Has anyone broken a 8.8 IRS? We did...

[mefarri]

So why couldn't you just make kind of a U channel out of it so it grabs on both side of the ear?

[Speedfab]

So why couldn't you just make kind of a U channel out of it so it grabs on both side of the ear?

You could, but you'd just be band-aiding something that isn't the root cause.

[Sabre002]

Damn speaking of all this I forgot to get my subframe from you Tracy.  Or are you keeping it now due to the Saturn head ake? 

[Speedfab]

I might be up to Savannah in a few weeks, we can work something that way if you want.

[largeorangefont]

Very good point.  Take a look at a photo of a 2003-04 Cobra rear setup out of the car, like here;

http://www.mpsautosalvage.com/sunshop/index.php?l=product_detail&p=2812

Most of the nose weight of the unit maybe carried by the lower mounting bracket, but the twisting motion is controlled by both the lower  and upper brackets, which work in tandum to brace the differential case and share in resisting the twisting motion, during both on and off throttle (acceleration and deceleration) loading.

The lower mount is actually an add on piece, and not part of the subframe. It attaches to the lower control arm mounts and is held by the forward LCA bolts. This was added for use in the 2003/2004 Cobras. Earlier 99 and 01 Cobras and 2000 Cobra Rs did not have this lower brace.

[DeaconBlue]

Very good point.  Take a look at a photo of a 2003-04 Cobra rear setup out of the car, like here;

http://www.mpsautosalvage.com/sunshop/index.php?l=product_detail&p=2812

Most of the nose weight of the unit maybe carried by the lower mounting bracket, but the twisting motion is controlled by both the lower  and upper brackets, which work in tandum to brace the differential case and share in resisting the twisting motion, during both on and off throttle (acceleration and deceleration) loading.

The lower mount is actually an add on piece, and not part of the subframe. It attaches to the lower control arm mounts and is held by the forward LCA bolts. This was added for use in the 2003/2004 Cobras. Earlier 99 and 01 Cobras and 2000 Cobra Rs did not have this lower brace.

So with the higher powered '03-04 Terminators, Ford apparently addressed an issue involving the high magnitude twisting/movement of the 8.8 IRS differential with the addition of this lower brace.  It would make perfect sense that with the lower powered car, the brace was not needed, but with 390 ft-lbs of torque it became necessary.  I also sent you a PM about this subject.

[Sabre002]

I might be up to Savannah in a few weeks, we can work something that way if you want.

Thats fine just let me know.  You going to be racing there or something?

[LPIRacing]

If anyone wants the Maximum motorsports piece we are a dealer.  I tore up the poly bushings as well road racing.  We made aluminum ones for it.

 

[Demon]

If anyone wants the Maximum motorsports piece we are a dealer.  I tore up the poly bushings as well road racing.  We made aluminum ones for it.

Is that all you did? How is it holding up?

[andrewb70]

Whoever is making the FD cradles needs to combine the Cobra case with an Explorer rear cover. That is what I did on the FC cradle that I used to sell. That cradle is being used in Enzo's 8 second rotary FC.

In  my opinion the front mount pictured in this thread broke because of twisting forces, not from force of the diff trying to move up. It is the same issue that causes the stock Cobra rears to shatter the rear cover when used in the Mustangs.

Andrew

[blacksi]

Hmm, I'll be checking mine out before getting on it again.  I've noticed a little bit of a new noise coming from on off acceleration.

[DeaconBlue]

Whoever is making the FD cradles needs to combine the Cobra case with an Explorer rear cover. That is what I did on the FC cradle that I used to sell. That cradle is being used in Enzo's 8 second rotary FC.

In  my opinion the front mount pictured in this thread broke because of twisting forces, not from force of the diff trying to move up. It is the same issue that causes the stock Cobra rears to shatter the rear cover when used in the Mustangs.

Andrew

Andrew, why aren't you selling the old FC cradle any more?

[mayhamfx]

You may want to make a brace that goes across the top of the 2 front diff mounts for extra support.
That broke because of the poly bushings. Use solid bushings and you will be less likely to have that problem again.

These diff housings as a rule never break in Cobras.
I have an empty Mark VIII/ Cobra aluminium center section if you want it. Shoot me a PM if you are interested.

Like this

[Rayminator]

Whoever is making the FD cradles needs to combine the Cobra case with an Explorer rear cover. That is what I did on the FC cradle that I used to sell. That cradle is being used in Enzo's 8 second rotary FC.

In  my opinion the front mount pictured in this thread broke because of twisting forces, not from force of the diff trying to move up. It is the same issue that causes the stock Cobra rears to shatter the rear cover when used in the Mustangs.

Andrew

The FD is very tight in the cover area. In fact, the stock cover mount ,is removed for clearance as I recall.

[andrewb70]

DeaconBlue,

I started to redesign the cradle to use the Explorer diffs. The Explorer case fits better in the FC and they are much more readily available and less expensive than the Cobra diffs. I never finished the project and I moved and got rid of my FC. Sort of a perfect storm of events. My original design is very strong but it required the customer to send in the rear crossmember for modification.

The builders of FD cradles need to focus on eliminating the twisting forces from breaking the front mounts on the Cobra case. The setup that Grahm posted for his FC takes care of that by distributing the load through the whole casting. The Explorer rear cover does the same thing. The front mounts on the cobra case was not designed to resist twist. Its only purpose is to control the upward motion of the front of the diff.

Andrew