C-Beam to tunnel dimensions

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Feb 17, 2026 | 11:04 PM

mikey_vette

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From: San Jose, CA

C-Beam to tunnel dimensions

If anybody happens to have their 4+3/D44 car up on the lift and could grab a rough measurement...I'm looking for the distance between the top (or bottom) of the C beam to the top of the trans tunnel at the point where the front mounting bolts through. It's one measurement I forgot to take before pulling the drivetrain; now starting the mockup of my LS3/TR6060 swap and trying to figure out where the C beam should land at the front.

Feb 18, 2026 | 08:14 PM

Tyler Graney

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I have an 86 4+3, but it's stored a few hours away. I do go over there occasionally though so I'll keep this in mind. Might be 1-3 weeks though. Let me know if you get it before then.

Feb 18, 2026 | 08:36 PM

mikey_vette

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Quote:

Originally Posted by Tyler Graney

I have an 86 4+3, but it's stored a few hours away. I do go over there occasionally though so I'll keep this in mind. Might be 1-3 weeks though. Let me know if you get it before then.

Thanks Tyler! Any measurements you can grab would be helpful to me. I've got an idea on c-beam to transmission output shaft placement, but, as I mounted the motor/transmission pretty low in the car, want to cross verify that I'm not putting too much angle on the rear end by pulling the c beam down to meet the transmission. The good news is the delta between the angle of the transmission output shaft and the pinion flange on the rear end is within 0.3 degrees so I think I should be safe.

Feb 18, 2026 | 09:07 PM

Tyler Graney

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Best I can give now is this picture I took a couple years ago. This has the c-beam support kit from Van Steel for scale if you can find the height of those nuts.