[nglauer]

MODERATORS PLEASE FEEL FREE TO MOVE POST.

I wanted to get everyones opinion on pitch and smart tab adjustment.

My boat is a 2001 Mariah Diablo 180, with the 3.0L motor.

I recently installed Smart Tabs and am running a 17p prop... which I had installed prior to the tabs, to help get the boat on plane faster. I have a 19p that ate a stick last season, and I'm getting ready to have it rebuilt. My question is this...


Should I have the 19 fixed, or re-pitched to something else?

My goal is to run at a lower rpm, while achieving a higher speed. I believe the smart tabs have eliminated the need for a 17p.


The 17p with Smart Tabs SX runs in the mid to high 30's roughly 35 mph, per the GPS on my android phone. It averages 4500-4800rpm depending on the number of people/water conditions. I try to keep it below 4500rpm.

What RPM is the 3.0L capable of?... running above 4500 just seems high
What prop will give me a lower RPM with a higher speed? or do I need the higher RPM?

We don't pull anyone behind the boat yet, but I'm assuming the 17p would be the best candidate when we do.

Also, any suggestions from those running the smart tabs SX. I'm still set on the 3rd hole. Anyone running a different adjustment with better performance?


Thanks for all the help.


Nick

[180diablo]

I assume you have already checked out the smart tabs thread on here? If not, you may find your answer in there. I don't think I have read through the whole thread..heh.

Smart Tabs

The best my '93 3.0L will do is about the same as what you clocked it out on your GPS (I clocked mine also a few years ago). I think I ran it around 4200rpm and found anything higher "rough" sounding. I also don't have Smart Tabs installed.

If you want to crack the 40+ mph range, swap it out for a 4.3L. Otherwise, you are probably running at the top-end of it's capabilities.

Prop talk: Wait for MikeyT to chime in. From what I remember, he is the prop guru.

[nglauer]

I haven't messed with the smart tab adjustments yet.. I know the #3 hole is the one they suggest to start with. I'm not sure if I would gain anything by setting them +/- a hole or so. Just curious from those that have. I will jump to the Smart Tabs thread and see if anyone has an opinion.

I don't think i'll ever get my boat above 40 with my wife and kids in it. Although.. I did take my cousin out when we first got the boat.. on it's maiden voyage and swear that I was running 42-43 mph. This was trimmed up slightly on smooth water, and no wind, and light on fuel (under 1/2 tank). I also had the 19p prop on at the time.... but perhaps my memory is wrong.

Thanks again!

Nick

p.s. how hard would it be to swap to a 4.3? has anyone on here done it?