The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - 55.2-59 changing drivetrain for 1958 Apache 38

dsraven · 01-18-2024, 10:22 AM

unless you plan to use a side mount engine mount and fab up some brackets for the frame side of things and then fab up a transmission mount as well, and then cut out the original cross member that was used at the rear of the trans, you will need a V8 bell housing for the 350. if you cut out the original trans cross member there can be more frame flx in that area which can affect the cab mounts. I recommend to cut the cross member in such a way that it can be modified to clear the new engine and trans combo, fab up some brackets and weld them to the cut off part in such a way that the cut off section can be bolted back into place after the new engine combo is in the truck. then you retain the strength in the area of the cab mounts.
really, GM made the original mounts and they are still available so if you gotta buy mounts anyway you might as well buy the original ones and spend less time fabbing and more time driviing. the hard part would be finding a V8 bellhousing used, but they are available as a new aftermarket part in worst case scenario.

01-18-2024, 10:22 AM	#15
dsraven Registered User Join Date: Nov 2010 Location: calgary alberta Posts: 7,894	Re: changing drivetrain for 1958 Apache 38 unless you plan to use a side mount engine mount and fab up some brackets for the frame side of things and then fab up a transmission mount as well, and then cut out the original cross member that was used at the rear of the trans, you will need a V8 bell housing for the 350. if you cut out the original trans cross member there can be more frame flx in that area which can affect the cab mounts. I recommend to cut the cross member in such a way that it can be modified to clear the new engine and trans combo, fab up some brackets and weld them to the cut off part in such a way that the cut off section can be bolted back into place after the new engine combo is in the truck. then you retain the strength in the area of the cab mounts. really, GM made the original mounts and they are still available so if you gotta buy mounts anyway you might as well buy the original ones and spend less time fabbing and more time driviing. the hard part would be finding a V8 bellhousing used, but they are available as a new aftermarket part in worst case scenario.