Question: Ride Height

[Jabby]

Hi all,

I always thought my 1968 'vette rode too high. Checking in the Corvette Assembly manual it specifies the ride height, both front and back as a "J" and "K" measurement which is determined by the engine, transmission, and accessories. The front measurement is about 8.25in. The question I have is regarding the note which reads: "Measure "J" & "K" from the underside of the sill molding (appearance line) to the ground." What's the "sill molding"? If it's the side molding, why didn't they say that? Measuring from that, the car sits about right, but I have 3+ inches of clearance from the top of the front tire to the top of the fender opening which just looks wrong in my opinion. If I measure from the bottom of the fender/door area (which could be the door sill) it is indeed too high.

Hopefully, someone has figured this out and can help.

Thanks.

 

[6880 Mike]

I am assuming the GM name for rocker panel is "sill molding."

If the rear of the car appears to be sitting too high, you can adjust the rear spring bolts to lower it. If memory serves, letting out the nuts on the spring bolts lowers the rear.

I may have that exactly backwards.

 

[JohnZ]

The "J" and "K" height measurements are taken from the bottom flange of the rocker molding, but they're directly affected by tire diameter; the dimensions in the manual are only valid with the original production tire size.

The correct way to measure ride height, independent of tire size effects, is to use the "Z" and "D" height measurements shown in UPC 3 and UPC 4 in the Assembly Manual. Those are suspension height measurements, which will tell you if the spring heights are in spec.

 

[bagger]

Hi Jabby,

Replaced my rear suspension and used the stock bolts. I got a full nut on them. The rebuild lifted my rear up a little but I like it that way. Gives it more of an aggressive look. My opinion is set the ride height where you like it and align the front and rear end and enjoy the ride.

 

[rgtrough]

Hey Jabby if I remember correctly the diameter of the original wheels and tires were some where around 28.3". I'm sure someone on here knows for certain. I also have too much height but I have shed so much weight off of mine I will need lowering springs.