429 Swap?

horse sence said:

The problem with putting a 429 / 460 into a 67 with out strengthening the front is
The front end is not built to handle the weight much less any added horse power with out modifing the front end.
A 67 only has one torque box in the front and the other side is simply attached to the floor and the fire wall this causes the frame rail to lift in the front ,so you will need to ad the other torque box to ,you can see this by the door to fender gap on most 67s being wider at the bottom and tighter at the top ,i have had to put a lot of 67 on the frame straightener to fix this. You can ad the other torqur box to strengthen that frame rail .
The next problem is the spring towers ,they crack easily enough with a small block,the extra wright ads more leaverage to the towers and can cause them to lean in or crack with out reinforvement .
Body stress from the extra weight is also a problem it usually causes a crack at the top of the windshield post and on coupes will crack at the quarter behind the quarter window. Frame rail connectors will help stop this.
A small block with a C4 weighs in at around 610 lbs ,a 429/460 with a C6 wrighs in at around 825 pounds so around 215 lbs extra added to those towers a rails
To not reinforce it is a big mistake.
I havent built just one car ,i have built around 175 Mustangs from 64 -73 so i have seen what extra horse power a extra weight does to these cars

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