Should I lower on stock bolts?
08-09-2014, 08:41 AM
#1
Instructor
Thread Starter
Should I lower on stock bolts?
I have searched this forum and understand the method of how to lower the C5 on the stock bolts. My question is whether there is any adverse affects of doing so that would result in a reduction in handling or a safety concern. I seem to remember reading a post about how performance is degraded by lowering on the stock bolts and it can result in an unsafe condition. Maybe something about the shock travel, I just can't find the thread or any discussion about the performance aspects of the mod. I definitely remember reading a post about a forum member who lost his life when he hit a tree. Someone posted that he was lowered on stock bolts and that could have contributed to the accident.When I search I come up with a bunch of how to's but no much about whether to...
Is there another way to lower that I may be confusing with lowering on the stock bolts?
I would especially like to hear from anyone with track experience before and after lowering on the stock bolts.
Is there another way to lower that I may be confusing with lowering on the stock bolts?
I would especially like to hear from anyone with track experience before and after lowering on the stock bolts.
Last edited by Enrique797; 08-09-2014 at 11:07 AM.
08-09-2014, 01:19 PM
#2
Melting Slicks
Some of the concerns about lowering the ride height of the car is when:
1. Lowered different amounts side to side and front to rear
2. Lowered so much the shock absorbers cannot function properly and and the body hits the shock bumpers and the car becomes unstable in a turn or pothole or drop in pavement on one side
3. Rake (the relationship of the front axles of the car and the rear axles changes adversely. If the rear is lowered more than the front and the front end becomes higher, the vette turns from a sports car into a wing set for lift off. This was a problem with the C2 vettes because at about 130 mph you would louse feedback from the front axles.
4. From a handling perspective you can mess up the corner weights of the car and its handling. The vette might turn to the right very easily but fights you turning left or vice versa.
5. Most of the road irregularities like pot holes, speed bumps, driveway grades, etc cause scraping at the front spoilers.
If you are going to do it then get with someone who knows how to align a corvettes rake, corner weights and alignment. It is doable if you let the car down about 1/2 inch front and rear--equal number of turns on all the leaf spring bolts and then should have it realigned.
1. Lowered different amounts side to side and front to rear
2. Lowered so much the shock absorbers cannot function properly and and the body hits the shock bumpers and the car becomes unstable in a turn or pothole or drop in pavement on one side
3. Rake (the relationship of the front axles of the car and the rear axles changes adversely. If the rear is lowered more than the front and the front end becomes higher, the vette turns from a sports car into a wing set for lift off. This was a problem with the C2 vettes because at about 130 mph you would louse feedback from the front axles.
4. From a handling perspective you can mess up the corner weights of the car and its handling. The vette might turn to the right very easily but fights you turning left or vice versa.
5. Most of the road irregularities like pot holes, speed bumps, driveway grades, etc cause scraping at the front spoilers.
If you are going to do it then get with someone who knows how to align a corvettes rake, corner weights and alignment. It is doable if you let the car down about 1/2 inch front and rear--equal number of turns on all the leaf spring bolts and then should have it realigned.
08-09-2014, 05:28 PM
#3
Safety Car
Lowered on stock bolts over 10 years and no adverse effects on my 2001 with F45 . Autocrossed about 10 events a year. Combined with C6 Z51 sway bars and Nitto NT01 tires doing pretty good. Important to keep the rake; the front should be lower than the rears.
08-09-2014, 08:14 PM
#4
Instructor
Thread Starter
Some of the concerns about lowering the ride height of the car is when:
1. Lowered different amounts side to side and front to rear
-Understood, it seems the best way to prevent this would be to have the corner weights checked. Is turning all the bolts the same number of turns an acceptable alternative?
2. Lowered so much the shock absorbers cannot function properly and and the body hits the shock bumpers and the car becomes unstable in a turn or pothole or drop in pavement on one side
-I believe this is what I was reading about. How low would you have to lower the car for this to become an issue?
3. Rake (the relationship of the front axles of the car and the rear axles changes adversely. If the rear is lowered more than the front and the front end becomes higher, the vette turns from a sports car into a wing set for lift off. This was a problem with the C2 vettes because at about 130 mph you would louse feedback from the front axles.
Understood, same comment and question as number 1 above.
4. From a handling perspective you can mess up the corner weights of the car and its handling. The vette might turn to the right very easily but fights you turning left or vice versa.
Understood, same comment and question as number 1 above.
5. Most of the road irregularities like pot holes, speed bumps, driveway grades, etc cause scraping at the front spoilers.
-Understood
If you are going to do it then get with someone who knows how to align a corvettes rake, corner weights and alignment. It is doable if you let the car down about 1/2 inch front and rear--equal number of turns on all the leaf spring bolts and then should have it realigned.
-When I purchased this car I made a promise to myself that I would be the only one to work on it whenever possible. As such, I was planning to do most of the work myself. I've been turning wrenches for some time, including an enlistment in the airforce working on jets, so I feel confident in my ability to get it done.
I am the second owner of this car and I am quite confident that the prior owner did little more to the car than change the fluids. So, I feel pretty comfortable that the car is setup the way it came from the factory. I am planning on lowering it just a bit to close the gap on my new wheels, maybe half an inch. Can I lower each corner, being careful to count the turns, and maintain the current corner weights and rake? If so, wouldn't I be in the same position after lowering it as I am now? Given that this car is 12 years old should I have the should I have the corner weights and rake checked anyway? (I will be having the car aligned either way.)
That being said, I like the idea of having the setup checked out once I am done but I would probably wait until I replace the shocks and swaybars which won't be for a little while.
As always, any comments or questions are more than welcome.
1. Lowered different amounts side to side and front to rear
-Understood, it seems the best way to prevent this would be to have the corner weights checked. Is turning all the bolts the same number of turns an acceptable alternative?
2. Lowered so much the shock absorbers cannot function properly and and the body hits the shock bumpers and the car becomes unstable in a turn or pothole or drop in pavement on one side
-I believe this is what I was reading about. How low would you have to lower the car for this to become an issue?
3. Rake (the relationship of the front axles of the car and the rear axles changes adversely. If the rear is lowered more than the front and the front end becomes higher, the vette turns from a sports car into a wing set for lift off. This was a problem with the C2 vettes because at about 130 mph you would louse feedback from the front axles.
Understood, same comment and question as number 1 above.
4. From a handling perspective you can mess up the corner weights of the car and its handling. The vette might turn to the right very easily but fights you turning left or vice versa.
Understood, same comment and question as number 1 above.
5. Most of the road irregularities like pot holes, speed bumps, driveway grades, etc cause scraping at the front spoilers.
-Understood
If you are going to do it then get with someone who knows how to align a corvettes rake, corner weights and alignment. It is doable if you let the car down about 1/2 inch front and rear--equal number of turns on all the leaf spring bolts and then should have it realigned.
-When I purchased this car I made a promise to myself that I would be the only one to work on it whenever possible. As such, I was planning to do most of the work myself. I've been turning wrenches for some time, including an enlistment in the airforce working on jets, so I feel confident in my ability to get it done.
I am the second owner of this car and I am quite confident that the prior owner did little more to the car than change the fluids. So, I feel pretty comfortable that the car is setup the way it came from the factory. I am planning on lowering it just a bit to close the gap on my new wheels, maybe half an inch. Can I lower each corner, being careful to count the turns, and maintain the current corner weights and rake? If so, wouldn't I be in the same position after lowering it as I am now? Given that this car is 12 years old should I have the should I have the corner weights and rake checked anyway? (I will be having the car aligned either way.)
That being said, I like the idea of having the setup checked out once I am done but I would probably wait until I replace the shocks and swaybars which won't be for a little while.
As always, any comments or questions are more than welcome.
Last edited by Enrique797; 08-10-2014 at 09:37 AM.
08-09-2014, 08:16 PM
#5
Instructor
Thread Starter
Sweet, how low did you go?
08-10-2014, 04:40 PM
#6
Race Director
keeping your corner heights even is the hard part. "turns" do not lower the car even as i found out. as you bring the car down you'll need repeated measurements to make sure you #1 keep the rake right and #2 keep the corner height in line. i biased mine 1/16th of an inch on the drivers side
around 1/2" down will still provide compliance on the street and keep you fast. more than that will really slow you down and make the car unsettled on uneven terrain
around 1/2" down will still provide compliance on the street and keep you fast. more than that will really slow you down and make the car unsettled on uneven terrain
08-11-2014, 07:45 AM
#7
Platinum Supporting Dealership
I would go ahead and lower the car. Lots of members have with no ill effects. I seem to remember there being an article about recommending a 1/2" lower ride height for improved performance around the track.
08-11-2014, 03:22 PM
#8
Melting Slicks
The rake should be OK if each bolt is turned the same number of times, the lower you make the car, the more you should check the alignment. Corner weighting is more for maximum handling and is not that critical for you average driver. For DIY alignment, there are several articles in the Autocross/Road Racing section on doing it correctly. Most are done with simple tools (jack stands, string, level, etc.) and some include easy to use systems.
A friend of mine had a Z06 he lowered to the max and the car looked "mean" and the wheel wells looked full. When we autocrossed i beat him constantly in my FRC vette and he was alway looking for more power and add-ons. Finally he asked to align his vette and now he beats me regularly. As he now say "I didn't know what I didn't know"
A friend of mine had a Z06 he lowered to the max and the car looked "mean" and the wheel wells looked full. When we autocrossed i beat him constantly in my FRC vette and he was alway looking for more power and add-ons. Finally he asked to align his vette and now he beats me regularly. As he now say "I didn't know what I didn't know"
