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ykoutsaris
07-22-2009, 11:14 AM
Hello all! I have a 20' Cigarette that I am midst of re-equipping with an ITS, Bravo XR and IMCO shorty. I run a 454 that should be near to a 525SC power-wise, 1.34 gearing and my prop shaft is now 6" below the bottom of the boat. I have seen from browsing the site that there are many power, drive and prop combos as well as a serious amount of experience present. I would probably get the prop labbed later on to tune it to my boat a little more, but want to get back on the water soon with the prop best suited to delivering good top speed and driveability. Any good advice on prop and pitch would be appreciated.
Cheers,
Yoryi

VetteLT193
07-22-2009, 02:14 PM
25 Mirage + may work. Although, it will probably be kind of hard to get on plane.

You might try calling LipShip to see if you can pick their brains about what they use. They know the Cig hulls well. I think they had built one with a bit less power and same drive, although on an extension box, spinning a 23 M+

zelatore
07-22-2009, 06:50 PM
I'm guessing you'd need more than a 25 in a Mirage+ if you're in the 525 hp range with a shorty. My stock 502/Bravo 1 spun a Mirage+ 25 to 5000 rpm on a 22 Classic and you'd be looking at more power and less drag.


<edit- just saw the gearing was 1.34, so never mind....>

blackhawk
07-22-2009, 07:00 PM
What rpm does the motor need to spin? Your propshaft is pretty deep yet should still be able to run a 3-blade. Assuming you need to run around 5000 rpm I agree a 25 Mirage + is probably a good start. Should put you around 80mph if enough power is there to spool it up to 5000-5200.

ykoutsaris
07-22-2009, 07:43 PM
Thanks for the replies so far. The ITS/XR/shorty combo looks really cool... I'll post pics when I get them. I was running through a 1.5 Bravo with a 27 Mirage spinning about 5200 (too high already) and topping out at 76mph. I added Stainless Marine exhausts (waiting on new SC pulley) and can't let it out anymore... spins too fast. I'd like to spin about 5000. I'm wondering if I'll get back to 27... unfortunately my current 27 is old style and the new propshaft is too big to test. Seeing as my prop is still deepish, is Mirage the way to go or maybe Bravo?
Thanks again,
Yoryi

blackhawk
07-22-2009, 07:58 PM
Thanks for the replies so far. The ITS/XR/shorty combo looks really cool... I'll post pics when I get them. I was running through a 1.5 Bravo with a 27 Mirage spinning about 5200 (too high already) and topping out at 76mph. I added Stainless Marine exhausts (waiting on new SC pulley) and can't let it out anymore... spins too fast. I'd like to spin about 5000. I'm wondering if I'll get back to 27... unfortunately my current 27 is old style and the new propshaft is too big to test. Seeing as my prop is still deepish, is Mirage the way to go or maybe Bravo?
Thanks again,
Yoryi

Going from a 1.5/27 combo to a 1.34/25 combo will lower your rpm a couple hundred so you might be on the money with a 25. However, the ITS/shorty will come into play.

I think a 25-27 is where you will end up depending on slip.

As far as the Mirage/Bravo choice run them both and see what you like better. Mirage will give better bow lift and Bravo more stern lift. Bravo will obviously bite better low-end/mid-range.

VetteLT193
07-22-2009, 08:07 PM
ITS is an extension box..
Cool project ma, like Don said call Phil @ 305-933-9988 and chat with him a bit..
Oh, an we need pictures of the new toy please :) :)

If the ITS is extension box, ask Phil about the Tiger 20'. I think his brother owns it, and when I looked at it to purchase it was spec'd to 500 HP. I'm pretty sure it has the same ratio, and spins a 23" M+. with your extra power I'm guessing 25" but the diameter is smaller so I'd lean towards a bravo. Plus, the Ciggies always seem to run flat Vs. 22 Classics that like a lot of bow lift. So a stock Bravo 26 might be right there.