mikesufka

Guys -

I'm running a 30 Spectre with twin 300 Merc Promax's (not 300X's) and 15 X 32 Merc Lab Cleavers. Best speed so far is 98 MPH. This has occurred one time, on glass calm water, if you can believe that. Most days in almost any conditions, the boat runs 96 MPH @ 6100 RPM's. With regards to engine height, should I try an adjustment? Up or down and how much? I know that if I overtrim now, the boat will start to seek left or right.

Any ideas?

Thanks,

Mike Sufka
St. Cloud, MN

VEGAS36CAT

what's the weather like now? That is strong if its hot up there...Two of our friends have 30's (one is my old boat) the ProMax boat is running low 90's right now in Havasu heat (110 degrees) and the 300X boat runs upper 90's. Will touch 100 with one person on board. Slowed down 5 MPH or maybe a little more from the spring time. What are you showing for water pressure at speed? Honestly your numbers are right in the ballpark...

dkwestern

Have you tried smaller props? The 300's should rev to 6400 or so I believe, that might get that cat moving along better, but ????

dirtlawyer

I would think you should be running a little faster than that - the 32's are probably the right prop - I would check the motor height. What water pressure are you seeing? My motors are set up so that the prop shaft is about 1.5" about the bottom of the boat - seems to be the sweet spot.

berns29scarab

i had a 98 30 spectre with 300x's..2 people 1/2 - 3/4 full of fuel slight chop she ran 107 on a GPS...was a consistent 102-103...in at the jersey shore so there is a lil difference in altitudes im sure, plus temps and humidity play a big part as well. i spoke with Jay at Spectre about my boat a few times and i dont recall the figures exactly but my set-up was conservative (engine height). he said i coulda have raised my engines another 1/4" and still been on the safe side. i was spinning 15x32 labbed 3 blades. the dealer i bought my boat from said with the engine heights cranked up they saw 112 out of my boat before i bought it.

VEGAS36CAT

he has the promax's--not the X's...6200 is the number on the promax