adjusted. So what I did was bought soild plugs and used a cordless drill to drill out the holes.

[21XDC]

No rule of thumb... Target 3800 rpms on holeshot. That is a good starting point. Motor height also plays into this.

[xb03fs]

Interesting on my boat 5000 less or more with promax is quickest

[21XDC]

Interesting on my boat 5000 less or more with promax is quickest

I have props that like 5000 rpms on holeshot... But 3800 is a good starting point for most average bassboats.

[Chainslinger1959]

Smaller you can experiment plug one leave two open I went from large to completely plugged because of the exact issue your having. But I have a 4- stroke.

4 strokes do not require pvs plugs I use solid on my merc 4stroke.

[mactlman]

4 strokes do not require pvs plugs I use solid on my merc 4stroke.

i have heard of boats with the new 4s merc needing venting?

[mactlman]

I’m wondering where to start (whether to go bigger plugs or smaller). My hole shot is great. But as soon as it starts to plane out I can hear and feel the prop break loose. Then I have to feather the throttle a bit before I can get a good bite and go. So ya think I should try the bigger holed plugs or smaller holed plugs, or even the solid plugs first. If it matters, it’s a 250 Merc 2 stroke on 20’ triton trx.

fury prop? seems to be common to almost break loose at roll over??

[buster502]

sounds like you need to add one large plug in and two open holes,thats what i had to do with mine it would blow out right when it nosed over and rpm went to high for me and had to feather it,i added one large plug and 2 open holes perfect now,not a fan of blow out and feathering,mine is a tempest plus 25p

[Chainslinger1959]

4 strokes don’t need ventilation like a 2 stroke . Sounds like too much ventilation to me pvs plugs are cheap buy several and try out.

[JoshKeller]

sounds like you need to add one large plug in and two open holes,thats what i had to do with mine it would blow out right when it nosed over and rpm went to high for me and had to feather it,i added one large plug and 2 open holes perfect now,not a fan of blow out and feathering,mine is a tempest plus 25p

Same with my 25 tempest

[bass.man65]

I’m wondering where to start (whether to go bigger plugs or smaller). My hole shot is great. But as soon as it starts to plane out I can hear and feel the prop break loose. Then I have to feather the throttle a bit before I can get a good bite and go. So ya think I should try the bigger holed plugs or smaller holed plugs, or even the solid plugs first. If it matters, it’s a 250 Merc 2 stroke on 20’ triton trx.

It would help to know what prop you have and what plug configuration you have now.

[ch]

Fury prop. My boat came with 2 sizes of plugs and solid plugs. I’m running the in middle size that came with the boat. Before I raised my motor an 1 1/4” it came out of the hole real nice. It was way too low I thought at 4 1/2” below pad. Now that I raised it, the chinewalk ain’t near as bad, but on take off, as soon as the boat breaks over, the rpms spin up fast and the boat seems to slow it’s acceleration till it bites.

[Whitaker201]

Fury prop. My boat came with 2 sizes of plugs and solid plugs. I’m running the in middle size that came with the boat. Before I raised my motor an 1 1/4” it came out of the hole real nice. It was way too low I thought at 4 1/2” below pad. Now that I raised it, the chinewalk ain’t near as bad, but on take off, as soon as the boat breaks over, the rpms spin up fast and the boat seems to slow it’s acceleration till it bites.

Drop one size in one hole and test again.

[billspence]

Understand what is happening. Exhaust is being run through the PVS holes over the blades of the prop. Too much exhaust over the blades, less resistance to the blades, and the blowout happens. Too little exhaust, too much resistance and the motor bogs down. Make small changes until you find what works for you. Remember that hot and humid weather will effect the motor and make the motor bog down easier, so don't get too crazy with it if it is overly hot and humid.

I will admit that I don't 100% know if the 4 stroke sends exhaust out the lower unit and over the prop blades, but I would bet it does. If it does, it doesn't matter if it is a four or two stroke. Maybe the low-end torque of the four stroke can overcome even no exhaust going over the prop?

The Fury prop is allegedly set up so that you won't need PVS. I never used PVS on any of the Fury props I had but I did use my hydraulic jackplate to improve holeshot.

A lot of holeshot is boat and motor performance specific. Weight in the wrong part of the boat can make it funky. Hot and humid weather hurts performance, even with an ECM sort of compensating.

PVS allows you to tweak your setup so you can be in the best position overall with respect to holeshot. Has no effect on anything but holeshot. You can't get there until you play with the amount of exhaust you have going over the blades of your prop. There is no way to tell you exactly what you need for plugs. Understanding what is going on and ensuring the motor is performing well will let you start dialing the holeshot in for you and your boat.

[21XDC]

This may help some understand...

[Grumpy/LGF]

This may help some understand...

Thanks for the video Mark

[ch]

Thanks fellas. I was planning on testing in small increments. I just wasn’t sure whether to start with a bigger vent hole or go smaller. I’ll start the testing. And thanks again y’all.