IRS in the new Stang, be careful of what you wish for

[duner]

One of the things that jumped out at me in here is the talk about the ’05 not having IRS or folks wanting IRS.

For you guys wanting IRS on the ’05 you’d better hope Ford designs a much better IRS setup than the ’03 Cobra's.

Here are a few items Cobra guys can do to limit, not eliminate, wheel hop. Keep in mind that no one has zeroed in a solution that works on every car. They all seem to respond to different combos.

On some ’03 Cobras Ford installed the wrong sized mounting bolts. 12mm when it should have been 14mm.
http://www.svtperformance.com/forums/showthread.php?s=&threadid=77363&highlight=wheel+hop

Installing differential and IRS bushings
Not easy to do or expensive to have done
http://www.svtperformance.com/forums/showthread.php?s=&threadid=69011&highlight=wheel+hop

Change the shocks, different tires, add braces, and change the springs.

All cash from my pocket. I read where someone wanted IRS because they don’t drag race. Spirited street driving can induce wheel hop. If the rear tires are spinning more then likely they’re also hopping. Not being able to do a long smokey burnout in my Cobra sucks.

Don’t get me wrong I really like my Cobra. The wheel hop sucks and I’d rather have the ’05 rear suspension. Quite a few guys are swapping the IRS for a live axle.

Just something to consider….

 

[Ron Jeremy]

I have been telling people in here that IRS sucks, but they don't listen. Not only does IRS cost more money, but it's also problematic. I'm glad that the 2005 Mustang doesn't have IRS. Thank God.

 

[fly2low]

In this case, IRS doesn't suck. Ford sucks. How did such things pass the QC inspections? Blame Ford, dont blame IRS.

 

[Ron Jeremy]

I blame IRS because it's not needed in the Mustang vehicles. Put in in some other Ford vehicle, not in the Mustang.

 

[shatner saves]

Bolts?
Bushings?!?

Obviously this proves that IRS is fundamentaly inferior to live axle.

My 92 has a live axle in it, complete with 4 trailing arms and quad shocks and if I put anything more grippy than an all season tire on it, the axle hops like crazy when I break the tires loose. There is a reason why the aftermarket does such a healthy business selling bushings and control arms for these cars.

 

[duner]

My post wasn't meant to imply that all IRS sucks. There are plenty of sports cars out there with IRS that manage wheel hop a hell of a lot better than Ford did on the Cobra. Mustangs are not sports cars. The IRS setup on the Cobras is a half-assed attempt. I wouldn’t mind an IRS that functions properly without the hop. My Cobra rides real nice on the highway and side streets.

 

[65conv50]

Where they really need the IRS is on the V-6 versions. Most of the buyers of those cars don't know and don't care what kind of axle it has, but will really know when it doesn't "ride and handle" as good as other cars. That could make a real difference in sales. I said it before and stand by it: it should have had IRS, with live axle available as an extra cost option for those few who are going to drag race it. No engineering involved as the platform they are using is already on the market with IRS.

 

[Z28x]

I'm happy with the Cobra IRS setup.

THe '05 Mustang is the Only RWD car on the Market not using IRS. Like one person said, if it sucks, it's not because IRS sucks. It is because Ford sucks at making IRS.

I'm sure the 06 Cobra IRS will be better because Ford will have more experience. THe Lincoln LS has been out since 2000 and that is closer to what the '06 Cobra will be based off.

 

[Rootus]

My 92 has a live axle in it, complete with 4 trailing arms and quad shocks and if I put anything more grippy than an all season tire on it, the axle hops like crazy when I break the tires loose. There is a reason why the aftermarket does such a healthy business selling bushings and control arms for these cars.

That's not normal, though. I have no problem with nice grippy tires, I haven't ever had wheel hop on any of my six Mustangs except for my 1999 Cobra. If every bushing is stock, and the quad shocks are too, then I could see it hopping... that's a 12 year old car.

And as you just mentioned the problem is not necessarily the live axle, it's the crappy quadra-bind setup that suspends it.

 

[XtorT'r]

One of the things that jumped out at me in here is the talk about the ’05 not having IRS or folks wanting IRS.

For you guys wanting IRS on the ’05 you’d better hope Ford designs a much better IRS setup than the ’03 Cobra's.

Here are a few items Cobra guys can do to limit, not eliminate, wheel hop. Keep in mind that no one has zeroed in a solution that works on every car. They all seem to respond to different combos.

On some ’03 Cobras Ford installed the wrong sized mounting bolts. 12mm when it should have been 14mm.
http://www.svtperformance.com/forums/showthread.php?s=&threadid=77363&highlight=wheel+hop

Installing differential and IRS bushings
Not easy to do or expensive to have done
http://www.svtperformance.com/forums/showthread.php?s=&threadid=69011&highlight=wheel+hop

Change the shocks, different tires, add braces, and change the springs.

All cash from my pocket. I read where someone wanted IRS because they don’t drag race. Spirited street driving can induce wheel hop. If the rear tires are spinning more then likely they’re also hopping. Not being able to do a long smokey burnout in my Cobra sucks.

Don’t get me wrong I really like my Cobra. The wheel hop sucks and I’d rather have the ’05 rear suspension. Quite a few guys are swapping the IRS for a live axle.

Just something to consider….

Hey if those guys are swapping the irs.. I might be interested in buyin one. heh.. I like them cuz I don't drag.

 

[shatner saves]

I'm happy with the Cobra IRS setup.

THe '05 Mustang is the Only RWD car on the Market not using IRS. Like one person said, if it sucks, it's not because IRS sucks. It is because Ford sucks at making IRS.

I'm sure the 06 Cobra IRS will be better because Ford will have more experience. THe Lincoln LS has been out since 2000 and that is closer to what the '06 Cobra will be based off.

Ford has plenty of experience building IRS setups. I think any issues people have with the cobra IRS has more to do with the fact that it's a compromised setup than anything else. If you're trying to retrofit a system to fit in a 25 year old chassis and you're limited to using the existing mounting points, of course it's going to a little short. I can't think of any other time someone has tried to do this.

I'm glad you like the way your car handles. Have you ever driven a resent live axle mustang, and if so, is there any difference?

If the new chassis really was designed with IRS in mind, and Ford considered all the complaints when designing it (ie axle hop), the new system will be head and shoulders above the old.

 

[fly2low]

They really need to watch the QC of the Mustang. Surely it is not the most expensive car in their line, but it is the one with most sentimental value. So, it's right at the spot of the attention from everyone.

 

[RydeOn]

Bolts?
My 92 has a live axle in it, complete with 4 trailing arms and quad shocks and if I put anything more grippy than an all season tire on it, the axle hops like crazy when I break the tires loose. There is a reason why the aftermarket does such a healthy business selling bushings and control arms for these cars.

You should get that looked into. I havent driven a solid axle mustang that hopped, including mine. In fact my suspension is totally stock and Im running alot more power than stock and much grippier tires. It is smooth as glass if I give it too much throttle and spin the tires.

I say Ford should build an IRS if it outperforms the solid axle in every way. But I honestly could not see Ford able to make that happen, so...

The new solid axle will rock so dont worry about it!

 

[shatner saves]

They really need to watch the QC of the Mustang. Surely it is not the most expensive car in their line, but it is the one with most sentimental value. So, it's right at the spot of the attention from everyone.

I think the fact that ford has moved production from the rouge river plant to flat rock is a good sign. I'm sure ford, with the beating they've taken over the last few years, it keeping a much closer eye on quality. They have too much riding on their new vehicle introductions this year to have another Ford Focus debacle.

 

[Omegalock]

Where they really need the IRS is on the V-6 versions. Most of the buyers of those cars don't know and don't care what kind of axle it has, but will really know when it doesn't "ride and handle" as good as other cars. That could make a real difference in sales. I said it before and stand by it: it should have had IRS, with live axle available as an extra cost option for those few who are going to drag race it. No engineering involved as the platform they are using is already on the market with IRS.

A live axle will ride and handle just as well as an IRS in normal daily driving. The average V6 driver wouldn't be able to tell the difference in an IRS and live axle going from home to the mall or home to the office or home to school.
And why should they make the car with the higher cost IRS thusly a higher base price all around...and THEN add the cheaper live axle setup and charge the people that want a live axle even more. That doesn't make sense. You don't start with the high price equipment then add an option to add the low price equipment for even more money. You offer a delete option that allows you to replace the high priced crap with the low priced crap thusly lowering the price. Or you build the base model witht he low priced stuff and THEN you add the option to pay more to get the more expensive stuff.

 

[shatner saves]

Sorry to post 2 in a row.

If you go through http://www.svtperformance.com/forums/showthread.php?s=&threadid=69011&highlight=wheel+hop
you will notice something interesting. The bushings they serviced, which seemed to significantly reduce the wheel hop, are actually peripheral to the IRS assembly.

They replaced the bushings at the diff and subframe mounting points, not the upper or lower control arm bushings or anything internal to the system.

That begs the question: Is there anything really bad about this setup or is it just the way it was incorporated into the chassis?

 

[mp67]

I'm happy with the Cobra IRS setup.

THe '05 Mustang is the Only RWD car on the Market not using IRS. Like one person said, if it sucks, it's not because IRS sucks. It is because Ford sucks at making IRS.

I'm sure the 06 Cobra IRS will be better because Ford will have more experience. THe Lincoln LS has been out since 2000 and that is closer to what the '06 Cobra will be based off.

Yeah thats true. The platform for the 03 and earlier cobra's were designed for solid axle. They came along and shoehorned an IRS into a solid axle design. Next cobra will be designed for IRS and should be better. And as for wheel hop with spirited driving, not everyone believes spinning the rear wheels is spirited driving. The more your wheels spin, the slower you are. If I want to get around a corner quickly, I don't want to be fishtailing.

 

[Z28x]

If I want to get around a corner quickly, I don't want to be fishtailing.

I love kicking it sideways around corners

It will be interesting to see how different/better the '06 setup is from the '03/04

 

[GelatiCruiser]

My boss has a 2002 (I think) Lightning. When he tears ass sometimes the entire bed of the truck looks like it's going to hop off of the truck. It's freaky. I don't know if the L has IRS (I think it does)....but it hops like mad! These links = Good info.

 

[mp67]

I love kicking it sideways around corners

It will be interesting to see how different/better the '06 setup is from the '03/04

Thats always good fun, I was just saying in a road race case it would slow you down. Of course, I would never break the law by spinning my tires on the street.