91turbo2

Long story but I have to replace the frame mounts on my 74. I bought a couple of frame cuts from a different vette and cleaned the frame up for welding. My question is what is the measurements to make sure these are welded in the correct spot before I put the engine in? Such as distance from a set point like the steering box. Here are a couple pics to help show what I'm talking about.

TimAT

You need to get a frame dimension diagram. And then level the frame, grab your trammel points and tape measure then matching the dimensions on the diagram to your frame.
Someone may have a better plan, but that's how I see it.

doorgunner

I'm wondering if it's possible to safely move the "new" mounts FORWARD a certain amount in order to have a larger air gap between the firewall and the rear of the engine to help keep the cabin cooler/allow room for a heat shield to be installed between the engine and the firewall.....(just thinking out loud/planning ahead...LOL)

Alan 71

Hi 91,
The AIM has a page for Frame Assembly that has dimensions on it.
There is a gage hole 'A' that appears to be used to locate the engine mounts. UPC2 Sheet A1
There is also a frame diagram in the Chassis Service Manual that has dimensions for locating the engine mounts.
What year are you working on?
Do you have either an AIM or CSM?
Regards,
Alan

speedreed8

this may help some, i think this is a 69 though......

91turbo2

Not sure it would be worth it, that would throw off the transmission mount, driveshaft, etc.

In all honesty I thought this would be pretty straight forward. With the metal tabs on the top, bottom, and sides I don't have to worry about canter because it will only go on way way. I just figured I could measure the distance from something like the steering box.

Thank you very much for the diagrams. Would the frame dimensions ne the same on my 74?