Improving Handling

300bhp/ton said:
What do you want from the car?

Slamming it, with silly low profile tyres and no suspension travel is NOT the way to make it handle!

It may improve lateral grip on a smooth race track like surface but thats about it.

If you want a cheep mod to improve turn in, just change the front geometery setup, setting the car up with less toe in or a little toe out will give you a very immediatley responsive car, it may washout a bit thru the corner.

The downside is the car will also feel more twitchy at speed. But you can't have it all ways. Hence lots of high end performance cars are limited to under 150mph as suspension and aero geometry setups need to be very different if very high speed is involved.

Other things to look at is lowering the cars centre of gravity, but not by slamming the car. You need susepsion travel else it will just crash out against the stops.

Also as its a live rear ultra low profile tyres are pointless unless on a race track. Remember the tyres are the 1st part of the suspension and the only bit actually in contact with the road. Low profile is good as it limits tyre wall roll, but with a live rear you want a bit of movement in the sidewall as the axel setup will NOT cope with it.

Also ditch the panhard and get or make a Watts linkage at the rear.

The ride is pretty firm so you probably don't need stiffer springs, what you do need to revise is the jounce rate and bounce rate. The shocks need to be able to react quick enough to cope with pot holes and such but stiff enough not to crash out on the bump stops.

If you can revise the front/rear weight distribution it will help, maybe relocate the battery to the boot and dry sump the engine with the oil reservior in the boot.

Upgraded bushes (polybush) maybe a good idea but expect less refinment in ride and more road noise.

Slightly stiffer anti-roll bars may help but don't make the car over stiff as this will limit grip. Remember the car should move and lean a bit - allow the suspension to do its job.

If you car looks like its sitting on scaffolding poles when cornering it is WAY too stiff for road use.

Don't go OTT with the rims either, match them to the trye width and profile.


Most of the off the shelf suspension items are more SHOW than GO, they may hint at more lateral grip but unless its usable its pointless. Go for parts and setups that are used and proven on tarmac rally's or road courses NOT race circuits.

Great input, but it leaves a lot of grey areas:
1. What do you consider "slammed"? An Eibach kit that lowers maybe 1"?
2. What tire is "too low pro"? 50 series? 35 series?
3. Have you done research on the '05 GT to consider what parts work the best for THIS car?

Honestly, I really appreciate the time you put into your post, I'd like to know what's "best" for our cars, as most here do, on the street. Anymore input would be great! :nice:
 
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I'm most likey going with the whole saleen setup.

Read the review in MM&FF about how the saleen rides the twistes and handles the bumps. And thats with 20's > I'll be sticking with 17's or 18's the biggest.

quote "every S281 SC gets you Saleen's Racecraft suspension. This gives you N2 struts w/ linear rate coilover springs and a 1.38" tubular swaybar w/ urethane pivot bushings up front. In the rear,........Saleen linear-rate springs, N2 shocks, and a .79" antiroll bar.
Standard rolling stock is 20x9 inch wheels all around with 275/35ZR20 Dunlop sport tires."


" The Saleen rode beautifully , 20" rolling stock and all. It actually soaked up bumps as well as the stock Mustang - some felt it even rode better then stock. We're talking New Jersey's washboard pavement, not Southern CAL's........ Very little harshness makes its way into the cabin, even on the choppiest roads.
Incredibly, this supple suspension came with no tradeoff in grip - quite the contrary. On the MM&FF road course , the S281 SC was 2.47 seconds a lap faster than stock five- speed....."

"Whereas the stock '05 Mustangs plowed miserably on the tight course, the vette and Saleen were incredibly neutral."


Sold me
 
300bhp/ton said:
What do you want from the car?

Slamming it, with silly low profile tyres and no suspension travel is NOT the way to make it handle!

It may improve lateral grip on a smooth race track like surface but thats about it.

If you want a cheep mod to improve turn in, just change the front geometery setup, setting the car up with less toe in or a little toe out will give you a very immediatley responsive car, it may washout a bit thru the corner.

The downside is the car will also feel more twitchy at speed. But you can't have it all ways. Hence lots of high end performance cars are limited to under 150mph as suspension and aero geometry setups need to be very different if very high speed is involved.

Other things to look at is lowering the cars centre of gravity, but not by slamming the car. You need susepsion travel else it will just crash out against the stops.

Also as its a live rear ultra low profile tyres are pointless unless on a race track. Remember the tyres are the 1st part of the suspension and the only bit actually in contact with the road. Low profile is good as it limits tyre wall roll, but with a live rear you want a bit of movement in the sidewall as the axel setup will NOT cope with it.

Also ditch the panhard and get or make a Watts linkage at the rear.

The ride is pretty firm so you probably don't need stiffer springs, what you do need to revise is the jounce rate and bounce rate. The shocks need to be able to react quick enough to cope with pot holes and such but stiff enough not to crash out on the bump stops.

If you can revise the front/rear weight distribution it will help, maybe relocate the battery to the boot and dry sump the engine with the oil reservior in the boot.

Upgraded bushes (polybush) maybe a good idea but expect less refinment in ride and more road noise.

Slightly stiffer anti-roll bars may help but don't make the car over stiff as this will limit grip. Remember the car should move and lean a bit - allow the suspension to do its job.

If you car looks like its sitting on scaffolding poles when cornering it is WAY too stiff for road use.

Don't go OTT with the rims either, match them to the trye width and profile.


Most of the off the shelf suspension items are more SHOW than GO, they may hint at more lateral grip but unless its usable its pointless. Go for parts and setups that are used and proven on tarmac rally's or road courses NOT race circuits.


Sorry, i agree with some of what you say however "Slamming it, with silly low profile tyres and no suspension travel is NOT the way to make it handle!" is incorrect. Maybe in your OPINION you dont like the feel/handling, however lower profile tires provide increased stability and less "mush" feel while cornering. They also allow higher speed cornering and a better feel for the road. Everyone loves to compare BMW's when talking about handling so lets...notice they come factory with 40 and 35 series tires in performance models. I could care less what BMW does i know what works. Also lowering the vehicle is an obvious lower center of gravity advantage and lowering springs were designed to also provide stiffer or stiffer and progressive spring rates to allow less body roll during high speed cornering.....yeah obviously if there is NO suspension travel that is a bad thing it's called a rigid chassis...but too much suspension travel is also a bad thing...stock springs were designed with alot of factors...like how is that 40 year old lady gonna like that when you go flying over a bump....well i dont care i want to feel the road firmly and allow high speed cornering to be a breeze. If you want it to handle well lower profile tires and lower springs will help ENORMOUSLY...is there other things you can do....should you pay attention to how it is aligned to take advantage of the lower springs/tire/shock combo....SURE but that comment in my book is completely OFF. Yes i think its kinda stupid that peope just upgrade wheels/tires and springs just cause its the "thing" to do...but initially someone some gearhead/driver had a reason for doing.
 
I'll tell you one thing... if you're looking for better handling, then I wouldn't lower the car without also installing suitable struts. Otherwise, you will most likely experience underdamping as so many other people do who neglect to upgrade the struts.

Eibach's Pro-System Plus could be a pretty good way to go since it includes struts designed specifically for their lowering springs. Plus, you get stiffer anti-roll bars with the package.

The other option without going to fully adjustable coilovers would be an H&R cup kit. Again, it's a set of springs & struts designed for eachother. H&R hasn't released these for the '05 yet though.