What prop sizes are you guys running that have a straight hull 34 Vyper with 500 HP's ? I am running 24 Pitch 4 blade mirage props turning out and at 5100 RPM. What props and speeds are any of you getting ? Just was wondering if i should go to a 26 Pitch instead. Boat pulls hard from start to finish just feels like shes got more to give on the top end.

Mirage props are 3 blades. Are you running Bravo I 4 blades?

I don't have any experience with the non steped hul but I had a 1999 Viper wuth the steps and HP500's. All the hulls like mine came with either 30' or 28' bravo 1's. Speeds with that combo weere arounf the mid 70's some got 80.
Based on your rpm's I think you have it right, you may be able to try one size larger but that may be too much without the steps.
The attached pic may give you some idea as to what the drive height was on my 1999. If yours in much lower you may be better off with a 3 blade in the 26 to 28 range.
Good luck

You are correct i mis spoke i have the bravo 1 4 blades. I am sending them out to BBlades to have them reset to make sure they are in good shape and will go from there. I was just looking to se the 80 MPH zone, looks like I am not far from there but that last few MPH seems tough.

so what speed are you getting with the existing set up

Boat will run 78 GPS in a good chop but a bit slower in smooth water, I am planning on doing a top end upgrade with Bob at RM but probably not till next year, so in the meen time i thought i would play with the current set-up to see if i can see 80 the way it is.

Try to crack your engine hatch open to let some more air into the engine comp. If you look at the newer 340's and 380's, PQ added these vents on the side of the gunnel after finding out the bigger engines were starving for air. When I first tried this, I rolled up a couple towels and stuck one in each corner between the rear seat backrest and the head rest and then closed the hatch on them. This left about 1" gap, wich is all it needed.

If you can get 78 with the straight bottom you are doing very well. As good as others with the steps. Congratulations, you have one of the better straight hulls.

I had a 96 Vyper 34' straight hull w/ 525sc's I was running 4 blade 28's. Top end was 78-81.

BL6 So how do you compare your Formula to the PQ Vyper ?