Minimum Engine Spacing
10-14-2007, 07:05 AM
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Minimum Engine Spacing
I have an old cig with the drive spacing at 25 1/4". I curious if anyone knows if a pair of small blocks would fit. They would replace a pair if I-6's. Thanks for any help.
10-14-2007, 04:08 PM
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Are you measuring prop shaft center to prop shaft center or distance between the transom plates?
Big blocks work on 36" centers in side-by-side applications. Small blocks will work on slightly less, but you may be limiting your exhaust choices.
Staggered engines usually end up on 18" centers and a short stagger about 22" centers.
From your post I suspect you're talking about an old 28' Cigarette that had the Chevy 250 cu.in. 6 cylinder engines with Alpha drives. Yes?
Big blocks work on 36" centers in side-by-side applications. Small blocks will work on slightly less, but you may be limiting your exhaust choices.
Staggered engines usually end up on 18" centers and a short stagger about 22" centers.
From your post I suspect you're talking about an old 28' Cigarette that had the Chevy 250 cu.in. 6 cylinder engines with Alpha drives. Yes?
10-15-2007, 05:25 PM
#8
I know you can atleast go 31" centers ( propshaft ) on small blocks with Gil manifolds. You may even be able to squeeze another inch or so.
I have a buddy that has an older 28 cig. small block boat with stock exhaust & although I am not sure what the centers are I know that the manifolds are all but touching. so some of the guys in the cig. section should be able to tell what the tightests you can go is. I would post your question in there also if you havn't already..
I have a buddy that has an older 28 cig. small block boat with stock exhaust & although I am not sure what the centers are I know that the manifolds are all but touching. so some of the guys in the cig. section should be able to tell what the tightests you can go is. I would post your question in there also if you havn't already..
10-15-2007, 07:43 PM
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32 inch centers with twin 280 TRS packages in a 24 race boat.
This is the exact same hull you have with a 24 Cigarette.
www.bananaboatco.com
This is the exact same hull you have with a 24 Cigarette.
www.bananaboatco.com
Last edited by Top Banana; 10-15-2007 at 07:47 PM.
10-15-2007, 09:58 PM
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Measured my small block setup in the scarab. Propshaft measurement was 31" . Measured @ the dimple in the top of the gimbal ring and it was 31" , thought I had the drives toed but I guess not . Measured between the transoms , 19" . I can barely get my hand between the stock merc manifolds. Alpha transom / drive setup.
