42Chevy

This question is for those of you that have lowered your base C6 using the factory screws. Does the car handle differently? Shudder when hitting a bump? Any drawbacks I should be aware of before I do it? The last thing I want to do is drop it so it looks better and destroy the handling aspects of the car. Your knowledge is appreciated.

LFZ

You will get a ton of responses all over the board on this....most will be inaccurate and silly; however having lowered many C6s on stock bolts including my own back in the day. You will see no harm in handling, no downgrade in performance, and if you needed an alignment, your car was probably off before you dropped it that 3/8-1/2". There is not enough drop on stock lowering stock bolts all the way up to cause any issues...that's what it's there for, but if you start cutting bushings, going with lowering bolts...that's a whole different arena.

CMY SIX

HE"S RIGHT! "inaccurate" Him too! for the 21,364 time the bolts you speak of are NOT "lowering bolts" they ARE "wedge bolts" which most cars don't have, and are used for setting the "wedge" of each car as each car built will have a different wedge, if you were to change springs or go to coil overs you would want to set the "wedge" also.

wayback

No issues at all for me. Did not need an alignment, had it checked to be safe. Funny thing is I have never needed an alignment even after 100,000+ miles.

Seems the shocks wear out a little quicker. On my 3rd set, but I replaced the stockers before they were shot.

LFZ

"Wedge". Like I said...silly.

Boomer111

This thread is full of wedgees.

truckplay

your best bet it to count the turns. I have heard that if you have F-55 suspension you should not cut the bushings because it takes the shock rebound out of it's damping range. This is what i did 3 years ago. you will have to wait about 1 week for the springs to settle and then have it aligned. be VERY CAREFUL until you learn how LOW the car is or you will cost yourself LOTTS of money

BEZ06

I like to use the correct terminology for stuff relating to our car, but I don't have any problem with using common terms of reference that we all know and understand - like "lowering bolts"!!

Butt.....if you're a stickler for the proper name of these bolts, it certainly isn't "wedge bolts"!!

Take a look at the picture below from my 2006 Service Manual. On the right side (p. 3-15) at the bottom of the left column in the "Important" paragraph, you can see what Chevy calls the bolt - the "spring adjuster bolt", because of course you can raise as well as lower the car by adjusting the bolt:




I like the term "lowering bolt" - we all know what is being talked about when using that term.

The "Z height" referred to is the front trim height, and the rear trim height is the "D height".


I had a 2005 with MSRC (my brother-in-law owns it now with about 60,000 miles on it). I lowered it and had NO problems at all. The front went down okay on the stock lowering bolts, but I cut the bushing on the rear bolts to get it where i wanted it. I didn't get an alignment (I do my own alignments, and I checked it and it didn't do much if anything to the alignment). It rode great on our smooth Florida roads, although it did several trips from Daytona up to New Jersey and Ohio. My b-in-law lives in NJ and has raised it slightly due to potholes, etc. up there. Here are some pics that sorta show how it looks lowered - the Z06 was up in Joisey at my sister's house visiting the '05!







As far as handling, racers like to lower the car to get the CG as low as possible. Of course they put on stuff like coilovers, drop spindles, solid bushings, aggressive camber, corner weighting, and a bunch of other suspension changes to make the car handle better.

However, overall I see no problem with dropping the car as low as you want it and your local potholes and speed bumps will allow.

Just MHO, YMMV!!

Bob

AddisonD

I think there is some split opinion on the virtues of fhis adjustment.
I'm in the group that does not agree that these cars look better lowered.

42Chevy

Well...It does not matter at this point. I give up. I did everything like I was supposed to. Got the weight off the bolt and could see a gap between the rubber and the control arm. Then proceeded to break 2 6 point snap-on sockets before the head rounded off. It will NOT break loose. I think its the cars way of telling me that the ride height is just fine.

BEZ06

The cars come with all different heights from the factory - the trim heights and alignments vary a great deal from car to car as they come off the assembly line.

My car looked friggin goofy as it came from the factory!!!!




Look at the gap between tire and fender!!! CRAZY!!!







I think it looked a LOT better lowered, and also with the Baer Eradispeed rotors (+2 on the rear) and body color calipers:




There are some mods I don't particularly care for, but if the owner likes it then its a good mod!!!

Bob

FlyerVette

Bob, Did you need an alignment after the lowering...??

BEZ06

No. I do my own alignments on my cars, so I checked it after lowering and nothing changed significantly - not enough to require me to do anything at all to it.

When I change camber on Z06 for R-compound tires for the track, the toe is changed significantly and requires an adjustment of the toe, both front and rear.

Bob

FlyerVette

Thanks Bob......much appreciated.

ProfessorDeath

I really don't mind the fender gap on mine. It seems reasonable to me, maybe the previous owner had it lowered a bit. Who knows?

NormWild

I just adjusted my left rear one week after having it aligned, took it back and even that slight adjustment threw it out the alignment. You are changing the camber when you adjust the lowering bolts so you MUST re-align it. The alignment on these cars is so sensitive that even the car with my weight in it changed the adjustments from in spec to out of spec. I ended up having it aligned with me in it using the Pfadt Street/track combo. Handling, steering response and feel were dramatically improved.

NormWild

You have to spray the bolts with penetrating oil every day and drive it for several days to get them to loosen up, especially if the car is driven in all weather conditions.

BEZ06

that the suspension deflection can change alignment - but my experience is that it's negligible.

The car is built to change camber with additional weight in the car - you, a passenger, downforce from aero, downforce from dips or banking, steering inputs, etc., etc., etc.

I lowered my old 2005 Coupe about 3/8" in front and 5/8" in the rear. The change in camber was about 0.1 to 0.2 degrees, and the change in toe was insignificant.

My Z06 is a street and track car. I used to run Hossiers on the track. I'd adjust camber and toe every time I swapped on the Hossiers or went back to street wheels/tires. I drive the car to events and pull a trailer with my track tires and a couple boxes of spares and tools. I got tired of doing alignments so often, so I just run street tires on the track now - the Michelin PSS and PSC are so good that I just don't need R-compounds to get great performance.

My street alignment is about -1.2° of camber and 0 toe up front, and in the rear I've got about -1° camber and 1/16" toe in (I think that's about 2°).

I adjusted camber by removing/replacing washers behind the dogbones that mount the upper A-arms to the frame (the Z06 and ZR1 have them front and rear - the other models only have them up front, so to adjust rear camber requires adjusting the eccentrics).

Each washer is not quite 1/2° of camber, so when I removed 3 up front it went to about -2.6°, and in the rear removing 2 washers gave me about -1.7°.

Changing camber changes toe pretty significantly, and I ran different toe on the street and track anyway - so I had to adjust toe every time I changed camber.

For the street I run 0 toe up front, and a total of 1/16" toe-in for the rear.

For the track I adjust it to a total toe of about 1/16" toe-out up front, and 1/8" toe-in for the rear.

After adjusting camber, I found turning a tie-rod adjuster 3 flats (half a turn) would change toe by about 1/16".

After adjusting to my track camber settings, I found I had to tighten (shorten) both the front and rear tie-rods/toe adjusters to get my track toe settings. I had to tighten the fronts 9 flats on each side, and in the rear I tightened them 4 flats on each side.

When going back to street alignment I put the washers back in and turned the toe adjusters the same amount in the opposite directions.

So....I've done a lot of checking of my alignments, and I didn't find that lowering the car slightly made any drastic changes to the alignment. The factory alignment specs are VERY broad anyway. If anybody is doing an alignment I strongly recommend going with Pfadt alignment specs for the type of driving you'll be doing. Just be aware that when Pfadt says "-1/8 inch toe" they are talking about toe-in (most alignment machines use the convention that a negative toe measurement is toe-out). Also, they recommend front toe-in even for aggressive track alignments, whereas many track hounds (me included) like a tad toe-out up front for a crisper turn-in when cornering.

Just MHO, YMMV!!

Bob

speedraider

yep, they do freeze up. 2 months ago, I took my car to the dealer and they replaced my front spring and it came with new adjusters. Thanks to GMPP warranty.

Woodstoc

As stated above, the "lowering bolts" are there to allow adjustment to variances in car buid, ect. I lowered mine and saw improved handling and response. The way I did mine was to measure all four corners, on a flat surface, put my 200lb butt in the car, had a buddy then measure all four corners, and adjusted down according. At the end, I was exactly the same across the front, and exactly the same across the back. Back was 1/2" higher than front with me in it. I didn't cut any bushings.

No change in alignment, car handles solid (for stock suspension), and it looks better.