Thinking about a 99 or newer cobra. I want to put a vortech on there. I know for drag racing, I need a solid rear. What about daily driving and autocrossing?
How much HP/Torque can IRS stand?
- Thread starter TRY2PAZ
- Start date
Really depends on the launch.
99s: I've heard of stock cars breaking half shafts. A friend of mine is pulling 1.9s on DRs, running a Novi1000'd 460rwhp through his stock IRS (4.30 gears) and never had a problem. Another friend was running a customers 99 Cobra / 100shot nitrous and pulled a 1.6 60ft and broke the halfshaft on the 1-2shift.
2001s have 31 spline axles vs the 28s on the 99s, and I've haven't heard of half shafts breaking on 2001s yet.
Either way, the IRS isn't a drag racing suspension. Severe wheel hop and small half shafts don't make for good launches. An 8.8 will swap right in there
99s: I've heard of stock cars breaking half shafts. A friend of mine is pulling 1.9s on DRs, running a Novi1000'd 460rwhp through his stock IRS (4.30 gears) and never had a problem. Another friend was running a customers 99 Cobra / 100shot nitrous and pulled a 1.6 60ft and broke the halfshaft on the 1-2shift.
2001s have 31 spline axles vs the 28s on the 99s, and I've haven't heard of half shafts breaking on 2001s yet.
Either way, the IRS isn't a drag racing suspension. Severe wheel hop and small half shafts don't make for good launches. An 8.8 will swap right in there
yup yup. what Matt said.
Tahnks Matt
Our '01s aren't breaking their half-shafts, but the tranny's are going. I've heard of 4 '01s that have already blown through 2nd on a hard shift.
-Matt
-Matt
Guy in our club has broken 2nd gear in his 2001.
Get this, when they ordered the replacement, a T45 came instead of the 3650. So they installed the T45 for the time being.... lmao.
With all I've heard, he might wanna keep it
Get this, when they ordered the replacement, a T45 came instead of the 3650. So they installed the T45 for the time being.... lmao.
With all I've heard, he might wanna keep it
So I guess the T-45 is better than the 3650? That what comes in the 01 cobra's right?
yup, 01's are having tranny problems and pinging problems.
As far as the half-shafts, sorry to break it to you guys...but 31spline vs. 28spline doesn't make a damn of a difference.
People who have broken the cobra IRS all break them in the same place...the CV joints. Whether the inner or outer CV joint, that's the weak spot...not the half-shaft itself. However, CVJ's are part of the half-shaft assembly, so "i broke a half-shaft" is true, but misleading.
I think once people with 01's start running juice, running blowers, running more passes at the track, and adding more mods...we'll see the same type of IRS failure.
As far as the half-shafts, sorry to break it to you guys...but 31spline vs. 28spline doesn't make a damn of a difference.
People who have broken the cobra IRS all break them in the same place...the CV joints. Whether the inner or outer CV joint, that's the weak spot...not the half-shaft itself. However, CVJ's are part of the half-shaft assembly, so "i broke a half-shaft" is true, but misleading.
I think once people with 01's start running juice, running blowers, running more passes at the track, and adding more mods...we'll see the same type of IRS failure.
Believe me, I'm not saying the T45 is in anyway better, but the 3650 hasn't lived up tp it's hope of being a stronger tranny, just alot smoother... hint to Ford T-56 T-56 T-56
As for the half shafts, I haven't heard of any 2001s breaking yet, but like Redlyne said, they break at the CJ joints. The splines have nothing to do with that.
Yes 2001 Cobras have the Tremec 3650 tranny.
As for the half shafts, I haven't heard of any 2001s breaking yet, but like Redlyne said, they break at the CJ joints. The splines have nothing to do with that.
Yes 2001 Cobras have the Tremec 3650 tranny.
i know that the 3650 is smoother, and i love having a synchronized reverse (no more grinding when backing out of the driveway!).
But COME ON FORD! GIVE US THE T 56! it can't cost THAT much more.
As for the number of splines, on our stock half shafts, it makes no difference, because the higher number of splines just reduces the chance of the splines stripping by distributing the load over a greater number of splines. but apparently the CV joints go south way before that point, so it doesn't really even matter.
makes me wonder, could they have just left the old half shafts, taken all the saved money from testing and new parts, and UPGRADED OUR FRIGGIN TRANNY TO A T 56!?!?!?
But COME ON FORD! GIVE US THE T 56! it can't cost THAT much more.
As for the number of splines, on our stock half shafts, it makes no difference, because the higher number of splines just reduces the chance of the splines stripping by distributing the load over a greater number of splines. but apparently the CV joints go south way before that point, so it doesn't really even matter.
makes me wonder, could they have just left the old half shafts, taken all the saved money from testing and new parts, and UPGRADED OUR FRIGGIN TRANNY TO A T 56!?!?!?
I am one of those people who blew my tranny. It just happened during a burnout, so i almost sh!t my pants. The dealer knows about my gears, and I was woried that they would deny my warranty. They didn't, and ordered me a new tranny today. How can I tell when i get my car back if they put the Tremmec of the T-45 back in?
Most likely you will get a 3650, since you have an 01. Ask the dealer for a 99 T-45 tranny. It wont hurt to ask.
Its not true that they'll give you a 3650 because you have a 2001. I just got mine back this monday after 3 weeks in service for a clutch problem and they ended up changing my tranny also. They said my pressure plate destroyed my clutch. Anyway, they gave me a T-45 and a lighter feeling clutch. I'm not really a big fan of the new set-up, but I'm getting used to it. I already told the service manager that if I dont like it I want it redone. He agreed. We'll see what happens.
hey svtsnake-
off topic, but where did you get your black letters? I have seen the stainless steel ones....but not the black ones (for the new cobra bumpers).
off topic, but where did you get your black letters? I have seen the stainless steel ones....but not the black ones (for the new cobra bumpers).
There is a huge shortage of 3650s. They even discontinued manual GTs for the rest of the year.
Mine seems pretty strong right now. I do beat on it and it hasn't given out.
I do get a really bad vibration out of the tranny in 4th gear at redline. It literally vibrates the shifter to the point that it hurts. I don't know what to make of that.
I'll have them take a look at that when I go in for the shifter fork TSB.
-Matt
Mine seems pretty strong right now. I do beat on it and it hasn't given out.
I do get a really bad vibration out of the tranny in 4th gear at redline. It literally vibrates the shifter to the point that it hurts. I don't know what to make of that.
I'll have them take a look at that when I go in for the shifter fork TSB.
-Matt
yup, since buying my '01, i've been reading the reviews and now i'm a little weary of attempting a burnout. i have no desire to shred my 2nd gear. i'm already getting some notchiness with my 2-3 shift. not good.
i totally agree with the guy earlier who posted about a t56. i was thinking about swapping out the tremec in favor of this tranny.
i totally agree with the guy earlier who posted about a t56. i was thinking about swapping out the tremec in favor of this tranny.
I would get a Stick for the rear and put some of that Slick 50 in either one of those trannys. And hold on to your A?s. I'm on my 3rd T-45. So don't feel bad..
More power = more Whobbles for the IRS. I'm running 441rwhp detuned from 498hp with Griggs suspension
Just a cheap design from Ford. Bastards..
I have some video you can check out. Car ran 13.50 112mph
You can hear the wheel hop. That was the biggest problem. Can't launch the car.
Drag Video
Website
More power = more Whobbles for the IRS. I'm running 441rwhp detuned from 498hp with Griggs suspension
Just a cheap design from Ford. Bastards..
I have some video you can check out. Car ran 13.50 112mph
You can hear the wheel hop. That was the biggest problem. Can't launch the car.
Drag Video
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The part of all of this that burns my @$$ is that We paid for a performance car.
A NOTE TO FORD - A performance car isn't a performance car if you have to baby it. We want a hell for stout, rock solid design that can stand up to a little rough handling. You guys are bound and determined to make a GM guy out of me yet......good thing for you they are discontinuing the F body.
Why buy a performance car if you can't drive it hard? Kind of like a Lab that does not like the water!
A NOTE TO FORD - A performance car isn't a performance car if you have to baby it. We want a hell for stout, rock solid design that can stand up to a little rough handling. You guys are bound and determined to make a GM guy out of me yet......good thing for you they are discontinuing the F body.
Why buy a performance car if you can't drive it hard? Kind of like a Lab that does not like the water!
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