I think the main question here is can you spin out in the reeds ?
I recently had my drive rebuilt and since then I can only get 84-85mph on the rev limiter @ 5600-5700rpm. I do not what gears were in it before I had it rebuilt. Any thoughts? I think a different ratio was used like 1.5s and I probably had 1.36's:idea: Don't know. I am currently running a labbed 30 that would not see the rev limiter and the boat would run 104 on a good day and hit a hundred consistantly anytime else.
I think the main question here is can you spin out in the reeds ?
Maybe if I take some lessons
What RPM's were you seeing before your had it rebuilt?
What RPM's were you seeing before your had it rebuilt?
Around 5400-5500 in the heat
It seems to me if your seeing more RPM and less speed and nothing else has changed outside of the drive....Ex: same prop.
Then the gearing in the drive has changed. So I agree with you that it appears possible the wrong gears were installed during the rebuild process. Both those ratios are very popular.
Is this speed GPS verified?
or you have a crack in your prop and are spinning higher rpms, but getting less mph. check it first
Brian, try this link and play with your numbers - according to what I put in -
1.36 @ 30 pitch, 5500, 10% slip has you at 104
1.51 @ 30 pitch, 5700, 10% slip has you at 96
Seems you're still 10mph off?
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On a happier note, the wetbacks who bought Pete's house have it up for sale (fire sale, that is).
http://www.go-fast.com/Prop_Slip_Calculator.htm
Sounds to me like you might be thinking right. Call up whoever di your build and talk to them. Find out what gears they put in it and if they have your old ones.
A 200 rpm drop will not cost you 20 mph though. There is something else wrong here.