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Bob Putnam · 05-20-05, 08:17 AM

[ QUOTE ]
Ive started working on a custom chassis on paper. This is not a gt40, but it is similar. This chassis will be made to specific length/width/height to fit within a pre-existing body.

Ive reviewed some other chassis designs and it seems that where I put X-brace supporting, I could have used 1 diagonal bar, but would 1 diagonal bar really give as much support as the X? Am I just adding dead weight by using so many X's?

One of my main concerns is chassis rigidity, but another main concern is to make the chassis as light as possible.

Another problem is that under the passenger and driver's seats is one large X on each side...is this sufficient for a rigid structure?

[/ QUOTE ]

X's are not necessary unless the ratio of the length to tube diameter excedes roughly 30. Your design's main problem is that the section under the door feeds the loads into unbraced points, putting the vertical tubes into bending mode..
Your tunnel does very little if it doesn't feed loads into the front and rear sections.

Unfortunately, there seem to be many other problems too...

At this point, you might consider investing in Racing and Sports Car Chassis Design by Michael Costin. It's the best basic book for chassis I've seen. Amazon's got some used ones.

05-20-05, 08:17 AM	#4 (permalink)
Bob Putnam A Tenth Join Date: Sep 2001 GT40: New Britain, CT Posts: 192 Rep Power: 9	Re: Review this chassis design please [ QUOTE ] Ive started working on a custom chassis on paper. This is not a gt40, but it is similar. This chassis will be made to specific length/width/height to fit within a pre-existing body. Ive reviewed some other chassis designs and it seems that where I put X-brace supporting, I could have used 1 diagonal bar, but would 1 diagonal bar really give as much support as the X? Am I just adding dead weight by using so many X's? One of my main concerns is chassis rigidity, but another main concern is to make the chassis as light as possible. Another problem is that under the passenger and driver's seats is one large X on each side...is this sufficient for a rigid structure? [/ QUOTE ] X's are not necessary unless the ratio of the length to tube diameter excedes roughly 30. Your design's main problem is that the section under the door feeds the loads into unbraced points, putting the vertical tubes into bending mode.. Your tunnel does very little if it doesn't feed loads into the front and rear sections. Unfortunately, there seem to be many other problems too... At this point, you might consider investing in Racing and Sports Car Chassis Design by Michael Costin. It's the best basic book for chassis I've seen. Amazon's got some used ones.