Interested in tightening up the suspension

[Drive XR7]

Have a 2003 Vert, 28k miles, with subframe connectors, built IRS, H&R race springs, OEM Bilsteins. It doesn't really feel sure footed under acceleration or around corners. I expect some of this due to the vert but wondering if replacing the OEM shocks and struts is a good idea, they were old now. Is this a common item to replace at this age? Or what do folks suggest?

 

[01yellercobra]

What tires and when was the last time you had an alignment? Also check the hub nuts. If they loosen up things move around.

 

[HudsonFalcon]

I think they recommend the HD Bilsteins with the H&R Race springs.

I have the exact same setup as you except I have the HD’s and my car feels solid and level around corners.

Running Continental Extreme Contact Sports in the rear and Nitto 555 in the front.

 

[Drive XR7]

What tires and when was the last time you had an alignment? Also check the hub nuts. If they loosen up things move around.

I have 555 g2s up front and 295/35/18 NT05s on the rear, but these are brand new and I haven't had a chance to really put it through the paces yet. I'll check the hub nuts too. I've heard some stories of these loosening up too.

 

[Drive XR7]

I think they recommend the HD Bilsteins with the H&R Race springs.

I have the exact same setup as you except I have the HD’s and my car feels solid and level around corners.

Running Continental Extreme Contact Sports in the rear and Nitto 555 in the front.

Good call. Are these the B6s? Is there any reason not to run B8s?

 

[HudsonFalcon]

Good call. Are these the B6s? Is there any reason not to run B8s?

I think the B8’s are for the Cobra R?

Here’s a link to what Maximum Motorsports recommends for spring/damper combos.

Matching spring rates with dampers

 

[Blkkbgt]

I would definitely replace your shocks and struts for starters.

Also take a hard look at all your bushings. Rubber degrades over time just sitting. If your control arm bushings are cracked they need to go.

Check your toe links and cross axis joints as well.

You didn't mention if you have CC plates. If not I'd get a set.

 

[01yellercobra]

As mentioned look over the bushings. What was replaced in the IRS? The car wandering under acceleration makes me think something mechanical. When I had that happen to me it was a hub nut issue.

Aren't the NT05 a drag radial? Or more similar to the R888R? If so I don't think you're ever going to get 100% sure footed with your tire set up. You're running a race tire in the rear and a summer performance tire in front.

 

[robvas]

As mentioned look over the bushings. What was replaced in the IRS? The car wandering under acceleration makes me think something mechanical. When I had that happen to me it was a hub nut issue.

Aren't the NT05 a drag radial? Or more similar to the R888R? If so I don't think you're ever going to get 100% sure footed with your tire set up. You're running a race tire in the rear and a summer performance tire in front.

There is a NT05 which isn't a drag radial (like the NT05R), it's supposed to be their highest performing regular street tire. 200 treadwear type of thing.

 

[Drive XR7]

Thanks guys.

The IRS was rebuilt with FTBR's complete IRS bushing kit. I don't have CC plates and didn't think I needed them, I see no abnormal wear on the front tires but admittedly never saw the alignment report.

I will replace shocks/struts on all four corners (1999-04 Bilstein HD (B6) series Damper Package, IRS Cobra Mustang), and will double check the axle nuts.

The NT05s are max performance summer tires. I'd love to run them front and rear, and will replace the my current 265/35 555G2s with 275/35 NT05s when they wear out. You may be thinking of the NT01s, they are a track tire.

 

[Blkkbgt]

Thanks guys.

The IRS was rebuilt with FTBR's complete IRS bushing kit. I don't have CC plates and didn't think I needed them, I see no abnormal wear on the front tires but admittedly never saw the alignment report.

I will replace shocks/struts on all four corners (1999-04 Bilstein HD (B6) series Damper Package, IRS Cobra Mustang), and will double check the axle nuts.

Good to hear your IRS is already built.

CC plates are important on these cars because they not only better connect the struts to the car they also allow better articulation as the wheels turn. The other benefit is an easier alignment.

Speaking of alignments. Find a good shop that knows what a good alignment is. In spec doesn't mean it's actually good.

You want your camber and caster matched side to side not just "in spec". Shops will send you out the door having slight positive camber on one side and slight negative on the other because it's within "spec".

The first way to vet a shop out is ask about setting up the car to your specs, I suggest MMs recommendations they list in the CC plate instructions. If they say no move on.

 

[01yellercobra]

Good to hear your IRS is already built.

CC plates are important on these cars because they not only better connect the struts to the car they also allow better articulation as the wheels turn. The other benefit is an easier alignment.

Speaking of alignments. Find a good shop that knows what a good alignment is. In spec doesn't mean it's actually good.

You want your camber and caster matched side to side not just "in spec". Shops will send you out the door having slight positive camber on one side and slight negative on the other because it's within "spec".

The first way to vet a shop out is ask about setting up the car to your specs, I suggest MMs recommendations they list in the CC plate instructions. If they say no move on.

This. When you start getting rid of rubber bushings you have less give in the suspension. So little things out of whack are easier to feel.

I managed to find a shop that deals with high performance stuff. When I went there the first time they asked how I wanted my car set up. They gave me a middle of the road alignment that would give some handling and wouldn't kill my tires in 500 miles.

Something else to check is your air pressure. Play with it a little. But make sure it's the same side to side. I run my R888R's around 32psi. I'm still messing with the TQ's, but they seem happy at 26 so far.