What I have is a 99 lightning single step that i bought a couple of years ago. It has has hp500 with small blowers Imco neutral extension boxes with shortys, Also has Arneson rocker plates. My problem is it starts to porpoises above 55-60 mph has anybody seen or done a setup like this?
Thanks

Just a suggestion, but try dropping the K-planes down a couple spaces?? From the sound of the set up, seems like previous owner just wanted topend. If you were to take the "Shorties" off an put regular lowers on should fix it, I am guessing, in mid ranges the bow is dropping allowing teh props to cavitate, thus resulting in porposing?

WILL

I agree

bob is it summer yet , we need to get the 35 out .

Are the extension boxes doing any good? I understand the shorties, but thought the boxes might cause the boat to to trim differently.

Will, one of issues is it doesnt have standard k planes it has Areson rocker tabs not exactly sure why, nor exactly sure how they are supossed help or hamper. Was told the previous owner wanted to run bow high in Lake Tahoe. But I cant get a hold him to ask why the set is the way it is.

Had a 99 w / 500s myself and never experienced this trait at any speed. Also have couple friends with single steps, one had a 97 with shorties and regular K-tabs, one a 99 with shorties and boxes and the longer K-tabs, both have big power and run above 100. Been in both and never did this either. Know someone that tried the rocker plates and didn't like the way they acted, switched back to the K-tabs. Don't remember exactly what it was he did not like about the Arnesons. The 35 pretty much runs on it's own, very little, if any, tab input required once on plane. Could be the hull does not like the hook / rocker induced by the Arnesons.

So it sounds like I should start by putting some k planes back on. Any suggestions on removing the silicone/glue that holds them on.

i've used piano wire pulling it back and forth until i worked it loose. I also have a 35' w/big power, rides like it's on a rail.

They are held on with 5200.. after removing the bolts put a wood block and floor jack under the tab and apply some pressure they will most times pop off if not the piano wire trick will work. (Tim)
not Summer yet how is your project coming along??