Blooze Own: An F355 Six Speed N* Build Thread (Page 38/126)
ccfiero350
MAR 22, 06:44 PM
Here is the setup, the animations start at ride height, in this instance, the bottom of frame is 5.75" off the ground. Which in most fieros means it's lowered. The wheel/tire combo is 17x9 25mm offset, 255/40/17 tire. I added 3 inches to the fixed length rear toe link and adjusted the others to get a half decent alignment to start with.
I did come across one measurement that looked out of place, the height of the attachment point of the strut piston, is about 5 inches lower then what is on your drawing. If I use your number, my strut does not have enough travel in droop. (Strut is model on a worn out Monroe unit)
As you can see the toe links are at an rising angle to start with, which takes away negative camber as the wheel moves up. For more negative camber gain, the toe links should be angled down at ride height.
It looks like the 3 inch addition acts pretty normal,
------------------ yellow 88 GT, not stock white 88 notchie, 4 banger
Bloozberry
MAR 22, 07:50 PM
I suspect there's something wrong with the numbers you've used on one of the animations since there should be no difference in the angle of the toe links if the only variable was their length. Did you change tire diameters between the first and second animation? Or change the ride height? Stock ride height IIRC is 6" (plus or minus) as taken at the bottom edge of the cradle. I'm curious why the height of the strut to mount is so much further off too. Must be something we're missing.
ccfiero350
MAR 22, 08:54 PM
Oh yes, there could be a lot of differences, one of them that crops up is all the links must be constrained as ball joints, and locating the pivot point in a rubber bushing adds a certain amount of guessing, but your right, theoretically the links should be parallel, in real life I've seen them a little like the animation. As for the strut location, what do you measure in a strait line from the center of the hole in the strut tower to the axis of the front toe link on the sub frame? I can match that and try again.
I been using the 5.75" as a chassis height because that was what it was before I took the car apart. I'm not sure if in the real world the bottom surface of the sub frame is actually parrallel to the the ground, isn't there a bit of a rake?
I did change the wheel/tire, the first one was 17x10.5 with a 285/40.
------------------ yellow 88 GT, not stock white 88 notchie, 4 banger
Bloozberry
MAR 23, 08:17 AM
The distance from the inboard axis of the lateral links to the center of the top strut bushing (which is the effective upper pivot point of the strut), as viewed from the rear of the cradle in a straight line, is 1275 mm (50.2"). You shouldn't use the hole in the strut tower since the bushing is further down by an inch or two.
The cradle bottom, at stock ride height is parallel to the ground... no rake fore or aft.
Tinkrr
MAR 23, 08:47 AM
By grabing the cursor and slowing down the animation it appears to me in both the side view and the lateral view, that the axle will interfere with the engine cradle when the suspension is in full droop
Bloozberry
MAR 23, 11:15 AM
It's just the angle the drawings are seen from. You have to keep in mind that on the driver's side, the inboard end of the axle (where it crosses over the dradle side rail) is kept away from the cradle by the CV joint being mounted a fixed distance away from the cradle. The joint allows the outboard end of the axle to droop below the cradle as seen from the side view, but the outboard end of the axle is much further away from the cradle.
On the passenger side, the long axle does get closer to the cradle because the CV joint is much further inboard so there's more relative movement between the axle and the cradle where the axle crosses over the cradle side rail. But again, it clears in the stock configuration and longer lateral links will only improve upon this clearance. In my case, I'm also using a jackshaft to move the passenger side CV joint outboard.
DeLorean00
MAR 23, 05:27 PM
Whoa whoa whoa!!! There is way too much engineering going on in here. This is a kit car. All you need to know is how to mix bondo and how to use sheet metal screws.
lol
ccfiero350
MAR 24, 08:15 AM
I'm going to throw an axle and sway bar on it too to see how whole ball-o-wax looks. What is the length of your new longer trailing arm?
------------------ yellow 88 GT, not stock white 88 notchie, 4 banger
ccfiero350
MAR 24, 11:51 AM
We have discrepancy in dims. I've set the upper strut pivot point (red donut) at 50.2" The shown dim is the from the upper strut pivot to the center of the front lower link hole. I may be wrong, but I don't think the top of the strut is two wheel diameters off the ground.
------------------ yellow 88 GT, not stock white 88 notchie, 4 banger
