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Re: poly bellhousing bolt pattern vs later engine pattern

From: Jeffc
Remote Name:
Date: January 19, 2004


The B and RB engines (361 to 440) all share bolt patterns, the A and LA blocks all share bolt patterns (old hemi's included with A engines), there are some exeptions having to do with early 50s engines that have bells as part of the engine castings. B/RB and A/LA engines do not cross...... Now, there is a differance in crank, 61 and early cranks are longer, so are not a "just" swap in, the case is still a cross bolt however. In the case of the small blocks ( early Hemi, A and LA) adapter plates can be used, but none to date are for the B/RB engines-- included in the crank change is going from a 8 bolt crank to the 6 bolt at the flange which is standard 62 and up. One other thing on cranks, after 67 the hole that holds the converter is larger and a spacer must be used if bolting to a pre 67 converter and the LA 360 engine has a exturnal balanced crank, so has to have a balance to engine flywheel or converter (or BM flexplate).


Last changed: May 04, 2010