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WOT-sup
08-16-2002, 06:26 PM
After a year and a half of sitting in the garage, finally had Day 2 and 3 of meaningful progress. Working with a good glass guy and learning a lot. Got the transom filled and glassed (gimbal and exhaust cut outs), glassed over most of the port-side helm and got fwd and aft bulkheads for fuel bay cut and installed.

May have an opportunity next Tuesday to get it in to a local performance marine shop that has alignment tool/jig for the Alpha One that is going on it.

QUESTION- Since the initial engine is a 5.0 liter (sitting in the garage), but a 350 ci will likely follow , how high can I raised the outdrive 'x' dimension to accommodate the 350 with a reasonable sized mfld/ carb and not have to cut a hole in the hatch for vertical clearance???????

Will use the 'search' function this weekend and read up on 'x'. Any other inputs out there regarding this????

Will try to post a few pics of the boat and.....try to remember to log off and not stay on for a month at a pop :rolleyes:

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Doug L.
08-17-2002, 10:49 AM
You got mail

harbormaster
08-17-2002, 12:02 PM
Hey Doug, How about sharing your response with the rest of the class?

Doug L.
08-17-2002, 12:24 PM
Hi Scot,
I didn't have much to say about the X Dim.
But I would go a min. 3.5" use a solid nose cone
and block of top two water inlet holes.Use tear-
drop bumps for the risers and a nice scoop for
carb facing forward. :D :D :D
Doug

HP 600SC
08-17-2002, 01:44 PM
I think you better measure it a couple of times
3 1/2 seems too high to make everything work.

Doug L.
08-17-2002, 03:46 PM
I have 4.5 to lip on the haul you would have to give up the rear lift ring. You couldn't use the
gil exhaust risers that are on my boat.
It might work, be a bitch if it didn't. eek!
PS: Ted did you know that Cig added a pad to the 20? How is yours coming along?
Doug

BERTRAM BOY
08-17-2002, 06:07 PM
+3.5 inches won't even think about clearing the hatch.
You'll have to cut the hatch to clear the flame arrestor, the exhaust manifolds, and maybe the distributor.......
How do I know this?

BERTRAM BOY :D :D :D

Doug L.
08-17-2002, 07:23 PM
Yep
2" from top of plug wire to lip of deck.
Looks like time for a SS.
Doug

HP 600SC
08-17-2002, 08:46 PM
Doug....I did not know that......cool!
I heard that the 20 is squirly at speeds over 72.
It is going slow right now.....I have been in your
neighborhood many times for the Indy car races!!
and the old twin 200's ....rember them? my brother
raced in them for many years.
Beautiful area.

WOT-sup
08-19-2002, 07:45 AM
What an education reading thru 'x dimension' in 'search'.

Next question: without cutting the hatch ('72 18' classic), can you get enough air to the engine for a 350 to put out 300HP or so?? I would like to keep the stock look.

Am I correct in thinking that a prefered way to get gain a few mph (keeping original hatch) would be keep the 'stock x'height (which would give vertical clearance and good CG) and start looking for an Alpha SS (to raise the 'apparent x')?????

Gather that an SS will take more HP than an Alpha, so at about what HP point does an uncut hatch start to run out of breathing capacity?????

Woodsy
08-19-2002, 07:56 AM
Just my opinion...

I would seriously reconsider the Alpha setup. You are starting off with a 305, going to a 300hp 350 chevy then where? More than likely you will be playing with that as well. I would go with a Bravo setup, set the X dimension 1" to 2" higher, and go from there.

1. Bravo durability with a SBC is virtually bulletproof.

2. Bravo parts & availability

3. Alpha SS drives are rarer than BlackHawks, if it breaks, your screwed!

NEW Bravo Gimbals are $1850, and NEW bravo drives are around $3000 sell the
Alpha stuff to offset the cost...

Woodsy Von Donzi
:D :D

Ranman
08-19-2002, 08:07 AM
I'm with Woodsy on this one. My 18 has a Bravo One with 300HP and though it's overkill, the peace of mind is nice. With regular maintenance, the Bravo will last forever behind a small block 18. Also, my 18 Bravo handles MUCH better than my 18 Alpha did. Lastly, If I ever repower and want to step up the horsepower, I'm good up to around 450-500 with the B1. Sell the Alpha to offset the cost and spend the extra jack to go with a Bravo. If you don't, you'll be kicking yourself in the ass in the near future for not doing it up front. Good luck with the project.

CDMA
08-19-2002, 08:44 AM
Having run a few ( Volvo, alpha, and bravo) on an 18 I can say that the Bravo is night and day superior in every aspect. However if anyone knows neededing (is that a word?) to do things based on a budget it is me and I completely understand where you are coming from. All
I can say is that I lived and I learned and I feel so strongly in the superiority of the Bravo compared to other options that if I had to do it over again I would have sacrificed an entire season of Donzi'ing to save the money to do the Bravo the first time around.

That being said. The Alpha will work well enough and you can also be very happy with it. There are plently of satisfied people out there with SBC alpha boats.

Chris

WOT-sup
08-19-2002, 08:41 PM
Good input, got the wheels turning, thanks all. Even though the 5.0/Alpha is there, it doesn't have to be. Stay tuned.