where should i prop based on dyno #'s and cam??
 

dyno
trq hp
3500 645 425
3750 642 454
4000 643 486
4250 655 527
4500 647 552
4750 642 579
5000 624 593
5250 609 609
5500 603 631
5750 583 639

460ci, full roller, weiand 177 @ 6.5 lbs
-Comp cam int 613 / ex 613
dura 234 / 240
lobe sep 112

Where should i try and prop?? Its a 96' non-stepped 38' scarab.

Re: where should i prop based on dyno #'s and cam??
 

ill be in the unsensored section waiting for a reply....

Re: where should i prop based on dyno #'s and cam??
 

i would try for about 5500-5600

Re: where should i prop based on dyno #'s and cam??
 

Prop for 5250. Have a good hole shot and keep those motors turn key.

Re: where should i prop based on dyno #'s and cam??
 

try and prop where the trq equals the HP @ 5250? or does hp take over as trq drops?

Re: where should i prop based on dyno #'s and cam??
 

I'm with vette, try for 55-5600 to start.

Re: where should i prop based on dyno #'s and cam??
 

a good rule of thumb is 1200 min. above torque peak.

Re: where should i prop based on dyno #'s and cam??
 

It looks like you didnt find peek on HP . But 5750 should be close . it was tappering off there.It was carrying your TQ #'s pretty good up to 5750 so it should pull up to 5750 real good .

Re: where should i prop based on dyno #'s and cam??
 

Good advice, IF cammed for 5250.

I'd try 5700-5800, for this setup, to start. A little higher than I would personaly want, but you have to prop for your combo.

You must prop according to power curves, hp ;and tq, propping at highest hosepower and making sure tq peak 1200-1300 below that.

Getting a dyno break-in 'proves' reliability of new engine(saving possible nightmare of finding early engine problem after it's in the boat), and provides important imformation to optimum tuning. Tuning for best power curve data, then using to select prop pitch.

Running WOT at too low of RPM's is not utilizing the motor to it's efficiency; 'torque-loading' outdrive is bad for it's longevity and results in lower overall performance.

Re: where should i prop based on dyno #'s and cam??
 

thanks for the info... ran boat today, motors ran great put could not spin 28" NON-labbed Bravo's past 5,000. (full load fuel and humid). Thinking of buying 28" labbed that should give min of 200 r's according to Throttle up. If still need more i will try and get them turned to 27".

Is it correct to assume that the extra r's from going down in pitch will give me more power because of faster blower speed which will help me turn into the higher r's??