Any sold axel regrets ??

[ruthless]

I would switch again! The IRS at my power level, even with the full tilt boogie upgrades and the MM brace, just never felt planted when launching or running hard on the street. The SRA and the baseline suspension kit plant the rear of the car and hold it straight. My first drive on the highway had me smiling ear to ear after I stomped the throttle. The back end bit and the front came up launiching the car. Now when I did that with the IRS I could feel it walking around as it was digging for traction and it was just a very odd disconnected feeling. Even watching my dyno vid in my sig you can see the rear drivers side wheels toe in. Now imagen how bad it was when I was leaving in boost off the trans brake. OUCH!!

SRA for the win in my case.
1. Lighter
2. Stronger
3. More traction

I honestly cant see were I lost much ride quality with my setup. Now compairing the IRS to a stock SRA setup I can see some peoples point.

 

[cdnstang]

weight savings is neglible between irs and solid axle. All depends on what your doing with the car at the end of the day. Dont forget to reinforce those torque boxes ;-)

If i was to swap out to solid axle, I would go with a good set of lowers and delete the uppers and go torque arm. Just too much binding in the stock 4 link for my liking. Dont forget to do a panhard bar to keep that diff centered.
Just really tight under there not to mention trying to fit 3" exhaust as well. lol

 

[ruthless]

EDIT: Ah who cares

 

[Shadow Grey 03]

weight savings is neglible between irs and solid axle. All depends on what your doing with the car at the end of the day. Dont forget to reinforce those torque boxes ;-)

If i was to swap out to solid axle, I would go with a good set of lowers and delete the uppers and go torque arm. Just too much binding in the stock 4 link for my liking. Dont forget to do a panhard bar to keep that diff centered.
Just really tight under there not to mention trying to fit 3" exhaust as well. lol

100lbs isn't a decent weight savings?

 

[ac427cobra]

100lbs isn't a decent weight savings?

Yes, it's a good weight savings for someone that likes going fast in a straight line, I will grant you that.

But...... a Terminator, much like every other Mustang, is a front end heavy vehicle. It has a poor F/R weight distribution that's 57/43. This poor weight distribution affects handling and performance. By removing 100# from the rear of the car you are making that lopsided F/R distribution even worse. Plus you have to factor into the equation the significant increase in unsprung weight in the rear suspension when converting to an SRA. And as far and handling goes, you'll be fighting the infamous "quadra bind" of the SN-95 four link SRA.

Some "SRA conversion" food for thought.

:thumbsup::coolman::beer:

 

[SuperSport01]

Op since your not worried too much about going to the track just get a bushing kit from FTBR. 99% of the time wheel hop is going to break something before dumping the clutch will.

 

[ruthless]

Yes, it's a good weight savings for someone that likes going fast in a straight line, I will grant you that.

But...... a Terminator, much like every other Mustang, is a front end heavy vehicle. It has a poor F/R weight distribution that's 57/43. This poor weight distribution affects handling and performance. By removing 100# from the rear of the car you are making that lopsided F/R distribution even worse. Plus you have to factor into the equation the significant increase in unsprung weight in the rear suspension when converting to an SRA. And as far and handling goes, you'll be fighting the infamous "quadra bind" of the SN-95 four link SRA.

Some "SRA conversion" food for thought.

:thumbsup::coolman::beer:

With all that said you still have to admit that at a certain point that IRS is a bigger pita then its worth. My car was just trying everything it could to twist that thing out from under my car. I had every upgrade you make plus a few that you don't.

Not arguing just saying that the IRS has its limits.

 

[ac427cobra]

With all that said you still have to admit that at a certain point that IRS is a bigger pita then its worth. My car was just trying everything it could to twist that thing out from under my car. I had every upgrade you make plus a few that you don't.

Not arguing just saying that the IRS has its limits.

People that come to me for advice that have 700-800 RWHP and above I tell them straight out that they are pushing the limits of the IRS. (this is a relatively small group of Cobra owners) A LOT depends on their intended use for the car. If they NEVER drag race and rarely dump hole shots, the IRS will serve them well, particularly when they upgrade toe links, install a bumpsteer kit and ACTUALLY bumpsteer their suspension, which is VERY important at high power levels. The higher the power level, the more important bumpsteering becomes. With upgrades like the new improved Ford Racing rear cover, failures will be fewer and farther between.

I cut my teeth open tracking and racing teeth with an IRS. There is not a single doubt it my mind the IRS makes me a better and faster driver than what I actually am. I get into my 2012 Boss 302S and I feel like I somehow forgot how to drive. I can't control the ass end of the Boss like I do my other IRS equipped cars.

FWIW

 

[Shadow Grey 03]

People that come to me for advice that have 700-800 RWHP and above I tell them straight out that they are pushing the limits of the IRS. (this is a relatively small group of Cobra owners) A LOT depends on their intended use for the car. If they NEVER drag race and rarely dump hole shots, the IRS will serve them well, particularly when they upgrade toe links, install a bumpsteer kit and ACTUALLY bumpsteer their suspension, which is VERY important at high power levels. The higher the power level, the more important bumpsteering becomes. With upgrades like the new improved Ford Racing rear cover, failures will be fewer and farther between.

I cut my teeth open tracking and racing teeth with an IRS. There is not a single doubt it my mind the IRS makes me a better and faster driver than what I actually am. I get into my 2012 Boss 302S and I feel like I somehow forgot how to drive. I can't control the ass end of the Boss like I do my other IRS equipped cars.

FWIW

So, which one cuts better lap times?
I've always said that if I had another Cobra I would keep the IRS and put your goodies on and enjoy it. I just drag race more than anything else and the IRS wasn't doing it for me. Road manners aren't as good with the solid, but I had a fox-body before this, so it's still better than that. I need to find someone local who has the IRS and your kit to see how it feels. Even though I don't open track my car, I still enjoy spirited driving on curvy back roads.

 

[Anabolic]

irs would give you better round the track times,
SRA will give better straigh launches... allowing harder launches, and the -100lbs is another -.1 off at the track!

 

[Anabolic]

People that come to me for advice that have 700-800 RWHP and above I tell them straight out that they are pushing the limits of the IRS. (this is a relatively small group of Cobra owners) A LOT depends on their intended use for the car. If they NEVER drag race and rarely dump hole shots, the IRS will serve them well, particularly when they upgrade toe links, install a bumpsteer kit and ACTUALLY bumpsteer their suspension, which is VERY important at high power levels. The higher the power level, the more important bumpsteering becomes. With upgrades like the new improved Ford Racing rear cover, failures will be fewer and farther between.

I cut my teeth open tracking and racing teeth with an IRS. There is not a single doubt it my mind the IRS makes me a better and faster driver than what I actually am. I get into my 2012 Boss 302S and I feel like I somehow forgot how to drive. I can't control the ass end of the Boss like I do my other IRS equipped cars.

FWIW

still have to learn how to drive my car, was featyhering the throttle a few months back. the front end was going up then down then the rear was going sideways... stupid camber/bumpsteer.

 

[Shadow Grey 03]

irs would give you better round the track times,
SRA will give better straigh launches... allowing harder launches, and the -100lbs is another -.1 off at the track!

I meant between his IRS car and his new Boss.

 

[ac427cobra]

So, which one cuts better lap times?

Both cars are awesome! But it's not really a fair comparison.

My 2000 Cobra R is HIGHLY modified, it's lightened extensively, I've been driving it for 10 years and I'm VERY comfortable behind the wheel. The only piece of stock suspension on the car is the rear sway bar. It has about 450 RWHP and weighs 3,200#. I ran a 2:27 at Road America with my new aluminum block Ford GT dry sumped motor. But that was my first outing with the new motor and I really think the car honestly has a 2:25 in it or 2:26 at the minimum once I get a little more comfortable driving the car. It's quite a bit faster than the iron block wet sumped motor that went 2:28 for a best lap.

I shook down my new 2012 Boss 302S at Road America when I first got it and I had a set of old Nitto NT-01's left over from my Shelby GT500 I wanted to burn up. Lap times were slow and in the mid to high 30's getting used to the car.

After 9 years of driving three different cars at Road America, I've never had a single tire off of the racing surface. In my second session with the Boss, I went four wheels off in turn 8:

[nomedia="http://www.youtube.com/watch?v=2f-dZfmZYxE&list=UUvEx0tzjOp3kmAyAQz0w6vA&index=5&feature=plcp"]Copy of GOPR00092 trim 2 - YouTube[/nomedia]



Fortunately I wasn't going that fast but that sort of shook my confidence a bit. I'm still getting used to the car and I'm not very comfortable in it. Once I put some new slicks on the car and ran at the NASA event at Road America last October, I started getting a little more comfortable in the car. I ended up setting the American Iron track record in the first race which put me on the pole for race two with a lap of 2:32. The car is choked down 35 RWHP with a restrictor plate for American Iron competition and currently has 372 RWHP and weighs 3,535#.

Dean Martin was also at that event and for those of you that might not know Dean he's the 2009 Grand Am GS Champ and he's also the NASA American Iron NATIONAL CHAMP for the second year running. He drove my car at Road America and showed me the car was more capable than what I was driving and whacked 4 second off my record setting lap. (yeah, if he ever races there my record is history!)

Here's a video of Dean flogging my car during practice:

[nomedia="http://www.youtube.com/watch?v=HkC1APitgz8&feature=related"]Dean Martin drives my Boss 302S - YouTube[/nomedia]

:thumbsup::coolman::beer:

 

[Shadow Grey 03]

Cobra R sounds nasty from the description. Definitely cool to ride along with the best drivers out there.