Looking underneath the car it appears the front chassis rails just deminish at about the back of the doors. The rear chassis goes from the rear tow hooks up and to the sides of the car but there doesn't seem to be much connecting the front chassis to the rear chassis (except maybe the semi boxing going where the back seat clips in. Am I correct in thinking it's the body that connects the rear chassis to the front chassis? Reason I ask is I'm now wondering if bolting my battery earth to the rear chassis rails will be good enough connectivity to the front chassis rails where I have the chassis earth to engine earth going to one of the bell housing bolt. Also I was wondering if anyone has thought of strenghting that part of car up with some sort of k-member linking the rear and front chassis.
Re Front and Rear Chasis I guess the question you could be asking is whether anyone on the forum has suffered from flexing in their chasis. Mine certainly doesn't but I think it has always been driven on sealed roads. Shame on anyone who takes their Z on dirt roads! With the reading I have done apparently the designers of the car had to make the body VERY rigid so that they could use the suspension setup that they used. Not many vehicles these days have a full chasis - only a few four wheel drives. With regard to the earthing question try what you have come up with and see if the starter motor still does its job OK. Good luck.
Flex My car flex's heaps. Because it's so low I have to jack it up with the normal jack a bit, before I can slide the trolley jack under to jack it from the cross member. Whilst using the factory jack on the side of the car, I can't close the doors of the car or close the bonnet if it's been left up. If it's been left down the bonnet will flex and stick up a good 5 mm on one side above the fender. The boot lid also won't close if it's been left up and I try shutting it. I can also hear interior trim panels creaking and what not when I go up and down the lime stone drive way. It's rocky and uneven.
The TT's extra weight must make the difference.... ....as my NA does not suffer as badly from body twist with a jack under it, ie my doors, boot lid and bonnet are not as affected (the door on the side being lifted may clunk slightly when closing, with the door catch not as squarely lined up, but thats it
With a jack under one corner of my car.....>> I can still open and close both doors, the bonnet and the hatch without any problems, except for the same symptom that Gaza mentioned of the lifted door making a slight clunk when closing.
Bit of flex in mine But no probs shutting doors or tail. Can't say about the bonnet - too much crap in the way to try and shut it. Cheers, Dean
My NA is the same - no flex I can detect. In fact, I can't seem to put the car on 4 jack stands (like when I changed the gearbox oil a few months ago) and actually get it to rest on all four stands on a flat surface. It rests on 3 OK but there is always a gap to one jackstand. I mean, there must be some flex, I just can't detect it. I wonder if it's TTs or something else. cheers, Peter
I'll have to come clean Having said that my car doesn't flex earlier was based on me driving it. It just feels tight. I've driven a lot of cars in forty years and it's just something you feel and it was that "feel" that the car had when I first test drove it. But now we have a test!! So I went down and jacked up the front passengers' side until the wheel was off the ground and then opened and closed the passengers' door and it closed but caught slightly on the latch - definately flex!! If I pushed down slightly on the door it closed as normal. Hood and boot were still perfecly aligned as was the drivers' door. I jacked up on the drivers' side and to my relief I got the same results with the drivers' side door catching slightly. My son had a Corolla which had had a frontal at some time and if you jacked up the front passengers side, the door went way out of alignment but still not bad on the drivers side. I jacked up the rear passenger wheel and everyting was OK. My car has done 154,000 Km so I guess you are going to get something happen but my VH Commodore jacks up without affecting the doors but has mainly only ever driven on tar and very carefully on dirt. Jacking the Z up until the wheel is off the ground would put quite a stain on it and that lack of roof would make a difference. Also the stiff suspensions that these cars have would put a lot more strain on the body than a standard Commodore. Sorry guys - I'm getting a little carried away here but just thought I would qualify my earlier assertion.
I used to have a VW golf (an early model one) It specifically said in the manual that all doors must be closed before jacking. Of course I ignored that and jacked it, All the doors wouldnt close !!! Figured I had better pay attention next time !!:wacko:
I know for a fact you were not the only one that had that issue with the golfs. Mate of mine couldn't figure out what happened till I told him.
The chassis rails do not meet ->>> the construction is called "monocoque" pronounced mono cock. The strength is in the design of the shell hence a "slick top" will have less flex than a "targa top" irespective of being a 2 seater or 2+2. Very few modern cars use full chassis design because of crumple zones being built in. Some utes will have a full chassis, "one tonners" are the best example. 4wd's may have full chassis hence the are detremental to the passenger (they get hurts due to sudden stop) crumple zones slow the process. To reduce flex the body could be completely seam welded and have roll cage fitted but the roll cage should be tied to the suspensions / shock absorber points. Flex in itself is not a bad thing as the four points of contact with the road surface tend to stay put. PLEASE remember that the more rigid the body, the better the suspension has to be and the more likely it is to go sideways in some cases out of control hence "Drifting". Which by the way is not a new sport have a look at some of the earlier racing cars and two wheel and four wheel drifts were common, Rally drivers ahve been drifting for years. Have Fun Cove
Mine doesn't flex much at all.... no problems with any panels/doors not aligning. I can jack both front and back wheels off the ground easily from one corner.
Speak for yourself Kalus - I was actually thinking Z32 TT :thumbsup: - Oh OK maybe Fiat Bambino but one can dream can't they? :|
