bob

Weiland77, how are you measuring speed, gps or speedo? Tidal water?

wwwTOPDJcom

I say try a 24 bravo, Im running a 26 on a 25ft 4500lb boat with a 502 efi
I tried a 27 mirage unlabbed and the speed was good but it blew out too much the labbed 26 bravo gets me 70.8

Whiteknuckle

I don't get it! The boat does not know if the engine is running good or not. The end result is he is only going 58MPH with a 25P prop at 4800. That is not good. The prop is not doing a good job, or there is some other reason why the whole package is so ineffecient. I agree the carb is too big and he would get better throttle response with a 750-800 CFM, but I don't think that is the issue.

wieland77

iTrader: (1)

I was measuring speed with a GPS. I was also having a little trouble with my port tab and could have been producing too much drag. I also had a problem when I first got engine going with it fludding and I am going to replace the plugs incase one was fouled out and not running on all 8. After I do that and I got my tab right I will put it back in and check speed with RPM range and I might solve problem with new plugs and correct trimming. Thanks again for all the infor and options, I will also look into getting a 800-850 carb. More Power just put this new 950 carb on, do you know what they choose a 950 instead of a 800 or 850cfm? I assumed they put that one on to best match the engine. THANKS AGAIN...

onesickpantera

iTrader: (1)

I would think to get those slip numbers you would have to over trim to get those rpms, which would mean you're down on power. That is where I would start.