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Ideas, input for diff brace

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Old 05-21-10, 10:17 PM
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Ideas, input for diff brace

Looking for input, ideas for a diff support/cradle and trans mount so I can completely eliminate the PPF. I realize there are some options out there but I am more interested a well engineered solution, and I like making stuff.

So what I have been thinking of:
- basically two cradles, one behind the lower diff mounted to the lower diff screws (replace with longer screws through urethane bush), the other utilizing the traditional mounting points, but more of a cradle.
- it needs to install with minimum modification to the chassis/subframe
- it needs to be lighter then the PPF otherwise what is the point.
- obviously it needs to be indestructible =)

Resources: Cad/Cam, CNC, Mill, Lathe, TIG

I will be dropping my rear subframe tomorrow and starting on the project, and hope to have a design finalized within 15 days, built and installed by the 10th of June.
Old 05-21-10, 10:51 PM
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needs more track time

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The V8 guys have made some nice and effective diff braces. Might want to research them.
Old 05-22-10, 02:33 AM
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I like the idea of adding bushings to a brace.
Old 05-22-10, 09:23 AM
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Not sure why eliminating the PPF is such a good idea - it's one of the coolest design features on the FD. And it's not particularly heavy either.

Dale
Old 05-22-10, 11:07 AM
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Originally Posted by DaleClark
Not sure why eliminating the PPF is such a good idea - it's one of the coolest design features on the FD. And it's not particularly heavy either.

Dale
Nothing wrong with the PPF for stock or slightly higher HP levels, however it is prone to failure over 400 rwhp. I also have to replace my rear subframe anyways so its the perfect time address potential issues.
Old 05-22-10, 11:26 AM
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needs more track time

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Originally Posted by TitaniumCranium
Nothing wrong with the PPF for stock or slightly higher HP levels, however it is prone to failure over 400 rwhp.
I don't buy that at all. It can break w/ massive wheel hop but I've never heard of anyone breaking a PPF just b/c they are running over xx HP.
Old 05-22-10, 11:52 AM
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Originally Posted by gracer7-rx7
I don't buy that at all. It can break w/ massive wheel hop but I've never heard of anyone breaking a PPF just b/c they are running over xx HP.
I'm not trying to sell it either and I apologize for making a vague statement.
Old 05-23-10, 08:36 PM
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everything is out an I have started modeling some different brackets. I plan on analyzing them based on a 500ft/lb engine torque with stock trans / diff ratios. Here is the start of the back bracket that will mount thru the lower 4 diff cover bolts
Attached Thumbnails Ideas, input for diff brace-diffbrace3.jpg  
Old 05-23-10, 10:22 PM
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NY great idea

i agree 100% with you. I broke my ppf in 9 spot's 6 month ago. It was so bad my tranny slammed through my tranny tunnel , my shifter was almost 7 inch's higher then norm . it's a great idea . ive also have been trying some idea's myself for the same reason but due to my wife and i splitting up i had to put them on hold i think's it's about time some did something about this !! . I also blew my rear up so bad i could put my whole hand in the ear's of my rear end where the axle"s go into the ham on both side's. !!!! maybe we could swap idea's and fix this on going problem with the fd all together my name is pat .goodluck dude
Old 05-24-10, 09:22 PM
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I have a really crappy model of the diff done to help with visualization and started on an assembly. The mounting points are correct for the diff and oem mount, the chassis points wont be as accurate as it is not as critical. I mentioned 500 ftlb torque but have not decided yet...any suggestions? Keep in mind that is strictly a static load, I will apply a safety factor on top of that which will compensate for shock loading.
Attached Thumbnails Ideas, input for diff brace-assem1.jpg   Ideas, input for diff brace-assem1-loaded.jpg  
Old 05-24-10, 09:32 PM
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justin samberg has a very nice diff cradle that eliminates the ppf. On the diff side anyways. You would still have to support the tranny.
Old 05-24-10, 09:36 PM
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Originally Posted by Cgotto6
justin samberg has a very nice diff cradle that eliminates the ppf. On the diff side anyways. You would still have to support the tranny.
I have seen a lot of references to his cradle but haven't found any pics-specs-price for it.
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