Need to Lower Rear Only by 1" after new Rims

[YELL03]

I installed 19x8.5 front and 19x10 rear Black AMR rims with stock size tires on my 2011 GT500 Convertible. They look great, but the rear tire to Fender gap is 3" and the front is 2".
I want to lower the rear only by 1" max.
I think the 2" gap in front looks perfect.
After hours of research I have found I can buy Rear Only Lowering Springs.
It seems H&R Rear Sport Springs would drop it 0.75 inch, this would probably be great, maintaining some rake, but closing the wheel gap.
Roush also makes a Rear Only Spring, but some people say it will be lower in the back than the front.

Also, with a mild 0.75" drop, will I definitely need an adjustable panhard, or should I install them and then see if it is necessary afterwards?

Have any of you tried doing the rear only?

Here are pics of how it sits now...

 

[im4darush]

I have an 11 coupe and looking to do same. Where can you get the H&R's in pairs?

 

[YELL03]

I have an 11 coupe and looking to do same. Where can you get the H&R's in pairs?

I think Van at Revan Racing can get them for you.
If not I found a non-forum vendor that can get them, but I will always try Revan first.

If Revan can't get them PM me

 

[Tob]

The aesthetic improvement from a more level ride height will definitely yield positive results in your case. If possible, you want to look for a spring that doesn't deviate a lot from the stock spring in terms of rate since it looks as though you aren't changing any of the dampers or the front springs. This will keep the suspension frequency in check, something you'd notice with a rear spring that was overly stiff/soft.

As far as the panhard bar...the amount of drop you are considering has almost no effect on lateral migration at static ride height. In other words, from a necessary functional perspective, an adjustable bar is not needed. That said, in keeping with aesthetic improvements, it would allow you to re-center your axle and thus provide for mirror-like clearances between each side of the rear axle.

 

[YELL03]

The aesthetic improvement from a more level ride height will definitely yield positive results in your case. If possible, you want to look for a spring that doesn't deviate a lot from the stock spring in terms of rate since it looks as though you aren't changing any of the dampers or the front springs. This will keep the suspension frequency in check, something you'd notice with a rear spring that was overly stiff/soft.

As far as the panhard bar...the amount of drop you are considering has almost no effect on lateral migration at static ride height. In other words, from a necessary functional perspective, an adjustable bar is not needed. That said, in keeping with aesthetic improvements, it would allow you to re-center your axle and thus provide for mirror-like clearances between each side of the rear axle.

This is exactly what I wanted to hear.
I will do the panhard later if it is necessary.
I will also stick as close to stock spring rate as possible.

 

[andymarkv]

I'm not sure on the newer cars.... But a lot of guys with 07-09 cars just used stock coupe rear springs to "level" their cars.

If you search around you should be able to find a few threads.

 

[YELL03]

I'm not sure on the newer cars.... But a lot of guys with 07-09 cars just used stock coupe rear springs to "level" their cars.

If you search around you should be able to find a few threads.

I've been searching for hours, it seems the H&R rear only or Roush Rear only are the best options.

The H&R are advertised as a 0.75 inch drop, might be a small enough drop to not need the adjustable panhard bar.

I like making as few changes to my car as possible.
My motto is KISS (keep it simple stupid)

When I did my TVS swap, all I did was change the TVS, kept the stock cai and TB, my car runs like stock, but with a heck of a lot more power.

Sometimes it works out, other times I have to do more, but the easier the better.

 

[YELL03]

I spoke to a rep at Roush and a Rep at Maximum Motorsports (H&R distributor).

Roush said if I use their rear springs that nothing else is needed, no adjustable panhard bar or anything else. Drop should be 1", no more.

The Rep at MM said the H&R drop is 0.75", maybe settle a little more than that, but not more than an 1". He said the adjustable panhard bar is not needed, but he recommended shorter rear bumpstops or the suspension will bottom out frequently.

 

[APMECH]

I spoke to a rep at Roush and a Rep at Maximum Motorsports (H&R distributor).

Roush said if I use their rear springs that nothing else is needed, no adjustable panhard bar or anything else. Drop should be 1", no more.

The Rep at MM said the H&R drop is 0.75", maybe settle a little more than that, but not more than an 1". He said the adjustable panhard bar is not needed, but he recommended shorter rear bumpstops or the suspension will bottom out frequently.

I've got those springs (H&R) and I did have to do a panhard bar. Panhard bars are cheap money, easy to install and you can center up the rear perfectly. I posted a pic (side view) here:
http://www.svtperformance.com/forum...st-tires-stock-svtpp-wheels.html#post13741624

Rear well gap on mine is filled more due to the taller tires. It should look good with what you've got.

 

[crazy4life]

Good God man just slam that thing and be done with it.

 

[YELL03]

I've got those springs (H&R) and I did have to do a panhard bar. Panhard bars are cheap money, easy to install and you can center up the rear perfectly. I posted a pic (side view) here:
http://www.svtperformance.com/forum...st-tires-stock-svtpp-wheels.html#post13741624

Rear well gap on mine is filled more due to the taller tires. It should look good with what you've got.

That looks great. Thanks.

Good God man just slam that thing and be done with it.

You want to take a cruise today, see if traction control works with a foot of snow?

 

[YELL03]

Finally made up my mind....

I ordered the H&R Sport Rear Springs for a 0.75" drop and Maximum Motorsport Rear Bump Stops.

I like the H&Rs, they are rated specifically for a 2011 GT500 Convertible for a 0.75" drop, on a 2010 GT500 it is rated at a 1" drop.

This should maintain a slight rake as the front end will be lower by 0.25" than the rear.

 

[YELL03]

done: