Adding lift

[Guest]

We are fine tuning the D/E MOD hydro and after watching a few videos we decided to add a bit more tail lift by adding a 3 mm shim in the tunnel. We will see if it is faster at the NBRA nationals.

Alan

[ZUL8TR]

shim and lift?

Alan

Please explain the shim leading edge design and its expected affect on lift. Is this something you saw on other hulls?

[Guest]

Tunnel

I will take some photos later today when I take the weight off the boat.

Alan

[Guest]

Bottom Work

I have included a photo of the old white boat which has a pad in the center of the tunnel that helps increase the air pressure developed at the aft riding surface. The new boat is 1" wider and has a larger tunnel so we decided to restrict the airflow going through the tunnel by making it 3 mm less in depth.

The plywood is beveled at about 20 to 1 at the leading edge so there is minimum disturbance going into the tunnel. It was glued with west system in yesterday and today I blended the leading edge to the bottom and put the first coat of west on the plywood. Hopefully we will see some increase in speed.

Alan

Note: Notice the spray off the aft chine on the two boats.

[ZUL8TR]

lift

Very interesting. Post results and a photo of the hull underway to see the new riding condition.

[Guest]

Bottom work

The boat responded very well to the bottom work we added to the tunnel. Speed was up and we saw in excess of 83 mph on the MyChron data system with the D MOD Merc. We had a mishap with the best engine and had to go to a new never run backup power head. After getting some time on it we started to see fairly good performance but it still tight and was down 400 rpm from the other. It ran good enough though for a second out of 14 boats entered in the NBRA long course nationals.

Alan
Aeroliner Racing

[ZUL8TR]

test data

cool running, looks cleaner