Hi mqqn,

Your Z looks f-ing great with the 505's!

Can you PM me with the specs on your wheel/tire choice?

Thanks!

 

Hi Jay -

thanks! Pm sent.

best regards -

mqqn

 

NOT a smart azz question at all, but if a coil over set up is the best way to go, why do they design and build the cars with the stock set up the way it is?

MD

 

Do not remove and toss your air dam. It plays a vital role in getting air to your radiator............

 

I don't know the answer, but I would imagine that cost played a big factor in GM using the leaf spring design for the car.

 

Yes for high speed driving (let's say 100mph+). You need a minimum of 1/2" rake, but preferably closer to 3/4". Measured under the frame (not the body panels). Before and aft of where the jacking locations are. If you're not a road racer you can ignore. Just note incase you get a wild hair to run it up to 120-140mph or so that the front end starts to lift and the steering will lighten up. No it won't flip over like a sail plain but it is not stable.

 

I agree. The engineers jobs are to design it as best as possible. Then product mgrs and bean counters jump in and show them their budget. They make trade-offs and concessions.

There is also another design rule at GM that the engineers must follow. It's called NVH. Noise, Vibration, Harshness. A couple of good examples. Putting a CAI and headers on any LSx engine really wakes them up. $ for $ the best bang for the buck without tearing into the engine. Problem is opening up the breather increases valve train noise and exhaust droan. Doesn't pass the test. Headers obviously make it louder. That's why they have the GM High Performance Division to sell us gear heads on all the fun bolt-ons. They know we don't care about NVH, just HP/TQ

The suspension is the same idea. Want it tighter. Get the T1 setup from GM High Perf. Coil overs takes it to another level. I'm interested in getting some real results from the coil overs that Aaron made. They look like a good design and the price is attractive. The biggest question I ask myself. Are you really capable of getting all you can out of the car on track just the way it sits today (driving skill)? My answer so far is no.

Graham

 

For those that may be interested, I am going to try and put together a group buy on the Pfadt coilovers in the near future.....

 

Not a bad question at all. As a former engineer at both GM and DaimlerChrysler, I can tell you that there are a ton of reasons for why cars have the compromises they do.

In regard to the Corvette leaf setup, I would say that cost and weight are the two main drivers. It is hard to beat the weight of the leaf. With coil-overs it is about a wash weight wise. If someone built a set with full aluminumm bodies, they would probably weight less than the factory stuff, but would be very spendy.

Many people will tell you, and I would even agree, that there is nothing inherently wrong with a leaf setup on the Corvette. The FE4 suspension package happens to be very nice in my opinion. The 'cross talk' issue has good and bad elements to it. Overall, the leaf setup functions well as designed, but lacks adequate adjustment.

The factory suspension is saddled with a couple of limitations. One, it is difficult to adjust ride height. You need different bolts and cut bushings etc which leads to corner weights that are way out and a front you can't get low enough and so on. The second problem is that our government's impact standards require high bumper heights to pass. The Corvette like many of the European cars sold in the US have a ride height above what most would consider ideal for either aesthetics or performance. That leads to the problem that if you lower the car the suspension doesn't work there. The shocks bottom out, the leaf spring rate is not high enough to absorb large bumps with the limited travel and the car gets harsh.

A nice solution to the limitations of the OE setup is coil-overs. There are other solutions that can work as well.

ciao,
Aaron

 

Thank you for the detailed explanation.

OK. So now I know why. I think the next reaction of the prospective coil-over customer would be fear that they would not know how to set up the car. How can someone with absolutely no suspension set-up knowledge or experience dial in these "infinitely" adjustable dampers...

For example, I do trackdays at Sebring (bumpy and medium to high speed turns). From what I understand Coil-overs are a step above. But I also understand that a suspension that is not set up correctly can make a car's behavior at best erratic and at worst dangerous. How does the beginner get over this hurdle?

Thanks,
MD

 

MD,

The adjustment that these coil-overs have certainly can seem daunting. The botttom line is that there are two things you will really play with. The first is ride height. There is a sweet spot within the range that will give maximum performance, but mostly it is a matter of personal taste. I would say that this adjustment is driven by aesthetics.

The second adjustment is the damping of the shocks themselves. Some people would argue that if there are 16 settings, 15 of them are wrong. For maximum performance, given your particular car, there will be an optimum setting. I start all of my setups with the middle setting. The optimum setting should be close to the middle for most Corvettes. However, many customers find that the adjustable damping is also a great benefit on the street. They will use a lower setting for street driving to keep the ride softer and adjust accordingly for a spirited drive or track event. The adjustment is easy enough to run a session and make an adjustment and then compare the feel (or even lap times).

Our system is designed to work well out of the box. Any tuning that you would need to do is to match your taste and the specific driving you will be doing that day. The reality is that our customers generally adjust them for a couple of weeks and then settle in on one or two setups that work to suit their needs.

Our instructions include a guide to the setup and we are available on our 800 number 5 days a week (usually more by e-mail) to help with any specific questions.

-Aaron

 

Well now I'm actually tempted to get them Damn you and your great explanations

MD

 

That's why his coilovers are my next mod. Threaded bodies are the best imo, no messing with pre-load, shock travel, ride quality, etc Every car I've owned in the past 6 years or so has had coilovers, i'll never go back!

 

Since you have lowered your car,Is it more difficult to use the ramps to change oil ?

ns3

 

I built my own ramps from wood from Home depot into three inrimental steps up so that I could put the car on jackstands...worked like a charm for an $10 investment.