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-   -   311 Props Questions (https://www.offshoreonly.com/forums/formula/259863-311-props-questions.html)

jiffy292 08-21-2011 03:36 PM

ran the 25 mirages yesterday ran good turned them 4800 but having an issue with one motor only turned 4500. the cruise is good, 3500 at about 46 mph. they seem very similar to 24 4 blade rpm wise

TylerBurich 08-23-2011 05:23 PM


Originally Posted by Audiofn (Post 3484449)
The only down side to the TRS with these baots is the lack of room up front when doing a water pump (the nasty azz job I am about to start this AM). Other then that from what I have seen the TRS boats perform better then the bravo ones.

I believe in 88 when they were Offshore Powerboat of the Year it was the 420 trs boats. Better balance and handling with the trannies pushing the motors further forward. I was actually referring to Konrads or something like that. Too much $$$$ for me right now.

endeavour32 10-11-2011 10:12 PM


Originally Posted by jiffy292 (Post 3484712)
ran the 25 mirages yesterday ran good turned them 4800 but having an issue with one motor only turned 4500. the cruise is good, 3500 at about 46 mph. they seem very similar to 24 4 blade rpm wise

Were you able to run the mirage props with the engine running right? I'm wondering if its worth it for me to try Mirages on my boat. I'm more interested in feel, bow lift, handling in waves compared to the Hydro's.

s022mag 10-11-2011 11:01 PM

I ran my 88' 311 with 425 hp TRS drives 25p mirage plus this pass Sunday and for some reason I only got 4000 rpms. Not sure on speed either, didn't have gps on, and my trim was up around 5.

I'm not sure why I only turned 4k especially w/ 425hp. I'm going to verify I have 425's when I can find the serial number on the blocks seeing I just bought the boat, if not then I'm suing my surveyor. If they do then I'm going to try 23's this weekend.

endeavour32 10-11-2011 11:48 PM


Originally Posted by s022mag (Post 3525272)
I ran my 88' 311 with 425 hp TRS drives 25p mirage plus this pass Sunday and for some reason I only got 4000 rpms. Not sure on speed either, didn't have gps on, and my trim was up around 5.

I'm not sure why I only turned 4k especially w/ 425hp. I'm going to verify I have 425's when I can find the serial number on the blocks seeing I just bought the boat, if not then I'm suing my surveyor. If they do then I'm going to try 23's this weekend.

What carbs does your engine have? I believe the 425's should have holley carbs. The mags would have Quadrajets. As to your props going from 25's to 23's isn't going to change much. My guess is that you have something wrong with your engines. Did you check the compression? Another possibility are your tach reading correctly?

Just an FYI, my 292 with 330's will turn my Hydromotive Q IV 24 pitch props 4600 RPM's. 292's and 311 are almost identical in performance with equal power.

jiffy292 10-12-2011 07:00 AM

Endeavor, I Lost That Motor Spun A Main. I Am On The Verge Of Parting The Boat Out Again Cant Make Decision. I Have All Kinds Of Parts You Might Like....large Rect Port Heads 25p Mirage Props... Let Me Know Should Know In A Few Days What Im Doing

s022mag 10-12-2011 12:25 PM

Not sure if the tachs are reading right, wouldn't know how to tell anyway. I do have Holley carbs, the chances of both motors having same issues at the same time?? I haven't checked compression either.

aggressive behav 10-12-2011 01:05 PM

I'm glad to see people are still boasting about their 311's. I just got a '88 with 2-525hp magnums. seems to have been a great boat in its day and still holds up!

pgolder 10-12-2011 06:10 PM

what props are you running? I run a similar set up with trs's.

s022mag 10-14-2011 07:27 PM


Originally Posted by pgolder (Post 3525856)
what props are you running? I run a similar set up with trs's.

Im running mirage plus 25p. The guy I bought the boat off of said that the original set of props that he had he let a friend borrow them and they were stollen when he's buddies outdrives were stolen. When his buddy got his insurance claim he bought him the current props I have which arenthe 25 mirage plus. Do I think they are the same props he originally had, no. But that's what he claims. He did mention when we water tested it that the newer props performed different, whatever that meant. He also said the boat ran 70.


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