Gbody frame Notching
- Thread starter 87 monte
- Start date
I suggest against notching your frame as it reduces the cross sectional area of your rear frame rails which reduces their ridgity.
Going with a more practical wheel diameter size would be sensible. These cars were originally designed to be granny cars so there are some limitations imprinted deep into their designs.
I'm not a fan of the big diameter wheels. I'm also not a fan of the 'if you modify it, it won't be as good' generalization.
There are a lot of g-body's out there in existence now with some serious wheel & tire combos that required frame mods. The 'reduces the cross-sectional area of your rear frame rails which reduces their rigidity' statement while accurate merely takes proper mods to overcome the change. Proper fab techniques @ the area sectioned & some additional bracing can return things to OE strength & possibly even surpass it depending on the approach & knowledge/experience of the fabricator.
The strength of the rail is in its height. No change in height = no change in strength (if material remains unchanged).
The rigidity of the OE rail can be called 'subjective' @ best. Functional? Absolutely. Rigid? Not exactly.
It's widely known that during the metric era of car building, GM was focused on cost savings & weight reduction (so the underpowered smaller drivetrains didn't feel so wimpy). G-bodies never had 'rigid' chassis in rock stock form. Narrowing the rails along w/some proper bracing can yield a strong chassis.
Search for a quality chassis fabricator. Someone w/certification/s & proven work is the way to go vs. the 'I know a guy that can do it cheaper & works out of his carport' option. Check for race car chassis shops or hot-rod builders near your area. Go to Summit Racing & ask some of the counter people if they might know an established fabrication guy. It's likely asking someplace like that or at a local racetrack will help your search.
There are a lot of g-body's out there in existence now with some serious wheel & tire combos that required frame mods. The 'reduces the cross-sectional area of your rear frame rails which reduces their rigidity' statement while accurate merely takes proper mods to overcome the change. Proper fab techniques @ the area sectioned & some additional bracing can return things to OE strength & possibly even surpass it depending on the approach & knowledge/experience of the fabricator.
The strength of the rail is in its height. No change in height = no change in strength (if material remains unchanged).
The rigidity of the OE rail can be called 'subjective' @ best. Functional? Absolutely. Rigid? Not exactly.
It's widely known that during the metric era of car building, GM was focused on cost savings & weight reduction (so the underpowered smaller drivetrains didn't feel so wimpy). G-bodies never had 'rigid' chassis in rock stock form. Narrowing the rails along w/some proper bracing can yield a strong chassis.
Search for a quality chassis fabricator. Someone w/certification/s & proven work is the way to go vs. the 'I know a guy that can do it cheaper & works out of his carport' option. Check for race car chassis shops or hot-rod builders near your area. Go to Summit Racing & ask some of the counter people if they might know an established fabrication guy. It's likely asking someplace like that or at a local racetrack will help your search.
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