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smokediver
10-12-2008, 08:17 PM
Has anyone raised up their engine / x dimension ? maybe 2 or 3 inches ?alpha gen2 350 mag mpi , 18 classic ... was thinking about a little winter ( the one bad boating week we have :biggrin.:) project .. I know there are going to be some hatch mods and exhaust routing but what are the pro's and con's ? thanks in advance !

BlownCrewCab
10-12-2008, 08:43 PM
My 18 barrel back(408 smallblock with a bravo1) had a 3" high X dim. Going straight and fast was a friggin ball, anything slow speed suffered greatly. sometimes it meant coming off plane to get a bite for the prop, I Tried 3,4,5 blade props, I had to put a 1" spacer to fix it, If I where you I wouldn't go up more than 2" (although mine was a true V, I assume yours has the round bottom)

BUIZILLA
10-12-2008, 08:55 PM
IMO, up 2 1/4 on an Alpha is the ticket...

BigGrizzly
10-13-2008, 09:44 AM
My personal opinion is do the SS or Imco shorty. I don't like raising the CG any higher. As for Blown CC that V was a problem for you with the ventilation issue. Yes Buiz's did rock.

zimm17
10-13-2008, 12:41 PM
A shorty is way easier to do. How would you raise your drive height otherwise?

I don't see a listing for a shorty alpha drive.... so a bravo swap on top of it... might not be worth it.

The Hedgehog
10-13-2008, 05:55 PM
Ditto on the shorty/alpha. Steven Whitney can tell you all about the shorty on the 18. If you raise in and don't like it you are SOL. With a shorty you can always space back down. Plus raising it will create the need to bubble the hatch.

I had a nice uncut transom on my X a couple of years ago. I am so glad I went with the stock X

BUIZILLA
10-13-2008, 06:11 PM
An Alpa SS is 2 3/4" shorter.. about 1/2" too short...

smokediver
10-14-2008, 05:33 AM
I hear you Jim ! I don't see why I would be SOL ? I could always go back to original if need be , it's just work ! My plan is to go up 2(ish) inches , add the new chevy bowtie heads with 1.6 rockers , and new exhaust ... I am going to do them in stages so other people can get an idea of what to do and not to do ... should be a learning experience .. I am interested to see how the newer heads are going to do . Horsepower with lower lift cams have looked pretty good ...

zimm17
10-14-2008, 05:54 AM
I hear you Jim ! I don't see why I would be SOL ? I could always go back to original if need be , it's just work ! My plan is to go up 2(ish) inches , add the new chevy bowtie heads with 1.6 rockers , and new exhaust ... I am going to do them in stages so other people can get an idea of what to do and not to do ... should be a learning experience .. I am interested to see how the newer heads are going to do . Horsepower with lower lift cams have looked pretty good ...


Ummm... Maybe I'm confused on "x-dimension", but how in the world can you raise and lower your engine without changing the huge whole in your transom for the drive and still change your height of the prop shaft :confused::confused::confused:

The Hedgehog
10-14-2008, 06:54 AM
Ummm... Maybe I'm confused on "x-dimension", but how in the world can you raise and lower your engine without changing the huge whole in your transom for the drive and still change your height of the prop shaft :confused::confused::confused:

Ah man, its no big deal as long as you have enough time to pull out all of your stuff, reglass your transom, get a jig, recut your transom and put it all back in.. Other than the days of work required for that, no big deal.


Or you could spend the 30 minutes to throw on a shorty. Maybe a little more for a ss

SilverBack
10-15-2008, 11:01 AM
You don't have to reglass and cut a new hole in your transom to raise your X. You can just add a 3 inch raised extension box like I did. That and the steering was the easiest mod that I made with my boat this year. raise your motor mounts and add the box and there you go. I know that my boat is a whole different setup but it jumps up on plane with no problem and has no handling quirks. It drives and rides great. I think that the 12 inch setback helps too. I have not had any chine walking problems at all. Now that Mark Boos is doing my engine and I am going to the HP500 intake and inline intercooler I think my troubles are behind me!!

smokediver
10-15-2008, 06:08 PM
I wonder if an alpha woud bolt up to a stand off box .. anyone ?

BlownCrewCab
10-15-2008, 06:17 PM
Yes, same foot print as a Bravo but two less bolts at the top.....

smokediver
10-15-2008, 07:47 PM
ahhhh... but then you need a full hydraulic steering setup ?

VetteLT193
10-16-2008, 07:10 AM
ahhhh... but then you need a full hydraulic steering setup ?

yes, I don't think any of them have room for the tiller arm.

I think all of the boxes require the engine moved too, and I think you wind up neutral to where you were before (but I could be wrong). meaning, you set the drive back and move it up and the prop is in the same spot it was in the water overall.

oh, and they aren't cheap either :eek: it would probably cost neutral to just upgrade to a nice used shorty bravo.

osur866
10-16-2008, 09:33 AM
Ditto on the shorty/alpha. Steven Whitney can tell you all about the shorty on the 18. If you raise in and don't like it you are SOL. With a shorty you can always space back down. Plus raising it will create the need to bubble the hatch.

I had a nice uncut transom on my X a couple of years ago. I am so glad I went with the stock X
Yep I did the -2" imco and it would be the only way i'd do it, leave the engine in the stock location put a -2" shorty on with 475hp and it'll be more than enough!! Steve

harbormaster
10-16-2008, 05:36 PM
We bought the last of the stellings boxes and have them i stock

Donziweasel
10-16-2008, 05:42 PM
According to some other members, an SS lower will not bolt directly up to an Alpha without serious mods. Something to think about.