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Which bellhousing do I need?

3.6K views 3 replies 3 participants last post by  joshbarnett  
#1 ·
I am in the process of putting together all the pieces I need to swap my Muncie with a Tremec TKX. As part of the swap, I want to replace my bellhousing. I just want to get a regular 621 style BH. The issue I am running into is it seems like the depth of the 621 isn't exactly standardized. Most sellers don't even specify the depth and shrug their shoulders when asked about it. Shouldn't the measure of depth be hugely important when trying to pair a BH with a specific transmission?

Anyway, the sites that do list the depth, have slight discrepancies in it. Here are 2 examples:


Both are 621 style bellhousings, but one lists the depth at 6.250 In, while the other at 6.295 in. Well, isn't that a big difference when we're talking about how deep the input shaft will go into the pilot bearing? Will it bottom out on the 6.250 inch one?

Can someone help me understand this?
 
#2 · (Edited)
More than likely they're the same casting. However; I'd take the safe route. Go to your transmission vendor and ask him/her which they recommend. That way if theres an issue, you're covered. As a fallback, Jody Haag (Jody's Transmissions) is a vendor of mine AND Tremec. I know hes done many installs (incl. TKX's) and is incredibly knowledgeable. He doesn't post here, but hes on Team Camaro and Team Chevelle, amongst others. He's a Wholesale Distributor for all of that stuff, and won't sell you something thats incorrect.