A bunch o Q:s from a new owner

[ajaxajax2000]

Ok, I had the car (’92 ZR-1) for a week now and a number of questions are piling up. :confused: :confused: Hoping you can dig into your vast experience and help a rookie out:

1 The car has been considerably lowered which makes it hard to drive on regular Swedish roads. Can someone on a step-by-step basis please explain how to get it back to stock height? (Or advice a link). With the car came (a loose) what I believe is the original spring (black glassfibre blade – front or rear?) This is my first Vette so please explain in the simpliest way possible. :redface:

2 Ride control. Changing from Tour to Sport to Performance doesn’t seem to make any difference. How big is the ride quality difference? Should I notice it beyond any doubt? I’m not having any warnings on the Info Center. What could be wrong if it doesn’t work? In fact – the car is so hard on the road it feels as if it has no suspension at all! Any connection to the car being lowered?

3 Service LTPWS comes on after some half hour ride and goes out again when engine is stopped. Why? What to do? What kind of service? The tire pressure seems ok. I’m about to change wheels/tires. Should I skip the LTPWS sensors on my new wheels? How would the car react to that? (I’ve understood that the sensors can be a real danger if they come loose at high speeds)

4 I’ve spotted a rather deep dent in the left exhaust tube just where it bends outwards in front of the rear axle. Looks like a bottle neck performance wise. System otherwise in good condition. Any hints on how to get this dent out again?


Enough with the whining – the car is just awesome to drive, beautiful to look at and has the sexiest sound (competing pretty successfully with the purr of my wife)! I’m in love... :mrgreen:


Most greatful for any tips on my technical questions. :worship:

Peter

PS, I’ve been trying to search the forum for answers, but the search functions seem dead to me ..... :sleepy1:

[guinnessdood]

Ok, I had the car (’92 ZR-1) for a week now and a number of questions are piling up. :confused: :confused: Hoping you can dig into your vast experience and help a rookie out:

1 The car has been considerably lowered which makes it hard to drive on regular Swedish roads. Can someone on a step-by-step basis please explain how to get it back to stock height? (Or advice a link). With the car came (a loose) what I believe is the original spring (black glassfibre blade – front or rear?) This is my first Vette so please explain in the simpliest way possible. :redface:

2 Ride control. Changing from Tour to Sport to Performance doesn’t seem to make any difference. How big is the ride quality difference? Should I notice it beyond any doubt? I’m not having any warnings on the Info Center. What could be wrong if it doesn’t work? In fact – the car is so hard on the road it feels as if it has no suspension at all! Any connection to the car being lowered?

3 Service LTPWS comes on after some half hour ride and goes out again when engine is stopped. Why? What to do? What kind of service? The tire pressure seems ok. I’m about to change wheels/tires. Should I skip the LTPWS sensors on my new wheels? How would the car react to that? (I’ve understood that the sensors can be a real danger if they come loose at high speeds)

4 I’ve spotted a rather deep dent in the left exhaust tube just where it bends outwards in front of the rear axle. Looks like a bottle neck performance wise. System otherwise in good condition. Any hints on how to get this dent out again?


Enough with the whining – the car is just awesome to drive, beautiful to look at and has the sexiest sound (competing pretty successfully with the purr of my wife)! I’m in love... :mrgreen:


Most greatful for any tips on my technical questions. :worship:

Peter

PS, I’ve been trying to search the forum for answers, but the search functions seem dead to me ..... :sleepy1:

Can someone on a step-by-step basis please explain how to get it back to stock height? (Or advice a link). With the car came (a loose) what I believe is the original spring (black glassfibre blade – front or rear?) This is my first Vette so please explain in the simpliest way possible.

Does the car now have Coil over shocks now? It sounds like it has coil overs. If that is the case...they can be adjusted quite a bit to change your ride height and ride quality. if you want to remove the coil overs (or the non-stock spring...the rear is easy to remove and replace...just loosen the bolts slowly with the weight off of the wheels. The front is more difficult. You need to get a Factory Service Manual for starters anyway. (http://www.helminc.com/helm/Result.asp?Style=&Mfg=GMC&Make=CHV&Model=CVET&Year=1992&Category=&Keyword=&Module=&mscsid=PPUEUN3WABTF9PF33PVA2RP3RGJ865Q6)


Ride control. Changing from Tour to Sport to Performance doesn’t seem to make any difference. How big is the ride quality difference? Should I notice it beyond any doubt? I’m not having any warnings on the Info Center. What could be wrong if it doesn’t work? In fact – the car is so hard on the road it feels as if it has no suspension at all! Any connection to the car being lowered?

The ride quality difference is pretty slight but over time you will notice the difference. If you have coil overs...the differenc emay be hard to tell if it is set up really stiff. The light bulb could also be blown. Does the light come on when you turn the key on?

Service LTPWS comes on after some half hour ride and goes out again when engine is stopped. Why? What to do? What kind of service? The tire pressure seems ok. I’m about to change wheels/tires. Should I skip the LTPWS sensors on my new wheels? How would the car react to that? (I’ve understood that the sensors can be a real danger if they come loose at high speeds)

A lot of people have removed the system from their cars. This is probably a good idea if you do some high speed driving (140+). I have removed mine for fear of the band breaking at high speed and loosing control of the car. I have had one come loose at like 90 MPH....not pleasant. I know of someone else that lost one at ~150....not nice. If the light bothers you....remove the bulb for the LTPWS.

I’ve spotted a rather deep dent in the left exhaust tube just where it bends outwards in front of the rear axle. Looks like a bottle neck performance wise. System otherwise in good condition. Any hints on how to get this dent out again?

No idea how to get the dent out again...except by replacing the stock exhaust with an aftermarket one or by cutting the pipe and welding in a new piece. I would opt for the aftermarket exhaust and of course headers...and aftermarket cats if you need them. Great modification!

Best of luck with your newfound pleasure in the ZR-1...Long live the BEAST!

Uly

[ajaxajax2000]

Thank's for the exhaustive answer Uly. Could you just explain "coil over shocks". Does it mean coil springs around the shocks? Cause in that case the answer is no. The shocks have no coils around them, not front, nor rear.

Peter

[guinnessdood]

Thank's for the exhaustive answer Uly. Could you just explain "coil over shocks". Does it mean coil springs around the shocks? Cause in that case the answer is no. The shocks have no coils around them, not front, nor rear.

Peter
Peter,

That's correct. The shocks would have coils around them. You can definitely do the rear spring by yourself...but the front is a bigger job. It is best done using a service manual.
Here's a couple of links that will help.

http://corvetteforum.com/techtips/viewsubtopic.php?SubTopicID=138&TopicID=2

http://corvetteforum.com/techtips/viewsubtopic.php?SubTopicID=194&TopicID=2

Uly

[ajaxajax2000]

Thank's again Uly. I'll study the articles and I already ordered the manual you linked me to.:thumbsup:

Peter

[Tom]

2. Ride Control: This is my opinion based on my 90. The difference between the three settings is very noticeable on rougher roads like I typically drive on here in Southern California. There is a substantial difference in the ride quality and how far the car moves up and down over some of the dips and bumps. The car seems to float and move substantially more in the touring setting while the car moves very little in the performance setting. While in the touring setting it is even easy to notice the change in ride quality when the computer changes the shock setting between 60 and 70 mph when driving on the rough freeways here. I very rarely use anything other than the touring setting here because most of the roads are so rough.

On good smooth roads the difference between the three settings is much less noticeable but you can still tell the difference over larger undulations in the road and when cornering.

[ajaxajax2000]

Hmm... Sounds like mine needs a check. Most bigger roads in Sweden are pretty decent, but when I pass some sharp bump (like entering a bridge slightly higher than the road surface) there is a violent shock through the car. Like it had no shocks or suspensions at all. :mad: There seem to be no difference whichever ride control setting I use.

I guess I'll start with checking if the warning light is ok and work my way from there.

Peter

[Tom]

Depending on your definition of a violent shock, you will definitely a sharp jolt from sharp bumps when the shocks are in the performance setting.

Also, you can look at the front shocks and make sure the actuators that change the shock setting are still on the top of the shocks and are still connected to the shock and the wire harness is still plugged in.

[ajaxajax2000]

From the quick looks I've made everything seems to be in place. Is there any checks I can do to see if the ride control is active? Any current to measure somewhere or can I feel any reactions in the shocks or hoses when I change the settings (when the car is standing still, of course)? How do these suckers operate anyway? Some kind of valve setting changing or what? :confused: :confused:

Peter

[Tom]

The shop manual has an explanation of how the system works. Error codes are set when the system malfunctions. The shop manual tells how to read the codes and has several trouble shooting trees to determine the causes of the various codes.

The shock damping is changed by the actuators on top the shocks rotating a shaft that changes the size of the damping orifices.

I believe the "Svc Ride Control" light should illuminate for a short time when you turn the key on which should tell you whether the light is good and the Ride Control computer is working. Also three key on-off cycles without starting and driving the car will set an error code and illuminate the "Svc Ride Control" light until the car is driven which will turn the light off but leave the error code.

You stated your car was lowered, is it lowered so far that you are constantly hitting the bump stops? This will make the car ride rough.
You see this a lot in Southern California, mostly modified import cars. I once bought a Roadrunner that had the front end lowered enought to constantly hit the bumpstops and it rode pretty rough, but it was easy to raise the ride height enough to keep it off the bumpstops since they have a torsion bar front end and you only have to turn a couple of large bolts to vary the front ride height.

Also since you recently bought the car, did the prior owner have the shocks rebuilt and revalved to make them stiffer, did he install a ride control computer with a different program that keeps the shocks stiffer? I believe if you look at some of the tech info on this website it talks about having the shocks rebuilt and the different ride control computers.

[ajaxajax2000]

"Also three key on-off cycles without starting and driving the car will set an error code and illuminate the "Svc Ride Control" light until the car is driven which will turn the light off but leave the error code". Tried this without any respons. In fact the Svc Ride Ctrl light is totally dead, which may indicate the bulb to start with.

Got the manual today. It looks very complete. some 3+ inches thick! :icon_scra I'll study that before I harass you guys with more questions. I'll also have a word with the owner who lowered the car.

Plan is to restore the ride height to original during this winter and get the ride control in order at the same time.

Thank's for all help :thumbsup:

Peter