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View Full Version : Prop suggestions- re-powered X-18 with 454 bravo 1



Ted S
07-15-2012, 05:24 PM
Just finishing up re-powering my '73 X-18 and need suggestions for a prop. The engine is a 454/330 with some work, it makes approximately 365 HP. The drive is 1:50 ratio Bravo 1. any help will be appreciated. I was thinking a Turbo 1 23 or 24 pitch. Does this make sense?

Ranman
07-16-2012, 09:50 AM
I would think a 24P or 25P would be a good place to start. For instance:

An 18 with a 300 PSHP 350MAG MPI Bravo (1.50:1) will turn a 23 Mirage+ well.

My 18 with a 300 PSHP 350 MAG MPI Bravo (1.65:1) turns a 25P Mirage+ well.

For your setup, you're adding 65 HP but a bit more stern weight. I'm guessing you'll be looking at a 25P 3 blade or thereabouts. Just rember test, test, test any props you can get your hands on.

Also, I am assuming you're running a standard X dimension and a standard Bravo (non-shorty).

Ted S
07-16-2012, 09:48 PM
Thanks for the input. Yes it's a standard Bravo. I have a Mirage Plus 23p I can try first. I think I'll be able to water test it next week(hopefully). In the meantime I'll keep looking for more props to try. From what I've been reading, it seems the Turbo 1 is the most popular prop.

MR MAGOO
07-17-2012, 09:52 AM
I agree with the Mirage, either a 23, if you are going to run around with several people on board, or the 25 if you'll be doing most of the running light. The big block likes the large diameter of the Mirage series.

Ranman
07-17-2012, 10:27 AM
The Turbos are certainly popular. For our boats (16 and 18 Classics and stocker 22's), Mirage+, PP Turbos and Hydromotive Quad IV's seem to be the most popular choices. Not sure how a Turbo will react given your situation with extra junk in the trunk. Best advice is to rry as many as you can get your hands on and see what works best.

Ted S
07-17-2012, 10:00 PM
Thanks for the info. What diameter Mirage + would you suggest? I know with more "junk in the trunk" I would want more lift but what do you think the range should be.

Thanks