z280 props
 

any body know what were on these? i got bravo III with i think 26 p. it plains for crap only turns 4000 rpms. any sugestions. thanks tom:wink_thumbup:

Re: z280 props
 

Dropping down to 24" props will increase your WOT rpms approx 400-500 and should help with the planing problem. You might want to be sure what props are on the boat now though before you go & purchase a new set.

Re: z280 props
 

they were 24. my wife hit something and took them out. these are a buddys and were laying around. i thought they might get me some more mph but i got less. 24 didnt come out that great either. bow down trim down still didnt like getting on plain (454 efi)

Re: z280 props
 

The 24's were likely what was original with the boat and dropping all the way to 22" will bring up your WOT rpms to about 4800-4900 which is way above the recommended 4200-4600 range for a 7.4mpi, if you are at 4000 with the 26" props. With a boat your size & weight it's critical that you get the props right for the best performance. You should be up around 45-47 mph at WOT with that 7.4. If you have a 454MAG though you have some room for the 4" prop drop as the recommended rpm range is 4600-5000. Going down to a 22" set though will likely leave you a little short of 45mph but it should literally pop out of the water. Does your boat have trim tabs?

Re: z280 props
 

I would say 24's would still be the right ones. Do you have trim tabs on the boat? If not then get them. Aint no way this boat is going to hit 50mph though. Also keep in mind the health of your engine. Its only natural for performance to drop off over the years from when new.

Re: z280 props
 

its got 7.4 mpi yes trim tabs. the best ive got the boat was 39.8 on gps with the 24p tach didnt work then. i was hoping for 45 mph. the 26p is 36mph under 4000 rpms. trim tabs down trim down, slugish. trim up a little,tabs up a little, then trim up a little again and it goes. then tabs to adjust ride!

Re: z280 props
 

Short of building in more horsepower I dont see any way of getting it up to that speed. I was guessing you were probably around 40-42 mph. If 24p and trim tabs isnt getting you out of the hole like you want you may be forced to go 22p. The problem is your speed is really going to suffer. Its always a tradeoff so if you really want more speed you may hate it. As much as I love speed I like to be able to instantly feel it when I push the throttle. I think if you buy new they offer a 23p with a higher cup which may help.

Re: z280 props
 

I called Arizona Speed and Marine last week about re-flashing my ECM to get more power.

ECM/ECU Tuning

On my standard 7.4 they claim 14-20 more HP and will add 400 more rpms. They can get rid of the low end bog (over rich condition) & gain fuel economy.

Its' like $400. Best dollar per HP gain you can buy.