chassis stiffness
 

anybody like to comment on the stiffness of the FD chassis?

when i enter my garage and go slowly over the driveway bump at an angle i feel as though the car is flexing too much. is this just my paranoid imagination? driving my other car over the same driveway it doesnt feel like it's flexing/bending/twisting as much. the FD actually makes like a squeaking (spelling?) sound.

-t

I've driven both my roomate's S2000 and my FD into my same driveway. They both make similar noises and feel the same going in at an angle. The noise is more suspension components anyways.

yea, i notice that when i go over a slight dip on the freeway about about 60mph or so the rear suspension makes like a compressed air releasing sound.

Bushings if it's a squeak.

Compressed air sound? Never heard that from the rear. I'd have to hear it in person.

All 4 of my GAB Super-R's make a quick pneumatic "tshk" sound over bumps. Somewhat like a BOV. I'd imagine thats normal valving noise...

My old BMW had a horrible groaning squeak going over bumps at an angle & at slow speeds. I found an old sway bar bushing was to blame. Then again, that car had nearly 200k on it, and was more noisy than my FD.

Like everyone else said, if you're just getting the noise it's probably a bushing and it might be tricking you into thinking the body is flexing.

You can do the "door open test" which is park one side of the car on a curb and try to open the door on the opposite side. This was how the magazines used to test how flexy convertibles were so I dunno if it'd work in testing a supposedly stiff closed roof car.

how do you do that test??

You park the passenger side wheels on a curb, then you try to open the driver's door. Like, if you're driving along a residential street all you have to do is dip the passenger side wheels into a driveway and then drive up the nicely ramped-up curb, if the curbs are square. Otherwise put the wheels as far up as you can go. With some cars the chassis will flex enough that you can't open the driver's door because the frame has twisted around the door such that it is held in place. I've never tried it with an FD, usually it's easier to do in convertibles or cars with frameless windows.

I guarantee you an FD will pass this test.

Shit, even my Civic will pass the test. ;)

You only want to put one of the passenger wheels on the curb, so that you're putting some twist into the chassis. If you put both passenger wheels on the curb, you're just tilting the whole car.

positive that this passes. its like jacking up a car and putting your spare or whatever on..im sure the doors open.

There are various ways to stiffen the body. Installing a roll cage will stiffen it the most. You can buy stiffening braces/bars as well.

I remember jacking up the rear of the FD on one side (using the spare tire jack at the time) while the front end was on jack stands. I look over and the OPPOSITE SIDE OF THE CAR WAS LIFTING at the same time. I was able to lift the opposite side wheels off the ground, and even bounce the car a little. Had about a one-third second natural periodicity. Never seen another car do THAT before!