Cracks in front frame rails under K frame mounting points

[not so famous bob]

If you look at my pictures I added plates on the sides.

No plate on bottom since that's where K-member bolts to.

no big deal to put them under the bolt /frame area , like I said , 68 hemi barracudas had the 1/2'' spacers under there from the Hurst factory .

 

[j-c-c-62]

no big deal to put them under the bolt /frame area , like I said , 68 hemi barracudas had the 1/2'' spacers under there from the Hurst factory .

I'm not convinced yet the side plates will prevent future cracking in the area of the first crack.
I'm also wondering if inadequately torqued mounting bolts (4) might have played a part here in allowing some movement and the resulting extra shock loading?
The fact it appears one crack started at the spot weld indicates that possibility.

 

[autoxcuda]

no big deal to put them under the bolt /frame area , like I said , 68 hemi barracudas had the 1/2'' spacers under there from the Hurst factory .

That will change the relationship of the motor and LCA (lower control arm) to the body. Now 1/4" plate isn't much. But in my mind I didn't what to raise my center of gravity any, although realistically insignificant. It also slightly raises the UCA pickup point that I don't want for handling (again probably insignificant)

 

[dvw]

Trust me. Nothing gets the front end dropped out of the air as often as my racecar. It wheelies 1-2 foot most every pass. Nearly 1100 passes. Occasionally to high. It’s had the pan and the diaper repaired more than once. Last time even cracked the K frame. No damage to either rail. Weld areas are still perfect.
Doug

 

[not so famous bob]

That will change the relationship of the motor and LCA (lower control arm) to the body. Now 1/4" plate isn't much. But in my mind I didn't what to raise my center of gravity any, although realistically insignificant. It also slightly raises the UCA pickup point that I don't want for handling (again probably insignificant)

they did it for engine clearance , worked well...

 

[j-c-c-62]

Actually, on further consideration and review of the pictures, IMO any drilling that goes thru the uncracked threaded inner backing plate would likely only weaken the entire mounting system, even after trying to weld back up the drilled hole, irrespective of any of the assumed benefits the drilled hole has in preventing additional crack propagation.
Meaning, don't bother to drill here at the end of the crack.