Ready To Pull The Trigger on 8.8 SRA - Advice Needed

[vip3r1850]

So I am ready to purchase a SRA for my 03. Done all my research (or so I think), and just wanted to run it by everyone in case they think I may have a problem.

This is more of a strip than street car with occasional street use but I want to retain ABS so it will remain with 8.8 ends on it.

Parts List:

94-98 Powdercoated Housing w/ Quad Shock Brackets Removed - From my understanding fits better than a 99-04 with drag wheels etc.
33 Spline Moser Wavetrac - Not interested in a spool. This appears to be the best differential available.
33 Spline Moser Custom Axles - 5.75" Flange for future Baer SS4 Rear Brake Upgrade.
C-Clip Eliminators
FRPP 3.27 Gears
GT Caliper Brackets & Backing Plates - Staying with GT Caliper Brackets and Smaller Rotors, Will Reuse COBRA Calipers - Doing this so I can use 15" wheels without cutting and grinding anything
GT ABS lines etc ...
GT Pinion Flange

Also open to ideas for LCAs and UCAs, was just going to go with UPR.

This is all mated to a Rossler Th400

Thanks everyone !

 

[Swervedriver]

I personally have used, and do not like C clip eliminators. They are very prone to leakage and the bearings have a pretty short life if subjected to street use.

You say you plan to retain rear ABS but you don't mention Reluctor wheels. This is very important. The stock SN96 axles are likely going to be smaller in diameter than the mosers, and an eliminator axle has a big bearing block hanging off the axle flange. I'm not sure right off the top of my head what the best approach to getting a reluctor wheel on there would be but I imagine it could take a custom bearing with a wide inner race to space the reluctor wheel, a machined neck on the axle for the reluctor wheel, and that's assuming there is enough space with the big eliminator bearing block hanging off the flange.

I was able to run 15X10" centerline telestar wheels with Cobra brakes, rotors, and lines but wheel backspace is critical. GT brakes do make it easier.

Rather than putting a GT pinion flange & U joint on it I'd suggest putting a Cobra 1350 Pinion flange on the diff and using 1350 to 1350 U joints all the way through.

Are you wanting to run stock location coil springs?

I happen to have a set of springs, an airbag (lost the shrader valve though), and some clipped springs just sitting in my garage. I also have a Cobra 8.8 pinion flange & 1350 rear driveshaft yoke. LMK if you'd be interested in them, although honestly I'd recommend the UPR stock location 2.5" adjustable coil spring setup and some good shocks. I dig double adjustable Afcos.

What about a diff cover/girdle?
Mark williams carrier cap?
ARP carrier cap studs?
RATECH pinion spacer?
What about a diff axle tube brace?
I and several other have gone through having tubes welded only to break the welds. I ended up throwing my housing away after dumping $750 into having it straightened, re-welded, and pinned only to break the weld again and shift hard on me making a pass.

8.8s are great diffs but once a tube moves on you things can get REALLY frustrating. Search for my 9" thread in this section. It shouldn't be too far down.

 

[sav03cobra]

Here is a picture and set-up of mine:

Details of new SRA:

SN95 Axle - 98 Mustang
Sand Blasted and Powder Coated (Blue)
Welded Tubes
31 Spline Auburn Diff
Ford Racing 3.73s
31 Spline Yukon HD Rear axles
TA Diff cover
ARP Studs
Ford Racing Bearings and seals.

Not pictured: HPM Megabite UCA and LCAs.

 

[sav03cobra]

Very true, my other set-up included c-clip elims. I absolutely hated them, had to change out the bearings and seals every six months. They do not handle street driving at all.

 

[vip3r1850]

I personally have used, and do not like C clip eliminators. They are very prone to leakage and the bearings have a pretty short life if subjected to street use.

You say you plan to retain rear ABS but you don't mention Reluctor wheels. This is very important. The stock SN96 axles are likely going to be smaller in diameter than the mosers, and an eliminator axle has a big bearing block hanging off the axle flange. I'm not sure right off the top of my head what the best approach to getting a reluctor wheel on there would be but I imagine it could take a custom bearing with a wide inner race to space the reluctor wheel, a machined neck on the axle for the reluctor wheel, and that's assuming there is enough space with the big eliminator bearing block hanging off the flange.

I was able to run 15X10" centerline telestar wheels with Cobra brakes, rotors, and lines but wheel backspace is critical. GT brakes do make it easier.

Rather than putting a GT pinion flange & U joint on it I'd suggest putting a Cobra 1350 Pinion flange on the diff and using 1350 to 1350 U joints all the way through.

Are you wanting to run stock location coil springs?

I happen to have a set of springs, an airbag (lost the shrader valve though), and some clipped springs just sitting in my garage. I also have a Cobra 8.8 pinion flange & 1350 rear driveshaft yoke. LMK if you'd be interested in them, although honestly I'd recommend the UPR stock location 2.5" adjustable coil spring setup and some good shocks. I dig double adjustable Afcos.

What about a diff cover/girdle?
Mark williams carrier cap?
ARP carrier cap studs?
RATECH pinion spacer?
What about a diff axle tube brace?
I and several other have gone through having tubes welded only to break the welds. I ended up throwing my housing away after dumping $750 into having it straightened, re-welded, and pinned only to break the weld again and shift hard on me making a pass.

8.8s are great diffs but once a tube moves on you things can get REALLY frustrating. Search for my 9" thread in this section. It shouldn't be too far down.

Thanks for your input ! And here I thought I had most of it figured out . . .

I did read about some people complaining about leaking C-Clip Eliminators and the bearings wearing out but it seems subjective as there are plenty of folks who claim a lot of street mileage (I guess it also depends on condition of road surface) so I was not completely turned away from using them.

Regarding the reluctor wheel I assumed that they builder knew about it since they quoted everything (w/ ABS) - I better call and make sure . . .

Yes you can definetly run some 15" wheels and I believe the backspace needs to be no more than 5.5" as @ 6.5" it seems most wheels do hit the banjo bolt etc.

I meant to write 1350 pinion flange but for some reason I wrote GT ! So yes, it would be a 1350 pinion flange.

I was going to go with the UPR drag spring and Viking Double Adjustables. Basically a better QA1.

Skeptical on doing coil overs in the stock location due to the thin sheet metal. An option was either FB or CHE tower brace thats welded to the tower and the floor pan but I'm not 100% sold on that solution.

Was going to go with a T/A cover. I did not consider ARP studs or a Ratech pinion spacer.

Was going to do a simple UPR brace.

Do a SRA swap they said . . . It will be easy they said . . . NOT

 

[vip3r1850]

Here is a picture and set-up of mine:

Details of new SRA:

SN95 Axle - 98 Mustang
Sand Blasted and Powder Coated (Blue)
Welded Tubes
31 Spline Auburn Diff
Ford Racing 3.73s
31 Spline Yukon HD Rear axles
TA Diff cover
ARP Studs
Ford Racing Bearings and seals.

Not pictured: HPM Megabite UCA and LCAs.

Nice. Did you keep your ABS ? I assume 8.8 ends ? Power level ?

 

[Swervedriver]

Skeptical on doing coil overs in the stock location due to the thin sheet metal. An option was either FB or CHE tower brace thats welded to the tower and the floor pan but I'm not 100% sold on that solution.

I wasn't talking about stock shock location coilovers, I was talking about 2.5" coilover springs in the stock LCA location.

The stock spring is 2.5" at the LCA then opens up to some large size that I've never bothered to measure up at the frame rail. UPR sells an upper mount. Cut out the stock mount, weld in the UPR mount, stick a "coilover" spring in that location and adjust the upper mount to desired ride height (then measure lip height with driver weight, then measure cross weight and size to side weight, then corner balance... )

79-04 Mustang Adjustable Rear Spring Mount & Springs

I tried the UPR rear coilovers and they didn't work. I probably could have tried a bunch of spring rates to find the right setup but just sold them since the lakewood shocks would have limited me anyhow and went with afcos in the stock location with coilover springs. I know quite well about how the shock towers weren't designed to hold the cars weight so I welded all of the seams and added a shock tower mount that I made from brackets and a bar.

My intention was to make some shakedown passes and finish that bar with supports going from the bottom of my brackets up to near the center of the main bar. Trans case cracked and started pushing fluid on my last pass so I've been a bit distracted from the rear shock tower bar... :fm:

Your mention of shock tower seams not holding up reminds me of the factory torque box weaknesses. You really need to weld up all the seams on the UCA and LCA torqueboxes. It wouldn't be a bad idea to also install UPR "battle boxes" (you know, since you're going to have the diff out of the car...) but don't stop there. There is still a single spot weld on the forward inner corner of the upper torque box that goes into the ridiculously thin floor pan. Go ahead and weld up as much of that seam as you can, then put a strap over it tieing to the large rear baby seat bolt down bracket.

Here are pics of mine to give you a better picture of what I'm talking about.

I did the above out of necessity. I started pulling both UTBs right out of the floor pan with simple foot braking 1.50 60' on slicks. Although it may have started back when I was trying to destroy my cars pussy with a Spec V clutch, T56, & 325 M&H drag radials. :bash:

Do a SRA swap they said . . . It will be easy they said . . . NOT

Heh yeah it can be as easy as bolting in an all stock 28 spline SRA but it'll wheel hop just like the IRS without quad shocks and won't be any stronger.

Which reminds me. Since you're deleting quad shocks, be sure to do all solid bushings and heim joints. No rubber. Delrin will work but you'll just en up ripping open the thin metal around the delrin. My suggestion would be UPR "extreme" UCAs. These are the LCAs I ran before I went double heim joint LCAs with the 9" (they're still sitting in my shop bay).

Since you've got a TH400 I'm assuming it's trans braked and will be hitting the tires pretty hard. Better to get everything ready for it now than to go back in later like I have done.

 

[sav03cobra]

Nice. Did you keep your ABS ? I assume 8.8 ends ? Power level ?

I did not chose to keep ABS, my car on street boost is around 19lbs seeing about 650hp+ 640tq+.

Yes 8.8 ends.

 

[vip3r1850]

I wasn't talking about stock shock location coilovers, I was talking about 2.5" coilover springs in the stock LCA location.

The stock spring is 2.5" at the LCA then opens up to some large size that I've never bothered to measure up at the frame rail. UPR sells an upper mount. Cut out the stock mount, weld in the UPR mount, stick a "coilover" spring in that location and adjust the upper mount to desired ride height (then measure lip height with driver weight, then measure cross weight and size to side weight, then corner balance... )

79-04 Mustang Adjustable Rear Spring Mount & Springs

I tried the UPR rear coilovers and they didn't work. I probably could have tried a bunch of spring rates to find the right setup but just sold them since the lakewood shocks would have limited me anyhow and went with afcos in the stock location with coilover springs. I know quite well about how the shock towers weren't designed to hold the cars weight so I welded all of the seams and added a shock tower mount that I made from brackets and a bar.

My intention was to make some shakedown passes and finish that bar with supports going from the bottom of my brackets up to near the center of the main bar. Trans case cracked and started pushing fluid on my last pass so I've been a bit distracted from the rear shock tower bar... :fm:

Your mention of shock tower seams not holding up reminds me of the factory torque box weaknesses. You really need to weld up all the seams on the UCA and LCA torqueboxes. It wouldn't be a bad idea to also install UPR "battle boxes" (you know, since you're going to have the diff out of the car...) but don't stop there. There is still a single spot weld on the forward inner corner of the upper torque box that goes into the ridiculously thin floor pan. Go ahead and weld up as much of that seam as you can, then put a strap over it tieing to the large rear baby seat bolt down bracket.

Here are pics of mine to give you a better picture of what I'm talking about.

I did the above out of necessity. I started pulling both UTBs right out of the floor pan with simple foot braking 1.50 60' on slicks. Although it may have started back when I was trying to destroy my cars pussy with a Spec V clutch, T56, & 325 M&H drag radials. :bash:

Heh yeah it can be as easy as bolting in an all stock 28 spline SRA but it'll wheel hop just like the IRS without quad shocks and won't be any stronger.

Which reminds me. Since you're deleting quad shocks, be sure to do all solid bushings and heim joints. No rubber. Delrin will work but you'll just en up ripping open the thin metal around the delrin. My suggestion would be UPR "extreme" UCAs. These are the LCAs I ran before I went double heim joint LCAs with the 9" (they're still sitting in my shop bay).

Since you've got a TH400 I'm assuming it's trans braked and will be hitting the tires pretty hard. Better to get everything ready for it now than to go back in later like I have done.

Thanks for all the info. I definitely knew about the torque boxes. I was going to go with the wild rides version. Was definitely not going to put the SRA in there without them. Im not sure i want to go metal on metal with the control arms. I don't want to deal with clankity clank clank all the time. Do you have pictures of your ripped up bushings ?

 

[Swervedriver]

I never ripped up bushings but I've seen delrin bushed UCAs rip open the strap before. First time I saw it was on a friends high 11 second SRA swapped '99 Cobra. Read: Barely over 300rwhp but hit the tires as hard as he could...

I ran UPR heim joint Radius rods for a while and started pulling the heim joints open. I could tell something was getting sloppy because the "clank clank" on & off throttle when cruising was getting worse & worse. I thought the torque boxes were opening up but fortunately it was just the Heim joints.

After that I went to UPR Extreme for a brief period. Jigged, Straightened, re-welded, and pinned axle tubes broke free from the housing on the first flippn pass. I tried driving through it for about 15 passes or so before losing my patience with it and swapping in the 9". Hard to launch a car that's torque steering worse than a stock IRS. I did cut a couple of decent 1.46 60' but as soon as the front tires touched down it would steer right at the wall. Driving from that point to just past the 8th was like driving a 700rwhp skid steer.

 

[1loudmouthpony]

I used a 95 8.8 rear they are 1.5 inch narrower than the 99-04 sra.

j&m uppers and lowers (for now)
3.73 gears stock differential and axles (for now)

made a few passes at the strip seemed to hold up.

One thing I failed to notice was the pinion flange for the drive shaft on my 95 rear will not work for the flange for the cobra drive shaft. you will need to switch them over, OR buy a special U joint that fits the 95 gt flange to the driveshaft on this application. so bascially im using a cobra drive shaft but with the 95 gt ds and pinion flange. I will take care of this soon as the gt flange was much smaller than the cobra's.



Ill be selling my magna pack catback for a 8.8 its got maybe 1500 miles on it if your interested. going back to flowmasters.

good luck, for my purpose I wish I would have kept it but in my case it was either spend 1000+ to find a new differential housing or use this rear I have now.

 

[Swervedriver]

^ Cobras use 1350 U joints and GTs as well as Machs use 1320.

I Have a cobra pinion flange and rear driveshaft yoke in my shop bay too with 12 point ford bolts.

 

[1loudmouthpony]

^ Cobras use 1350 U joints and GTs as well as Machs use 1320.

I Have a cobra pinion flange and rear driveshaft yoke in my shop bay too with 12 point ford bolts.

I had to use a u joint that on one joint used the 1350 length and the other used the 1320 length they were not the same length, ill dig the box out and try to find a part number.

 

[Swervedriver]

Yeah those adapter U joints aren't uncommon. GM used them on several of their trucks that didn't have the big motor, but did have the big diff. Go into a parts store and try to get a U joint for a GM truck just by vehicle description. LOL

 

[BlckBox04]

just curious why you're using 3:27 gears with a stock t56. Im getting ready to put my solid in too and previous owner had 4:56 but that's too short of a gear and don't know if I should go 3:73