Sleeper_08

RodeoFlyer

Sorry if I didn't express myself clearly enough but I did not say that a Mustang would ever race against an F1 car.

As you are aware all cars are designed to meet certain criteria whether they are race cars or street cars. IMHO no car designed today selling at the price level of a Mustang should have anything other than IRS. If Ford chose to leave it off to save money or appease the 1/4 mile crowd then that was their choice and again IMHO the wrong choice.

The point I was trying to make was if the class you are racing in, and by this I meanraces where the carsturn both left and right, allows the use of IRS then the designers will use it.

Sam Strano

The notion of "handling" is varied.

I see it has a culmination of outright grip, balance, stability and even ride (because a brick stiff car won't hold a not-so-smooth very well).

A Corvette is very, very different from a pony-car. Not only that, there are many different levels of Vette suspensions as well. I frankly don't think a base car "handles" all that great, and the Z06 to my taste in stock form doesn't handle as well as a Z51 (current cars).

I won't shine you on here. You're talking about a taller car with an less, um... polished suspension design. Can you make them fast? Hell yes... but it's not a Corvette.

I think I can give you an idea about what I can do with pony-cars. It's a Chevy story, so bear with me. As many of you know I autocross pretty competitively. I setup my own cars as well as some others that have won National Championships. In 2006 I ran my Camaro in ESP (E-street prepared) @ Nationals. A friend and customer (and even my boss @ Evo schools) ran his 2002 Z06 in ASP. We both won our classes, and both by a pretty good margin. Over the course of the two days, we ended up about 2 seconds apart (that's over 100 seconds of run time). Yes, he was faster. But let's compare the cars:

Z06 Camaro
Weight 3000 3400
wheels 17x11/12 17x11
tires315/335 315
Power392 RWHP360 RWHP (both on dynojets, made 321 on a Mustang)
Gearing -12% (shorter) +12% (taller)

Both cars were on Hoosier A6's. Both of us are equal drivers (each has beaten the other in like and sometimes the very same car). I was involved in the setup of both. Both run the same category for SCCA and are allowed the same kind of mods. Working outside those rules might have made my car faster, but you would no longer be comparing apples to apples.

You can see that a pony-car can be made quite quick. But it's not a Corvette. I'd have hammered a base Vette on time, and was closerin time yet to Super Stock Z06's. And I ran in worse conditions (the worst actually) than SS or ASP did being I ran 8 AM first day. No rubber down, no grip. Conditions improve with runs, and that worked for me this year in the Shelby, but I digress.

RodeoFlyer

Sleeper -

You're comments clearly show that you really just - don't know what you are talking about.

What about the price level makes you think the Mustang should have an IRS? The friggin car is only 25 grand! The Mustang will STILL outsell the new Camaro when it comes out (a few years late - just like in the 60's) as it ALWAYS has. Guess why - because the Camaro costs TOO MUCH. Ford built the car without the IRS because it is expensive, problematic, and heavy. You're entitled to your opinion, but i'm certain there is a large group of engineers and bean counters at FoMoCo that KNOW that the choice they made was sensible.

Regarding using it for racing - clearly you don't race. Good luck finding a sanctioning body that allows an IRS to be put in the car. The NASA American Iron rules allow the Cobra factory unit under updating/backdating rules - but that's it. Hmm - both the AI and AIX National Champions are in Fox-bodied cars sitting on stick axles. They seem to get by the guys in the pack running Cobra IRS'.

BOTH of my current Mustangs will run around a base model 'vette. If I had a supercharger I could run just find with the Z06's. And i'd be doing it for a lot less than the 75k price tag of a Z06.

And once again - IF the GAC cars had IRS.....how much MORE power do you think they would be penalized? The S197 has been kicking *** in EVERY racing series it has been in since 05. I'm pretty sure they know what they are doing.

Sleeper_08

RodeoFlyer

You are correct, I have been directly involved in racing for a long time and didn't say I was.

A couple of points;
1) How many other cars released since 2005 selling around the Mustang's price have not had IRS? I can't think of any but I am and old guy so my memory may be weak.

2) I considered buying a Corvette as from my research they offer the best bang for the buck. Unfortunately buying a car is more than economics and Corvette's just don't appeal to me but as soon as I saw the '05 I knew I wanted one.

3) Hopefully by the time I'm finished mystock looking Mustangwill be fast enoughand I'll learn how to drive it well enough to blow the doors off a few Corvettes or Porsches at some track days. Then see how big my grin will be.

4) As for the new Camaro I wouldn't have one if it was given to me. On the Mustang Ford nailed the styling right on. For the Camaro GM got it all wrong.

UrS4

While I don't want to get in the middle of this amusing dialogue, I will share a possibly more relavant story regarding the corvette vs S197 with a stick axle.

I ran my GT at BIR in MN with the only mods of a CAI+tune. Stock everything else! My two instructors before I solo'd in the new car both drove C5 corvettes, one a Z51 and the other a Z06. Their cars were stock minus better pads and tires.

They both had driven plenty of older mustangs but never the S197 chassis. Both commenting while driving that they could not believe how well the car handled and how the stick axle never showed typical stick axle handling tendencies. They both said it was the best solid axle car they had driven on the track and were quite impressed.

The previous posters videos show a properly set up S197 can equal or better a stock C6 vette and for less money.

Sleeper_08

UrS4

Your story supports the idea that the S197 with a solid rear axle is a well engineered package and can be made to handle pretty well and I completely agree with it. That is one reason I bought the car.

I just wish Ford had done it right and put in a well designed IRS because then it would have been even better!

UrS4

I agree the car would handle better and I noticed some of the stick axle waggle when I first got it, since I could still drive my Audi before I sold it.

But, whether you agree with Ford as to why they put a solid axle instead of an IRS, if they had, there would be more people complaining about the wheel hop and poor ability or IRS to put down a lot of power well. Just ask the terminator crowd. Ford did a good job with the suspension redo and for the money, power level, rwd platform, its pretty good.

You sound like handling is more important so a stick axle sounds cheap.

Another little tidbit about stick axles. Superformance, factory five racing, and other AC cobra replica car companies have an opinion on using stick axles in their kit cars. Obviously being a kit car, you can use a lot of mustang running gear, usually 87-04 components. You can however, go with 3 different rear end suspensions from most of these compaines, the traditional mustang rear end and quad link, an upgraded watt's link with solid axle, and an IRS usually out of a linclon. When comparing the three, these companies state that using the stick axle and watt's link is the fastest around the track and the IRS is second but more for 'comfort'. Take it for what its worth, some cars can just be made quicker with a stick axle. However, this may be due to space requirements only allowing for an antiquated IRS setup, which could be inferior.

Sleeper_08

UrS4

Your comments on the Cobra relpicas are right on. If Ford put a low cost poorly designed IRS on the Mustang then we would have all been losers. The real beauty of a solid axle is 0 camber change on a flat surface and doing that with IRS is pretty tough. A major disadvantage is the high unsprung weight.

If you do it properly even a terrible desin can be made to perform well and the Porsche 911 is the best example of this, after all who in their right mind would build a performance car with the engine behind the rear axle?

Norm Peterson

I think I'd put stick axle toe control right up there as well. Individual rear toes that wander much and total rear toe that does not remain constant (whether these are caused by geometry or any number of compliances) feels slightly"nervous". You tend to not drive a car quite as hard when you're not completely sure it's going to do only what you tell it to do.

UrS4 - I'm not surprised by the comments of your instructors. The 3-link/PHB is arguably at the top of the heap for the "simple" stick axle suspension linkage arrangements, with the torque arm being relatively close. Either is better up toward the cornering limits than the converging (aka triangulated) 4-link mess that holds up the rear of the Fox/SN95/my thumbnail car. Not to mention that as cars get heavier (S197 vs Fox, for example), a given stick axle becomes slightly less of a disadvantage (think sprung:unsprung ratio).


Norm

[IMG]local://upfiles/62186/1BDA74540CC54D3A89891C1E6A3E07E0.jpg[/IMG]

SlideWRX

Well this discussion lit right up!

My arguement vs Forumla 1 would be that they don't use a Macpherson strut front suspension either, but no-one seems to complain about that on the Mustang (except maybe griggs? ).

Itisn'tthe *most* effective, but it is a *very* effective suspension design. As someone pointed out, the Grand-Am Cup Mustangs are competing quite well against BMW's & Porsche's. When Nascar goes to the road course, they are still using a solid axle and turning in fast times.

Heck, there's a guy running rallies in a Fox body mustang with a solid axle winning in 2wd.
http://www.mayhemracing.com/mrcars.html

The poor reputation of the solid axle stems from being on a car without good handling; i.e. the mustang. Specifically the previous chassis. the chassis was flexible, the front suspension wasn't anything great either, and the four link didn't handle bumps well. Not to mention all trucks have it, and they use an even simpler, worse handling suspension setup. To really debate irs vs solid, you need to go into unsprung weight, control arm geometry & roll centers & a bunch of other stuff. One could write a book comparing the two!

Personally I wish ford had an independent option to purchase through ford racing or something, mostly for better street ride. At auto-x the car handles great; no need for IRS.

Tom