I thought I would share these before/after photos.

Ride height from the dealer was extremely high - you can see its a pretty dramatic change.

Took all of 45 minutes.

 

Looks great. 45 minutes. What's the secret?

 

Thanks.

Jack it up - take the pressure off the spring - turn the bolts counter clockwise all the way out.

There is a really nice tutorial someone did that may really help you out.
Heres the link: Look Here

 

Looks great. I also have SG. I did my drop in 35 min...lol.

 

Looks great, alignment next?

 

You must have skipped the have a beer step.

 

Yeah I think so - next oil change - but it should still be within spec.

 

Good idea, I believe it's a complimentary alignment from GM.
I still have to lower mine.

 

I actually like it before the drop better.

 

non z07... thats why looks so dropped

what does it measure from ground to fenderlip all around?

 

You need after market rear bolts for the z07. They won't come down as much. Or you may be able to cut the grommet. I'll get some measurements later.

 

Not true. Ive lowered z07s locally including mine. Z07 will only go down to 28.25 rear ground to fenderlip Rear at most 1/2 inch stock bolts cut

My z07 with drop spindles 26.25 front and 27.25 rear ground to fenderlip

 

sweet

 

Thanks , doing it first thing tomorrow.

 

 

OK I was under the impression with aftermarket rear bolts for the Z07 package you were still getting 1" to 2" on the Z07 - I think I saw of yours with the drop spindles somewhere.

REAR from the ground to the top of the lip just about c hair under 28"
FRONT from the ground to the lower lip of the spat 26.75

 

If possible, have them do with your PDI<br/>If you already picked up your car<br/>As OP stated 45 minutes or less for this mod<br/>Looks great!! Is this the Shark Grey section?? Lol

 

Nobody seems to care about this, but I think you're being a little cavalier about the alignment. The C5 rear toe goes Toe-Out when lowering. Same with the C6. I would be surprised if the C7 doesn't do the same thing. If you drive with active handling (or whatever it's called now) on all the time, it may mask it, but the car is now very unstable.

Given how it has been demonstrated how sensitive the car is to alignment, I would check it.

 

I have to more or less disagree with your comments about stability - both from a drivers point of view and past and present engineering analysis and experience.

The fact of the matter is this: This height adjuster feature of this suspension layout, and a Corvette has one at each corner. Twirl all four and you can lower the car. Tweak selected ones while the car is sitting on a set of digital pad scales and you can "corner weight" the car to evenly distribute your own mass or optimize the car to suit whatever track or autocross course you might be tackling.

They are there for this purpose.

That statement above although paraphrased is from an engineering analysis done by Edmunds in 2014.

In addition SOME cars are requiring an alignment and some are not - those that have exhibited some alignment issues were more then likely off from the beginning, and there is NO consistency in how these cars are delivered to the dealer, I've seem them come off the truck looking like a 4 x 4 and others looking like the after photo I posted.

I'm wondering if your comments are based on direct experience and some engineering background or just something you may have heard in passing?

While there MAY be some concern about the hitting the bump stops on full load and there are many discussions on this based on some good engineering analysis as it relates to the motion ratios - the jury is out as to weather additional support is needed on a lowered or ride height adjusted car.

However I have seen no analysis or even any concerns about the stability of the automobile at speed or otherwise.

Please also consider MOST dealers in larger metropolitan areas WILL lower the car for you - at least this has been my experience - and from a liability view point I don't see them offering the service if indeed stability is effected.

I certainly appreciate your comments and if indeed there is some factual information out there concerning lowering C5's C6's and C7's on factory bolts can you please share it with the group?

Thanks ion advance.

 

This is from experience. I started doing my own alignments because you never know what you'll get from a commercial shop.

If you drive the car with the rear toed out the back end tends to wander. If you are cornering, as you try to feed power back in from the apex, the weighted tire (the outside rear, in this case) will try to increase the radius of the turn in comparison to the front because the thrust direction is to the outside of the turn, which will likely result in a spin.

I have experimented with a lot of unorthodox alignment specifications to see if I could improve lap times. I tried toe out at the rear and I gave up on that immediately as I found it to be undriveable. Some FWD cars do improve with rear toe out, so it was worth trying.

As for which cars will need alignment and which ones won't, it depends on how much the car is being lowered and where the other specifications were before you start. I don't think you would ever find a car that does the opposite, though. I'm just saying that, were it my car, I wouldn't be driving it for possibly weeks after doing this if for no other reason than the cost of rear tires.

I would really recommend that you check the alignment on your car shortly after purchase. I plan on trying to talk the dealer of my next purchase into doing that at a time of my choosing as a part of the deal. Most of the cars I have purchased from GM were out of spec in some way (including trucks), so, especially with the Vette, you're not getting full value for your money because the car doesn't handle the way it's intended to.