V-6 Viper set up issues!! Looking for advice

[Hydrophobic guy]

Have a Viper with a 175 Merc standard lower with the two top water holes plugged off has a Bobs 5" plate motors even with the pad 12 gallon tank in rear with battery 28" small ear chopper hydraulic steering solid mounts. Took her out in relatively calm water. Boat porpoises at low speed I guess typical from what I've heard. Got it up to a bit over 80 a few times with me and passenger and it was stable for a bit then started some pretty nasty chine walking also the motor was getting hot close to 200f. Control was much worse when it was low on fuel. Anybody have any advice on the temp problem or setup advice aside from me needing a lot more seat time real help from V-6 Viper owners would be appreciated.
Thanks all.
Josh
<!-- / message --><!-- sig -->

[terry taylor]

HI. Plugging intake holes, sounds like your ready for a lower water p.u. nose cone.I might add if filler or what ever squished into channel it will reduce water flow from remaining inlets. As for handling balance ever thing in and on the boat move any and all weight rearward thanks.

[Hydrophobic guy]

Thanks for the reply which Peterborough?
The holes are filled with aluminum tigged. I just pulled the lower to check out the usual culprits but nothing anywhere. With the motor at that height it may be losing pressure if thats it lower is next. I'll have it out this weekend and see what the girlfriend says the guage is at. She's just getting over the past outing and can probably focus on something other than the inside of her eyelids. Going from the fastest thing she had been in, a canoe to a Viper ride I can't blame her. And yes it definately seems they like the weight in the rear. Just a bit tough when your in transition from the stone skipping feeling to getting on pad. Boat is a blast thou. I'm sure with patience and seat time it'll get there. I spent a month on the bottom Kevlar and epoxy work YUCK!! so this is the final stuff to deal with. Thanks again for the input.

[Capt.Insane-o]

Your going to need a nose cone most certainly. Get a 26 big ear chopper or amazco re 26 and set the propshaft even with the pad to start. Go through the cooling system starting with the water pump.Your cooling problem may be that you are already sucking air and a water pressure gauge is a definate must have. LOTS of seat time helps

[Hydrophobic guy]

I have a 26 big ear figured it would like the 28 small better. I'll give it a try what kind of rpm's should it spin with the 26? And the 28 was set even with the pad. I do have the psi guage will take some accurate readings and go from there. Figured it most likely would need a pick up but have kept the budget low on the puppy. Just ran it 10 mins ago after going thru the cooling system found no problems with pump or popit etc or crap in the lines. Thanks for the input

[Capt.Insane-o]

Which 175? 2.0 liter, 2.4....2.5? A basically stock 175 should spin a 26 7000-7200 on a viper.

[pengilly]

If you cant drive it a couple of small trim tabs mounted on the back of the boat about as far away from the pad as you can get will be your training wheels. mount them so they only get spray, it helps alot. Good luck......youll need it:)

[Hydrophobic guy]

Motors a 2.4 will see what happens this weekend and try the prop switch etc and mess with the height and see what we get for pressure issues. I figured it would need a nose cone pick up. Boat is rock solid After the usual gut out and redo crap used kevlar for reinforcing the bottom. It
was pounded in a 2.5' chop for 2 hours its first time out boat was fine but I lost some fillings. Nice to have a friend who builds very high end power and blow boats for donations to the cause. Has anybody used tabs effectively on these boats? The way the rear is angled can't see it working well. Gets up and on plane fine but anybody been running a tail? Will see if I can get some in flight pics too this weekend.
Thanks all.

[Capt.Insane-o]

I would'nt put any sort of tab of any kind on the boat, learn to drive it naturally. They are'nt a rough water ride either.

[Hydrophobic guy]

Yup, running it in that crap was more punishing to the crew than the boat. Will see how things go this weekend. I respect what this boat could do if poked with a sharp stick. Don't wanna go swimming just yet way to cold up here. Will post results.
Thanks for the input Capt.

[Hydrophobic guy]

Put the 26 big ear on found better out of the hole but more unstable than the 28 little ear probably neede to bring the motor up more but with the water pressure issues figured it was a bad idea. Unless trimmed almost even or lower motor gets hot quik best pressure was 10 psi and bounces around. Trim it up and forget it even dropped the motor a bit no change except handled worse. Definately needs a LWPU, on order now. Tried weight all over the place and found still likes weight in rear with more in port corner. Porpoise is what it is kinda sneek up to getting on pad. Chine walk isn't to bad just react lightly when it comes up and it keeps it calmer. All in all pretty happy with it. We got poured on at one point but you dry out quik with the wind blast. Will post pics next week rained out this one.

[pengilly]

1982 Hydrostream V-King F/S

Thats where we put the tabs, they helped alot for driving the boat and they just run off the spray.

[Hydrophobic guy]

Which 175? 2.0 liter, 2.4....2.5? A basically stock 175 should spin a 26 7000-7200 on a viper.

Good numbers thats exactly what it was spinning yesterday.