Suspension Advice? - 2007 GT500 - Front end feels 'light' at 90mph+

Hoping you guys can offer some advice or direct me to a specialist who maybe wouldn't mind talking with me about my Shelby.

So I've had this car since nearly new (5000 miles) - it came with the Ford Racing handling pack (m-fr3a-msvta) and maximum motorsports Caster/camber plates (MM5CC-1). However I didn't get the alignment specs.

Well fast forward 8 years (back in 2018 or so) and I replace the shocks/struts/springs. Lived in an area that had some poor local roads and felt they might need replacing (in hindsight this was probably a bad idea).

Go for a alignment from a reputable alignment shop (based of asking around, various reviews etc - by no means a performance specific shop) and haven't been happy since. Feel like the steering wheel has a little play (not enough, but enough to bother me), is more influenced by imperfections in the road, and at high speeds the front gets kinda light and it almost feels scary.

It's fine under 60mph, but who wants to keep their Shelby under 60mph? I'll never be able to drag the car at a track as it either. The car used to drive like it was on rails. I could hit crowns/imperfections and it would still drive straight, even with my hand off the wheel. The wheel had no play in it, etc. Was a joy to drive.

Ever since that change, I've been playing with trying to get it back to like it was. I've had alignments done multiple times, I've had the struts out a few times trying to see if maybe fitment was off or something small was missed. Even tried pulling the caster/camber as I feel trying to chase down the proper alignment with them is turning out to be way harder than I would have ever expected. I can't come up with any smoking guns.

Anyway, I'm willing to try a different brand of struts. Even willing to change springs (but hoping to find one that'll work well with the M-5300-L's that are in the car).

Anyone have the M-5300-Ls (or the ford handling pack I have) and changed to a non-ford strut? Any recommendations? Any alignment gurus who maybe have this pack and caster/cambers that could share alignment specs I could maybe try on my car (I realize each car is slighty different).

Anyway, appreciate your guys' time - I know this likely isn't a simple answer, but I'm kind of out of ideas and I don't want to just 'live with it'.

Stock alignment specs:

Caster = +7.1* +/- .75* (passenger side +.25* to +.5* to counter road crown)
Camber = -.75* +/- .75*
Toe = +.10* +/- .20*

My alignment specs with H&R, Bilstein, and Maximum Motorsports components:

Caster = L +6.75*, R +7.00*
Camber = L -1.25*, R -1.25*
Toe = 0*

I also have a fully adjustable rear suspension that is squared up with the front end.

-1.25* Camber is the most you want for a street car, before inside tire wear starts to become an issue. My car drives like it is on rails at all speeds, and a Maximum Motorports K-member with accessories takes it to another level. Check out this thread: Winter mod review

I'd definitely take it to a Ford dealership. They should use stock specs. Mention it and make sure they do.

Appreciate the feedback.

SCGallo - can I ask what part#'s you use for your front susp? (If you know them offhand)

Cobracide - but it's not stock components. Car's lowered, etc. I assume stock specs would be of no value?

valgorite said:

Appreciate the feedback.

SCGallo - can I ask what part#'s you use for your front susp? (If you know them offhand)

Cobracide - but it's not stock components. Car's lowered, etc. I assume stock specs would be of no value?

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Since it's not right, I'd go to stock caster/camber and see how it is and work from there. Have you checked your tire wear to detect improper adjustment?

I run a M-FR3A-MSVTA suspension kit and I recall there are two different recommended alignment settings in the installation instructions. I went with the more aggressive alignment and don't have any irregular wear or other issues. I'd imagine one can find the instructions PDF rather easily on the internets.

Well stock settings aren't going to work on a lowered car, is how I understand it.

Alignment, generally, feels fine. No abnormal wear on tires. It doesn't wander unless there is road crown or the like. Driving around in the city is fine, though the car reacts more to input from the road (bumps, potholes, round-abouts, etc all impact steering more than it used to (sounds like bumpsteer, but I've never had a bumpsteer kit anyway). It's not as good as it used to be, but after several alignments at various shops it feels like a vain pursuit for a small detail, but it bugs me.

My concern, primarily, is at higher speeds. It's definitely not 'rock solid' and frankly it feels dangerous.

Verify the install was done properly at a Ford dealer. It's a Ford kit so they should know what they are doing with it.

Last Page
Factory Spec Camber Caster Total Toe
Front -0.75 7.1 0.22
Rear N/A N/A .05
Ford Performance Spec Camber Caster Total Toe
Front -1.2 7.1 0.22
Rear N/A N/A .05

This is useful. Did a google came up with this - https://performanceparts.ford.com/download/instructionsheets/FORDINSTSHTM-FR3A-MGTA.PDF

Comparing the specs on the last page with my most recent alignment ....they're quite close.

My report is:
Caster - L: 7.9, R: 7.1 (specsheet says 7.1 each). Believe my left is more to compensate for the driver.
Camber - L: -1.3, R: -0.9 (specsheet says -1.2 each)
Toe - 0.05 (specsheet says 0.22

Anyone know if these differences are significant?

valgorite said:

SCGallo - can I ask what part#'s you use for your front susp? (If you know them offhand)

Click to expand...

Had to look through my records... but here you go:

H&R Sport Spring kit – 51655-500
H&R Sway Bar - 70655
BMR end links – ELK010
Ford Performance lower control arms – M-3075-E
Bilstein HD Struts – VE3-C871-H0
Maximum Motorsports Caster Camber plates – Mm5CC-1
MM K-member – Mm5KM-7
MM Bumpsteer kit – Mm5TR-2

valgorite said:

My report is:
Caster - L: 7.9, R: 7.1 (specsheet says 7.1 each). Believe my left is more to compensate for the driver.
Camber - L: -1.3, R: -0.9 (specsheet says -1.2 each)
Toe - 0.05 (specsheet says 0.22

Anyone know if these differences are significant?

Click to expand...

I do not know how the differences would affect the steering feel, but my anal retentiveness would not allow me to leave it that way. If it were my car, I would reduce positive caster on the left side and increase negative camber on the right side, in an effort to get the measurements more symmetrical, then re-check toe; the subtle changes would only make it better. Speaking from experience, those would be really small adjustments on the caster camber plates if you still have them installed.

Go get your car realigned. That shop most likely did a "toe n go", where they only actually check/change toe angle and send it out the door as long as the rest of it is "close enough".

Your caster is definitely out of range, off nearly a full degree. That should be enough to notice and could be what you're feeling at speed.

The camber is off but the total amount and differential isn't enough to matter on the street. It's actually in range but still, it shouldn't be more than a tenth or two off at most considering the age of the car/components. You got a shitty alignment by a lazy tech, incompetent tech, or both. If the parts wouldn't allow for enough range, a good tech would've informed you regardless of it being a performance shop or not.


Factory specs are pretty good but allow for WAY too much variation. Here's the specs:

Camber
-0.75°, with a 0.75° cross camber tolerance

Caster
7.1°, with a 0.75° cross caster tolerance

Toe
0.10 total toe with a +/- 0.20 tolerance

OEM alignment is just fine for a lowered car, the trick is to have the adjustability to get back to stock settings. Toe will be the most important (most negative effect) on a lowered car, then camber, then caster. Have the alignment shop adjust everything to OEM except camber. Tell them to get - 1.2° to -1.4° camber, or as much as they can get and still keep it even. It'll drive like factory and will give you better tire wear if you drive aggressively on the street. If you wear white new balances, tuck a polo shirt in to your jorts, and wear a belt, set the camber to -0.75° as you won't be the kind of guy that will benefit from increased camber.

valgorite said:

Hoping you guys can offer some advice or direct me to a specialist who maybe wouldn't mind talking with me about my Shelby.

So I've had this car since nearly new (5000 miles) - it came with the Ford Racing handling pack (m-fr3a-msvta) and maximum motorsports Caster/camber plates (MM5CC-1). However I didn't get the alignment specs.

Well fast forward 8 years (back in 2018 or so) and I replace the shocks/struts/springs. Lived in an area that had some poor local roads and felt they might need replacing (in hindsight this was probably a bad idea).

Go for a alignment from a reputable alignment shop (based of asking around, various reviews etc - by no means a performance specific shop) and haven't been happy since. Feel like the steering wheel has a little play (not enough, but enough to bother me), is more influenced by imperfections in the road, and at high speeds the front gets kinda light and it almost feels scary.

It's fine under 60mph, but who wants to keep their Shelby under 60mph? I'll never be able to drag the car at a track as it either. The car used to drive like it was on rails. I could hit crowns/imperfections and it would still drive straight, even with my hand off the wheel. The wheel had no play in it, etc. Was a joy to drive.

Ever since that change, I've been playing with trying to get it back to like it was. I've had alignments done multiple times, I've had the struts out a few times trying to see if maybe fitment was off or something small was missed. Even tried pulling the caster/camber as I feel trying to chase down the proper alignment with them is turning out to be way harder than I would have ever expected. I can't come up with any smoking guns.

Anyway, I'm willing to try a different brand of struts. Even willing to change springs (but hoping to find one that'll work well with the M-5300-L's that are in the car).

Anyone have the M-5300-Ls (or the ford handling pack I have) and changed to a non-ford strut? Any recommendations? Any alignment gurus who maybe have this pack and caster/cambers that could share alignment specs I could maybe try on my car (I realize each car is slighty different).

Anyway, appreciate your guys' time - I know this likely isn't a simple answer, but I'm kind of out of ideas and I don't want to just 'live with it'.

View attachment 1735017

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You need to stick with a performance struts like ones in the kit or something like the Koni yellows, Tokico adjustables, ect. The frpp handling kit was great compared to stock.

Make sure your camber specs are the same? They can both be in range and not match. With a lowered car, you can still use factory specs. However, you will never be able to attain caster/camber specs without an adjustable strut mount. Have you ever checked your ride height on the front left to right? Has anyone inspected the tie rod ends and ball joints for excess wear? Are the liquid filled bushing on the front control arm leaking?

I think your driving to slow. Bump up to 120 or so and see if that helps

grab a Tiger Racing hood. it will allow the trapped air under the hood to escape and make the car more planted. same principle for the hood Racebronco developed for the terminators.

you could also slap a pair of turbos on the front of the car to help weigh it down lol

Steve@TF said:

grab a Tiger Racing hood. it will allow the trapped air under the hood to escape and make the car more planted. same principle for the hood Racebronco developed for the terminators.

you could also slap a pair of turbos on the front of the car to help weigh it down lol

Click to expand...

Steve, any chance of doing another run of hoods for terminators?

T3RM1N8R_18 said:

Steve, any chance of doing another run of hoods for terminators?

Click to expand...

no sir. i received the last batch a few months ago. all full carbon fiber. one just sold and i have pending sale on the last three.

Steve@TF said:

no sir. i received the last batch a few months ago. all full carbon fiber. one just sold and i have pending sale on the last three.

Click to expand...

Thanks, let me know if anything changes I would be interested.