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Old 01-03-2010, 10:52 AM
android 211 android 211 is offline
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Location: Miami, Florida
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Default trans crossmember problems

My '69 convertible was a stripped body shell when I pulled it out of a Colorado junkyard many years ago. Recently I dropped in a rebuilt '72 455 and Turbo 400 to replace the long-gone YS 400 and PQ trans. I used '69 perches and engine mounts. I have two crossmembers. One came with the car surprisingly and the other is almost identical and came off a '69 or '70 GP. Those of you who have a convertible know how the crossmember mounts to the frame. My problem is the engine/trans combo is just about an inch too long to allow the clamps that squeeze the rubber insulators to line up with the holes in the frame. It doesn't matter which way I have the crossmember or the tranny mount it doesn't quite line up. The block has five holes. Did I attach the mounts too far forward? Any ideas anyone? I posted this before and got no responses.

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Old 01-03-2010, 11:20 AM
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PontGuy PontGuy is offline
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The crossmember on my 69 vert bolts right up to the frame (does not use the rubber isolators). Using the rear-most holes on the frame the Turbo 400 mounts right up.

A couple of thoughts- convertible crossmembers are not the same as for hardtops because of the box frame. When I bought my car I found the previous owner had a cut-down and bent hardtop crossmember in there that was "made" to work. I ended up replacing it. Make sure you are using a vert crossmember. Also you need a short tailshaft on the TH400.

Walt

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  #3  
Old 08-06-2010, 10:11 PM
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b-man b-man is offline
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You should be using 2-bolt A-body mounts on the block, they're all the same from '64 -'72 for all the 326, 350, 389 & 400 engines. These mounts also work with 455s, even though the 455 '70 -'72 A-body cars used special wider 455-only engine and frame mounts from the factory. I don't think there's any way you can get the mounts bolted on too far back, there only 2 holes you can to bolt them to even though there are 5 holes on a 455 block.

Don't try to use the B-body big Pontiac-style engine mounts that probably came on your 455.

Make sure that your TH400 has a short tail housing, the housing should measure a little over 4" long.

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