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Forgive my complete lack of knowledge here. I just removed the diagonal frame brace that attaches at the A pillar, runs diagonally and mounts to the top of the frame rail just before the shock mount. While doing so, I spun one of the rivnuts and had to cut the bolt head off to remove it. I am completely unfamiliar with them. I need to know where to get one and what I need to install it. I did quite a bit of research and still have zero understanding of them.
C4 Steck,
Do a search for rivnuts on line, I found some I needed at an auto parts store. I needed 5/16 for mounting a cover on my electric winch on my trailer.
See you tube on how to install without a special tool.
John
1990 white/black #2546
one of a few 4l8OE auto EQ ZR-1's
Thank you! About the same time you posted this, I finally started to figure this out. I noticed the hole in the frame appears countersunk or chamfered. I also found some countersunk splined rivet nuts in stainless online. Now just to figure out the thread size on the original bolts. It appears as though I’m on my way with this.
John, side note: I’ve seen photos of your 4L80 swapped Z pulling the front wheels. Bad ***! My dad just brought home 90 #0115 today. Black over grey. We are loving corvette life right now!
You could choose not to use rivnuts, maybe drill a hole bottom of frame rail use flange nuts and a socket or maybe a window in the rail side and a box wrench to hold the flange nut. A friend does that often when repairing older unibody cars. If you insist on rivnuts see if there's maybe a source to rent a pneumatic installer. I'd think a flange nut to secure them maybe better than a rivnut.
A clever person could use a j-nut fabricating a correct window on the frame rail top side.
Forgive my complete lack of knowledge here. I just removed the diagonal frame brace that attaches at the A pillar, runs diagonally and mounts to the top of the frame rail just before the shock mount. While doing so, I spun one of the rivnuts and had to cut the bolt head off to remove it. I am completely unfamiliar with them. I need to know where to get one and what I need to install it. I did quite a bit of research and still have zero understanding of them.
You can buy a complete kit online that will come in various sizes with appropriate mandrels. I’ll post a pic of my kit tomorrow.
C4 Steck,
I'am glad you like my photo of my car taken in 2017. He is one taken in Jan 2025 almost the same angle but 8 years later.
Even after 8 years she still can almost lift the front wheel off the ground. I removed the prowler front spoiler to make loading the car on my trailer easier. Made
a front scoop to get air into the radiator for cooling.
1990 White/Black #2546
one of a few 4l8OE auto eq ZR-1's
John
C4 Steck,
I'am glad you like my photo of my car taken in 2017. He is one taken in Jan 2025 almost the same angle but 8 years later.
Even after 8 years she still can almost lift the front wheel off the ground. I removed the prowler front spoiler to make loading the car on my trailer easier. Made
a front scoop to get air into the radiator for cooling.
1990 White/Black #2546
one of a few 4l8OE auto eq ZR-1's
John
Very cool, John! That thing sure leaves the line. I also like how the skinnies are sawblades. On a project note, I think I’m probably going to go the rivet nut route I’m just deciding what kit I want to get. So many options from the bolt type, neumatic, etc. I figured I don’t want to cut the frame and a good rivnut will last me another 30 LOL. Time to get this thing painted. I’m going to leave it apart to do the plugs and wires on that side, I’ve got great access right now. Then get that side back together and start pulling the front apart. Going to do opti rebuild, water pump, ICM, and coil and reseal the front, the intake, and oil pan. I was under my dad’s LT4 the other day and I realized that this is not exactly going to be easy. So I’d better get going if the car is to be ready by May.
I have one of the two good bolts to check the thread size on tonight then decide on a good tool or kit. But once I know the size I will narrow it down.
I was able to fish the cut off bolt with whatever factory nut out of the framerail through the inspection hole with a flexible telescoping magnet. Photos are below. I can’t figure out of this is something that was added to the underside of the hole prior to the frame sections being boxed or if it was something inserted after. The size and shape make me think it’s the former because there’s no way this fit through that hole or was flattened to this perfect cylinder shape. I do believe the piece of remnants on the bolt thread in the photo might indicate there was more to what remains on the bolt and it just rotted away. Not sure though.
C4 Steck,
I had my stock 1990 front rims narrowed by Weldcraftwheels.com . Stock rims 9.5 in after they were narrowed they are 6 in with Hoosier Pro street 26X7.50R17 LT tires they are good up to 130 mph. I drive with them year around ( no snow just rain)
Take your time working on your dad's car
John
Frame Rivnuts
