pullmytrigger

Agreed, try some 21 Mirages, I have same set up as you on my 29 Fever (non step, two sbc's, non counter rotating alphas), had 23 stainless Quicksilvers that the boat came with, couldnt get over 4200 rpm, currently am trying a set of 21 Mirages, much better holeshot, they carry the bow much better, can trim it out way higher (from 4 to now 6 on the mech indicaters)
old props, trimmed right out, spray would come out about halfway down the boat, with the Mirages the spray comes out about the last 1.5 to 2ft (thats more like it).... speed is the same, about 63 64 indicated (doesnt make sence, I need a GPS) I can hit 5000 with 4 people on board, low gas & flat water, I too would like to be about 4800, maybe some 23s are the answer.
Sutphil has a 26 or a 28 Sutphen, same set up, although his counter, he tried a set of 22 Bravo 1s and wants to keep them, maybe Ill see if my prop guy has a set I can try, I'll see if Phil will will chime in.
Get rid of those alum props........Ive owned several boats and played with props on all of them, a set of props can transform your boat............let us know your results......Doug

HOUSTONPROP

twinn29,if the Mirage props that you are trying are stock, You would benefit if you added a touch of cupping to the props this will allow you to trim higher and will pull the rpm down to where you need to be. A set of 23 's would be too much /Darin

Sonic30ss

I like this thread!
Huston prop, we tried to make connection earlier in the season, but I did not get a chance to call you.
Now that I have two fresh motors, I am better able to see how the boat reacts.( 87 Sonic 30 ss w/twin 5.7l 320hp efi motors with Alpha SS drives 2'' shorter than std Alpha.) Engine RPM should be 4800-5200. I can get about 4500 rpm @ WOT now, also getting on plane is a real chore tabs down, drives in
it takes about 30-40 seconds (cruisers pull away while I'm trying to keep the engines off the rev limiters!) I've tried other tab and drive settings but down/in is still the fastest. When underway, and not on plane, if I give a stab at the throttles the boat will move forward then the props will slip and go nowhere as the rpms increase. I can only get 8-10 mph before the props start slipping. I have stock 21p Mirages now. What do you think?
Thanks

pullmytrigger

Sonic- you might try a set of Bravo 1 props, they are semi surfacing and the extra blade will be much more tolerent of your high x demension, My old Donzi had a sky high x dim, I had alot of trouble getting on plane with my Mirages and can relate to the cruiser thing, switched to Bravo 1s, MUCH better, a different boat.
The x on my beek is quite conservative, man, Id love to try those SSs ..........doug

floatingphil

Sonic30ss,
Have you spoken to the factory about your setup? They may have the best advise on how to make your combo work.

HOUSTONPROP

limid,let me know what you decide /DARIN

pullmytrigger

Houston- My props are borrowed, they are Mirages, not Mirage Plus, my guy says the difference is the Plus has more cup, what is your view.
I was thinking if I decide to buy these props off the guy I might get them re pitched to drop the the RPM to where I want it but you feel I could drop the RPM and be able to trim higher (for even more bow lift and even less boat in the water) by adding cup??.......sounds good to me!!!...........cool thread, I LOVE talking props .............doug

HOUSTONPROP

yep,The Mirage plus has a larger blade area and more cupping compared to the old style Mirage.And yes e can add cupping to pull the rpm down and add lift./Darin 281-580-PROP

Sonic30ss

Twinn- thanks for the input, do you think the 4 blade will cost top speed, for the ease of getting on plane?

Sutphil- I don't think the factory will be much help now that Jay Ross is gone...noone left who knows about the original Sonics, this combo(engine /drive) was kind of an odd ball from what I understand ...I think the original prop may have been a cleaver.

Darin any info?

pullmytrigger

Sonic- Typically a Bravo1 will cost you a mph or 2, but who knows you may be getting so much prop slip (there is a formula) that the B1s may hook you up and you'll go faster, like in any prop testing, best thing to do.....try it!!
Houston........