A&Q about 350Z
Q:
UncleBob,
I guess I will "figure it out, soon enough", as soon as I buy the transaxle, and build the frame, and start driving it!
Like I said, I just want to build it, and drive it! I'm not trying to win an Engineering Award, and I'm not building it to compete with a Lamborghini or Ferrari, either. I just want to build my own car, using parts that I already have, and don't have to find or buy (except for the transaxle).
Again, I never said I "had" to use straight axles, I said I'd "prefer" to use them, so I could fit the larger RWD wheels, instead of the smaller FWD wheels!
Thank you for helping me remember, because now that I think about it, the guy who built the other vehicle just used the original axles from the RWD, and had them shortened and resplined, so they replaced the CVs in the FWD transaxle! That was how he did it, and that's what I was trying to remember as part of the answer I was looking for!
Now, if I can just remember what I read about how he did the suspension for it, or I'll have to find the article about it, again...
However I build it, I just know that a midengine big block, rear transaxle, rear wheel drive, 1 or 2 seat, open frame type vehicle is going to be fast enough to have fun with, anyway! I don't care about debating the details of the engineering, I just want it sitting in my driveway, ready to drive, just to take it out for some high speed blasts on the highway once in a while!
A:
Buddy, we're trying to help you. No one has said that its not feasible to use straight axles, but every single one of us said it has some severe issues. From your responses, I don't think you understand what we are even saying.
No, you don't have to be a master engineer to do these kinds of projects, but you should at least study the disadvantages before you set your heart on doing it a certain way. You keep saying "someone has done it before"....I have no doubt on that. That doesn't mean its a good idea!
So again, how exactly are you going to work the rear suspension? Do you even have a plan? Aren't you interested in having ANY rear suspension? Ever ridden a car with no suspension? Trust me, its a TREAT!
A:
I know you're trying to help, and I appreciate it, I do!
Basically, I'm just trying to remember the details of what I saw for the other guy's vehicle, about what type of suspension that HE used!
Even from this discussion, you just helped me remember that he removed the original axles from the RWD diff, sent them to Currie Enterprises (differential specialists), who shortened them and resplined them to fit into the FWD transaxle, so he could use the RWD wheels with the larger bolt patterns, instead of the FWD wheels. That's how he was using the straight axles, that I was trying to explain, but maybe just didn't explain clearly enough, because I couldn't remember the details.
I do understand everything that we've discussed here, with no confusion, as I'm familiar with the different suspension systems, as I've either seen, or worked on, most of them used in factory cars, Hot Rods, Musclecars, Street Machines, Exotic Cars, and as many other vehicles that I've studied, researched, driven, and enjoyed.
I've only seen the one type of system that I'm trying to use, with available GM parts, without having to overengineer or completely fabricate something that would be impractical to maintain or repair.
To answer your questions:
I don't know how I'm going to do the rear suspension, because I don't remember how the one was built, as I saw it. That's been my question all along, is HOW did he do it? It could have been that the engine and transaxle might have been in some type of subframe, that allowed the suspension to be functional, by having a pivot point on the frame, if I remember, too.
My plan, currently, is to attach the engine that I already have built and ready to use, to the transaxle that I'll be using, and build the frame around it, using the suspension that it already has, until I can learn from my first vehicle how to improve or change it for the next one.
Yes, I am planning on having a rear suspension, but I'm trying to keep it as a "performance" vehicle, at the same time, not just for a "comfortable" ride.
I'd like it to have a somewhat stiffer suspension, for better acceleration and handling, but not too stiff that it feels like a solid framed car with no shock absorbtion.
No, I never have ridden in a car with no suspension, but I'm not planning on it, either, and I'll take your word for it, and not find out for myself.
A:
Having the entire drive train pivot is almost as bad as no suspension. Thats what we're trying to tell you. The best suspension is when you have very low unsprung weight vs sprung weight. You're talking about an assembly that could be over 800 pounds being your unsprung rear suspension component. It will not handle at all, it will not react to bumps at all. It will not hook up at all.
There IS no other way to deal with this situation. Either there is no suspension, or you move the entire drive train. Thats it without CV's, or seperate the differential from the drive train.
If it were mine, I would simply shorten the CV axles out of the orginal setup. Its the exact same thing as shortening solid axles. You can make it any length you want, although if you make them too short, you will have to reduce your suspension travel to prevent from breaking the CV's due to the hard angle it would create.
A:
I understand that, too. That's what's making this a challenge, to build it completely from scratch, without having the experience of having already built one, and having to learn on the prototype.
It's nothing more than a garage experiment, really, just to see how it turns out, as a Frankenstein vehicle (pieced together from all the new old parts that have just been sitting for years, waiting for something to do with them.)
My only concern is using a 455 with such a weak transmission, that uses CV joints and small wheels, but I'm going to chance it, anyway, just to see if it will take abuse, and be able to transfer the torque to the ground.
If possible, I may not modify anything, at first, just to see how it's all going to go together, and drive. When I pick up the donor car for the transaxle, I may just install the 455 in it, and drive it that way, just to find out how it handles, to have something to compare to, after it's removed and replaced into the rear of the scratchbuilt vehicle.
Would you recommend that, as a good place to start?
A:
this is the bit I don't understand.
you appear to be saying that the rear suspension of a car is there for comfort, that it has no effects on performance and hence unneccesary at this point. The whole point of independent rear suspension set ups (of which no one has mentioned trailing arms for location yet...) is that it should afford you better tyre/road contact
i.e it improves performance.
in order to make it a better performance vehicle, you NEED to have a decent rear suspension set up.
A:
I think I'm on the right track, now, as I looked up Lamborghini rear suspension, which uses the same configuration that I'll be trying to build for this vehicle (Longitudinal engine mount, with rear transaxle).
It uses what they refer to as a "wishbone" suspension, which is similar to GM's upper and lower A-arms.
With so many aftermarket tubular A-arms available, I'm thinking Hotchkis Performance tubular A-arms, that would allowing adjustment and stability, by using the CV axles!
That way, the engine and transmission are mounted securely to the frame, in the rear. The only moving parts of the suspension would be the Control Arms, Springs/Shocks, CV axles, and Wheels, as it should be!
This sounds much better, and now that I've actually had something to reference to, I think it will help my build go much easier, with something to compare with!
See? Good things can come from discussion!
I think I'm more on the right track, now...
A:
A Fiero needs to have the body stretched behind the firewall to accomodate a longitudinal engine/clutch/gearbox package.
In other words, it won't fit with the stock body panels.
A:
I'm not using a Fiero, at all!
I'm only using the Fiero links as REFERENCE material!
I will be connecting a Buick 455, that I already have, to a GM TH325 transaxle, to find out what measurements that they have as a combined unit, and then build a full tube frame around it.
No clutch, it's an automatic transmission, with overdrive. More reliable, more consistent that way, in my opinion.
A:
Are you really this fucking stupid? Every person that has replied to this damn thread as told you to do that, you dont even fucking know what the differnt types of suspension are called. Now you say what everyone else has said and think your an expert? Now your on the right track? I dont even think your anywhere close to anything that resembles a track.
A:
Relax TSC, there is no need to lay into the kid.
Remember we were all young and niave once, I used to think a Holden Comadore was the worlds best car.
A:
....i'm not even going to ask whether he knows the slightest thing about suspension geometry and that it isn't as simple as saying "
oh darn it, I just did.
A:
And there you go.........satisfied?
A:
no..... i have this.... hollow feeling inside me now....
A:
That may be indigestion.