drmiller100

I weighed the 350 ready to go back in. engine is complete with turbo 350 tranny. Has oil, but no water. 680 pounds. Is the air compressor 30 pounds? In any case, it looks like 100 pounds gain going to a v8 over factory engine.

Lets say I put suspension limiters on the front suspension. So you get in a left hand corner, and the left front limiter gets tight. So now you go faster, and the whole chassis leans even more. What keeps the left front tire on the ground?

Ok, will you agree the zx also has pro squat under acceleration????

Wow. So what is your logic??? The car has different transfer at different speeds???

ummm, the springs push UPWARDS. Those braces in the engine compartment aren't going to do much to stop the strut towers from continuing.

what he said. i'd probably do option 2 because i am lazy and wouldn't have to grind the weld down.

I did a roll bar. Main hoop looks just like yours, tied to same place, except I went 12 inches wide on the base plate, and wrapped down over the front. Then I Went back to the tops of the strut towers, then welded a cross bar straight between the strut towers. Part of the goal is to locate the tops of the strut towers. They are THE main suspension loading point in the back half of the car.

mount the seats. then put carpet around them.

that's funny...... I was assuming you already had a bushing kit and didn't like the squeaky's....... grease the bushings up when you put them in. i can't remember which one i had, but i think they are all about the same.

Lets say we have power induced antisquat. That means we probably have brake induced antilift. When we stab the brakes, the rear brakes pick the rear tires up off the ground, causing you to spin out. It is pretty easy to design a suspension with zero toe, that still has plenty of roll steer. The ZX is one of them. If a car tends to nosedive under braking, then you might consider antidive in the front. When all done, if you don't have enough horsepower to roast the tires on corner exit, you probably don't need antisquat. However, on autocross and circle track with big horsepower, I think there is a place for it. I know my IMCA modified had a bunch of antisquat and floater brakes, and it was pretty old school 8 years ago.

if they return to the tops by themselves they are still charged, and are probably fine.

like he said, it is usually the trailing arm bushings. To confirm, you can squirt them heavily with wd40 and drive it around the block right away to see if it gets better. also, is it quieter on rainy days???

Roll over protection and side impact are why you are "supposed" to have cages. Real world says you can stiffen the car at the same time. It seems to me the real goal when stiffening the car is to allow the suspension to work correctly. And, the thing the car needs the most help with is Twist between the upper strut towers, front and back. And, it seems to me the hardest one to stiffen is probably the tops of the front strut towers. So how do you guys tie the top of the front strut tower to the top of the back strut tower?

If a rear suspension has antisquat, the rear suspension will probably have pro squat when braking, which is a bad thing. However, the antisquat in and of itself generally outweighs braking issues. One thing circle track guys do is put the calipers on bearings, and run a separate rod to the chassis to get "pro lift" on braking, and "prolift/antisquat" under acceleration with the 4 link. It is really hard to get antisquat on a rear wheel drive without affecting the rear axle steering in a negative way. In a perfect world, the rear axle would turn the rear tires in the same direction as the front tires for fast transitions and good exit speed. When you go antisquat, the rear tires probably steer opposite the front, which causes slower transition. The vette pics are great.

see the sticky at the top of this list.

i think the only thing you wouldn't want in there would be rocks, and I don't know how you would keep rocks out.

car is pretty well stripped down, started painting the interior. weighed what is left. Right about 900 pounds. This is bare chassis, but with dash, stuff under the dash, steering rack and steering wheel, rear R180, both halfshafts, and stock driveline. No hood, but did have rear hatch. No glass, doors stripped but on, interior completely gutted. Btw, the 580 engine weight I listed above included factory 4 speed tranny.

Lets talk about Antisquat and Antidive. Antisquat is also known as Pro Lift. Antidive is talking about what happens when you apply the brakes. If you design the suspension in a specific way, the brake torque or forces are directed to Lift that end of the suspension. Here is a side view of Anti-dive. The car is heading left, assume the brakes are on. And it is an SLA suspension, unlike our struts. http://www.tonyfoale.com/Articles/Dive/Dive_5.gif The forces MUST go up the arms. Depending on how the arms are positioned, the chassis could be "lifted", neutral, or "sucked down." There is an excellent writeup here: http://www.tonyfoale.com/Articles/Dive/DIVE.htm I'm having a tough time finding a good pic of antisquat. The drag racers call it changing the instant center, which is indeed a better way to describe it. Milliken has a terse description of it in their pamphlet. I found this, which maybe gives the idea with a live axle. http://www.wallaceracing.com/coilspring.htm Basically, you are using the forces to LIFT the back of the car on acceleration. The drag racers and oval track racers use it to get "bite" on acceleration. The traction advantage only occurs while changes in torque are occuring. So, when you hit the throttle, you get a moment of "bite" before the forces all level out. But that moment can be HUGE on getting the jump on your competitor!!! To summarize for z-cars, I don't know how to get antisquat on a zcar, and antidive isn't worth the effort.

I'll start a new thread......:wink::wink:

what do you think bump steer spacers do????

Actually, No. Anti dive is caused by the BRAKES and suspension transfering a force into the chassis to lift the chassis. A great example is an old fashioned VW bug front axle. If you hit the front brakes, the torque of the brakes actually try to pull the front of the car down. They have "pro dive." If we were going really fast in a VW Bug backwards, and slammed on the brakes, you can visualize the torque of the brakes lifting the front of the car in addition to the weight transfer. Anyway, we can all agree the so called bump steer spacers don't do anything???

If everything works, and you have no air, then why do your brakes suck???? Does your master cylinder pump fluid in the first 1/3 inch of travel?

well, not really. Antidive is using the force of the brakes to "lift" the front of the car. Done correctly it can increase instantaneous braking force, reduce pitch.

what most of us do is run too much static camber in order to have the right camber in a corner. So how do we get antisquat on a 240z????

if you have power induced UNDERSTEER, you are not on the gas nearly hard enough. Power induced understeer is when you are in the middle of a tight sweeper, and you kind of tickle the throttle and ask it nicely to gently speed up. For autocross, late apex is almost always fastest, and in that case you get on the gas so hard you are worried about the back of the car spinning out, and are desperate to feed it more throttle. If you are waiting until later in the corner to brake, turn, and turn, you are early apexing and going slow. The whole point to running a LSD/Spool is to brake earlier, turn earlier, and make the NEXT straightaway even longer under WFO throttle.