The 205 needs to be 31 spline (Ford) or 32 spline (GM). The smaller inputs (10 and 27 spline) are already the weak point in a 203/205 setup (with only a 2:1 ratio), once you nearly triple the torque on the small inputs they won't stand much chance.
CK5
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New doubler?
- Thread starter oatsk5
- Start date
The 205 needs to be 31 spline (Ford) or 32 spline (GM). The smaller inputs (10 and 27 spline) are already the weak point in a 203/205 setup (with only a 2:1 ratio), once you nearly triple the torque on the small inputs they won't stand much chance.
gonefishin
1/2 ton status
Hey with the fig 8 kit I ordered I don't need the adapter for the 205 correct?
You need to get your trans to bolt to the 241, the "adapter" between the 241 and 205 is part of our kit.
Any updates on availability of the round pattern kits?
Haven't made any progress on that lately, we've been super busy. We do have the figure 8 version ready, if you're interested we can swap you a big bearing figure 8 case at no cost on your side and we'd have that kit ready to go.
DeviousK5
1/2 ton status
ok so i have to ask because it isnt clear to me. How is the NP205's input seal retained with this? Ive got a figure 8 pattern 27 spline input pass drop 205 and a 31 spline driver drop np205, i am gonna rob all the guts from the ford case and get it all into the chevy case after the case is machined to accept the larger ford bearing. is there any different pricing for the 31 spline version? and is there a package deal pricing that would include the 3 stick shifter?
The seal would be retained in the plate that's supplied in the kit. However, as of right now, we have no ETA on the availability of these kits as our machine shop is totally slammed with our day to day operations.
DeviousK5
1/2 ton status
well you let me know who you have to sleep with to speed up the process- and ill cheer ya along from the sidelines 
lol. Well how do i stay posted on this, tax money will be here very shortly and i already have my donor parts so...yeah
lol. Well how do i stay posted on this, tax money will be here very shortly and i already have my donor parts so...yeah88bigburb
Registered Member
Any news on this doubler?
At this point there is no plan to proceed with that project.
Get the Magnum Box instead 
gonefishin
1/2 ton status
I am glad I got my 241 doubler when I did! Must be one of the only ord 241/205's out there.
Ned Kelly
1/2 ton status
So, if I read this correctly....
A 1985 and up TH400/np205 in stock form won't work?
If it doesn't work, what would one need to do to make it Magnum compatible?
A 1985 and up TH400/np205 in stock form won't work?
If it doesn't work, what would one need to do to make it Magnum compatible?
The adapter you have doesn't work, you need a TH400/NP208 adapter. The one you have is worth more than the one you need.
We don't make a Magnum for the round pattern 205's, basically they are rare and more useful for other applications. You can drill/tap 8 holes in your case or, what we normally do, is pay shipping both ways and trade your case for a big bearing figure 8 version.
