Author Topic: th350 bellhousing issue*  (Read 13253 times)

Offline greatdane

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th350 bellhousing issue*
« on: July 10, 2010, 10:05:35 pm »
OK, my truck originally had a th350c lockup in it. I traded that for a non-lockup. Well today I go to bolt the trans to my sbc 355 and realized that this trans looks different. The bellhousing doesn't have a bolt hole at the very top point. Well I stopped there to investigate this issue.  Is it a car trans of what? The guy I traded doesn't remember what it came out of! Of coarse! Will it work? Can you just skip that top hole!? Or am I screwed???
'84 GMC Sierra Classic SWB 2WD
'08 Chevy Silverado Ext Cab 2WD
'74 AMC Matador 2dr Coupe

Offline Irish_Alley

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Re: th350 bellhousing issue*
« Reply #1 on: July 10, 2010, 11:29:01 pm »
all you need is the six bolts
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

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Offline Lt.Del

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Re: th350 bellhousing issue*
« Reply #2 on: July 10, 2010, 11:51:24 pm »
don't sweat it.  just put the bolts you can in it.  i went from a th350 to a th350c lock up.  I don't recall worrying about  all the holes --i have enough in it.

Offline HAULIN IT

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Re: th350 bellhousing issue*
« Reply #3 on: July 11, 2010, 12:42:18 am »
Actually many blocks don't have the boss/hole drilled for the top bolt...Put the tranny in there & get it goin'. Lorne

Offline VileZambonie

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Re: th350 bellhousing issue*
« Reply #4 on: July 11, 2010, 05:58:23 am »
Sounds like you have a dual bolt pattern bellhousing (BOP)
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Offline greatdane

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Re: th350 bellhousing issue*
« Reply #5 on: July 11, 2010, 08:09:16 am »
Sounds like you have a dual bolt pattern bellhousing(BOP)
whats bop? I just woke up! lol
« Last Edit: July 11, 2010, 08:11:36 am by greatdane »
'84 GMC Sierra Classic SWB 2WD
'08 Chevy Silverado Ext Cab 2WD
'74 AMC Matador 2dr Coupe

Offline VileZambonie

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Re: th350 bellhousing issue*
« Reply #6 on: July 11, 2010, 08:18:23 am »
buick olds pontiac
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Offline greatdane

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Re: th350 bellhousing issue*
« Reply #7 on: July 11, 2010, 08:33:03 am »
I guess the guts are all the same? Just a different bolt pattern? I wish I would have noticed sooner....
'84 GMC Sierra Classic SWB 2WD
'08 Chevy Silverado Ext Cab 2WD
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Offline 123 pugsy

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Re: th350 bellhousing issue*
« Reply #8 on: July 11, 2010, 09:13:49 am »
Guts are the same.

Nothing wrong with what you have.
Looks are only skin deep you know. :P
Pugsy
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Offline Swims350

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Re: th350 bellhousing issue*
« Reply #9 on: July 11, 2010, 01:38:34 pm »
I was thinking the same bop but they usually have a valley in the trans top, and extra holes with long ears to bolt up on top as for the top one, I've seen some blocks have a hole, but don't think I've ever seen a trans have the hole for it, nor have I ever taken one apart that was bolted up there.

I like to look as it as the house roof and walls as that's how chevy bellhousing as made, look at it this way, you need to anchor the bottom and top of the walls, bottom to the floor, and top to the roof, then you tie in the middle of the roof like a roof truss support does, and nothing at the peak of the roof/ridge. So you got two bolts on each side, one bottom vertical surface, one top, thus being bottom and top of the wall, and one on each side midway of the sloped roof. 6 total that's it.
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Offline HAULIN IT

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Re: th350 bellhousing issue*
« Reply #10 on: July 11, 2010, 06:53:49 pm »
Guys, What it sounds like to me by his description...he is referring to is that some engines (more so than trannys) have a bolt at the very top center on the regular Chevy pattern, 7 bolts instead of the normal 6. As mentioned, the BOPC bellhousing is dipped in the center, they also just have 6...the upper 4 are in different locations than the Chevy bell housing. The multi-bell that Vile mentioned has 10 bolt holes (the guidepins & the bottom holes are in the same locations, Chevy & BOPC).
 Greatdane, Post a pic, but by your description, to me it sounds like your good to go & really have "the correct" bell housing that is in all of the "normal" Chevy V8 vehicles. Lorne

Offline VileZambonie

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Re: th350 bellhousing issue*
« Reply #11 on: July 11, 2010, 07:30:39 pm »
So you're saying you just don't have a bolt that goes at the top of the bellhousing then?



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Offline VileZambonie

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Re: th350 bellhousing issue*
« Reply #12 on: July 11, 2010, 07:32:09 pm »
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              ⌠¯¯¯¯¯'   [☼===☼]
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74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline HAULIN IT

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Re: th350 bellhousing issue*
« Reply #13 on: July 11, 2010, 08:17:36 pm »
That is what I'm making out of his description. Like Swims said, I have several blocks drilled & tapped, but the tranny having the hole is very odd...seems to me I had a Blue stickshift bell housing (maybe an iron duke H-body) maybe it was a truck, that had the top hole, who knows?  Greatdane, The one with the pencil in it? Lorne

Offline greatdane

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Re: th350 bellhousing issue*
« Reply #14 on: July 11, 2010, 08:59:17 pm »
So you're saying you just don't have a bolt that goes at the top of the bellhousing then?




Mine looks like the top one! My original trans had the top bolt hole?! But this one doesnt? I think I am OK though!
« Last Edit: July 11, 2010, 09:04:39 pm by greatdane »
'84 GMC Sierra Classic SWB 2WD
'08 Chevy Silverado Ext Cab 2WD
'74 AMC Matador 2dr Coupe