HybridZ custom suspension design thread

[V8ZRACER260Z]

I used a C4 cradle assy for my front set up. I basically set it in place centered the cradle and adjusted my wheel base and built the frame to it. Running 10" wide original vette back space rims requires about a 3" flare to clear the tires. I chose this set up because of all the vette upgrades availible and it still uses factory component should something break I won't have to make a part, I can go to the dealer and buy a part of the shelf. Also since the contol arms and rack bolt to the cradle everything is in factory alignment. I measured the angle in the vette before removing the cradle to make sure. Doing this also makes the cradle removable for maintenance purposes. Hope this helps. Rick

[V8ZRACER260Z]

Forgot pic scroll down to outside front view

http://www.picturetrail.com/gallery/view?p=999&gid=630454&uid=481950

[Dragonfly]

Wow I like the way you think. That car is bad ass.

 

Dragonfly

[V8ZRACER260Z]

Thanks, The project it is taking a bit longer than anticipated but I'm on the downward side now. I'm hoping to be on the road in the next year or so.

[LLave]

This might be a stupid question but, is C4 vette suspension really all that much better then Z car? I mean strictly in terms of performance, cool factor aside, when they are both tuned properly, Does the C4 really out perform the Z?

[RTz]

...is C4 vette suspension really all that much better then Z car?

 

Great question! Unfortunately, you'll get all sorts of opinions.

 

Here's mine... in a word, yes.

 

First I think there is some importance in distinguishing a C4... there are two varying front suspensions... '84 through '87 and '88 through '96. Within those will be further arguments. Putting those aside...

 

Its not so much that a C4 is 'all that', but I think its reasonable to consider that there's ~15 years of technology difference (willfully acknowledging that technology is not always advancement).

 

In summary, the S30's front suspension is high on kingpin & scrub, low on caster, with no appreciable ackerman, and coupled with high unsprung weight. Thats not an insult... just contrary to modern beliefs.

 

There are a few members here that will argue either side with more savvy than I, but the point remains... The C4 front suspension leans more in the direction of improvement than not.

[tube80z]

There's a group of us that are racing in XP, which has basically turned into our own little rivalry between a 89 vette and the rest of the Zs. If I look at the vette in pictures you can see the suspension on it does a much better job of keeping the tires flat to the ground. Currently the vette is quicker but if I look back at times against my old car they are closely matched. So like many things there are other variables at play that make a direct comparison difficult.

 

I had the opportunity to race a 510 on struts and then run the same car converted to double a-arms. What I mostly noticed was the car had much better steering feel. The odd thing was that it didn't have a lot better front grip. It was very similar to the lexus setup discussed in a different thread.

 

As Ron points out above the Z has a lot of SIA and this is what I think is more of an issue than the scrub. If you look at the tire contact patch you'll see the SIA has a tendency to roll it from edge to edge. There are a number of other effects too but I wonder if that is one that causes the front end to be harder on tires.

 

My gut feel is that double a-arms will better for a car that's going to do much longer runs on the tires. I also think it's better under brakes especially if you are generating large longitudinal loads. I asked a similar question in the motec seminar because I knew they had experience with the V8 supercars and got a more thorough but similar reply.

 

Cary

[zredbaron]

Great thread!

 

V8RACER260Z, very nice project putting in the C4 suspension! Ever finish the project?

 

...I have the shell of a 94 RX-7 cut up and will eventually be grafted beneath my old 73, (no, not the "super datsun" as that is a '72). A-arm front suspension, multi link rear, very light, proven, lots of aftermarket support.

-Bob

 

Bob, do you have any pics of this shell? Did you ever finish the project?

 

I'm one of the "just buy the kit" types (vice designing and fabricating it myself), also running XP.... JohnC, time to fabricate an all-out setup meeting your list of requirements!

 

Oh, and if you can make it anywhere as light as your Ultra-Light Racing Suspension, I'll be the first to pre-order!

Edited March 23, 2011 by zredbaron

[Sean111]

I have the front and rear subframes from a C5 vette sitting under my 240Z right now.......trying to figure out a way to make it work. I think it's going to require more expertise and talent than what I currently have.

[Aaj2k5]

Thought I would share what I'm doing for custom setup.

 

R34 GTR Rear Subframe, double wishbone, S13 coilovers bolt on, and with modified camber plates, are proper length. Requires a fair bit of modification to mount to chassis (Add in rear mount bar, two forward mounts, remove factory moustache studs) but fits quite perfectly.

 

S14 Front Subframe, S13 Coilovers, S14 TC Brackets and buckets. The subframe mounting holes are 1/2" wider track and require a bit of mod to bolt into chassis but it does bolt onto stock frame rails. Rear-steer using S14 Steering Rack, S14 Knuckles, S14 LCA, S14 Swaybar bolts into the S14 TC Brackets and the S14 Control arms.

 

Modern suspension, easily accesible parts.

 

"Project Gaizen" I think it was called also did the same setup I'm doing but he did RB26 setup, I'm KA-T. I also debated doing FC TurboII Front and Rear Suspension as the front subframe would have worked for my KA-T motor mounts, and have excellent suspension characteristics, but the deal fell through.

Edited June 15, 2011 by Aaj2k5

[jhm]

Come on, Mark....keep up, man!!