The MW caps need to be bore gauged then faced off with a rod cap holding fixture. Mine were cut .028" and .025".
3.5625" dia if I remember correctly
Reinforced IRS sub-frame
- Thread starter SlowSVT
- Start date
The MW caps need to be bore gauged then faced off with a rod cap holding fixture. Mine were cut .028" and .025".
3.5625" dia if I remember correctly
+1 Awsome work buddy!!! That def. takes some time and patience not to mention skill!!!!
Let us know of any issues upon reinstalling in regard to the added bracing and tool swing radius', differential service etc. I hope all goes well.
I've had thing in and out so many times I can do it alone blindfolded. Everything has already been pre-fitted.......more than once :nonono:
I need to install this before the IRS
Installing the FTBR delrin sub-frame bushings tonight, will take pics of the install. Ring & Pinion by the end of the week. I wanna get the cover and rear mount sand blasted again before I install the diff. The guy that did it the first time blasted it with "dust" only frosting the thing when I told him I wanted it "pitted" which requires coarse media :bash:
I've had thing in and out so many times I can do it alone blindfolded. Everything has already been pre-fitted.......more than once :nonono:
I need to install this before the IRS
Installing the FTBR delrin sub-frame bushings tonight, will take pics of the install. Ring & Pinion by the end of the week. I wanna get the cover and rear mount sand blasted again before I install the diff. The guy that did it the first time blasted it with "dust" only frosting the thing when I told him I wanted it "pitted" which requires coarse media :bash:
Just be aware that the bores where the bearing and seals go need to be protected REALLY well, because the coarse blasting media such as Black Beauty, garnet, etc. will tear through most tapes and ways of masking. I would recommend pressing rubber stoppers into the pinion bore, as well as the 2 side bores, and do any blasting with the case bare (without internals), then have the gears assembled. I have been involved with sandblasting my entire life (my dad has owned a commercial sandblasting company since 1969!), and spent several years building IRS pumpkins for use in '65 Cobra replicas so I've learned a thing or 2 about the process.;-)
With regard to fitting the caps, I'm not really sure why they can't just machine them correctly (to size), because the bores where the carrier bearing races fit are all identical dimensionally. Since all machining at the factory is done in fixtures, I would assume that the bore axis centerlines could be controlled and repeatable.
I'm only blasting the cover and the mount, not the diff case itself (I made a wood cover to close off the inside of the cover and installed plastic AN thread plugs). 4 or 5 layers of duct tape usually do a good job protecting machined surfaces. Sandblast is not very effective on soft surfaces even a thick grease spot will stop it and only works on hard surfaces. I've spent more time in a blast booth then I care to relate :nonono: For a real pitted surface you got to go the guy with an industrial size blaster.
The MW caps are intentionally center offset faced to allow them to be tailored to the diff they are to be installed in. A bore gauge reading at a right angle to the parting line gives you the dimension that needs to be milled off each face. Once that's done they are interchangeable or at least the was what happened in my case.
Holy shnikies. You have more hours in your rear-end set-up than most people have in their whole cars! That's a lot of work! Thanks for the detailed posts, definitely giving me some ideas.
I've had thing in and out so many times I can do it alone blindfolded. Everything has already been pre-fitted.......more than once :nonono:
I need to install this before the IRS
Installing the FTBR delrin sub-frame bushings tonight, will take pics of the install. Ring & Pinion by the end of the week. I wanna get the cover and rear mount sand blasted again before I install the diff. The guy that did it the first time blasted it with "dust" only frosting the thing when I told him I wanted it "pitted" which requires coarse media :bash:
Glad to hear as it would really suck to begin the install only to find out tools etc. won't fit or turn. ;-)
I dont live to far from you....i would be willing to drop off my car and a lump of cash for this work....good shit...
:nonono:
Backing out of a problem is way harder than getting into it
Backing out of a problem is way harder than getting into it
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Installed the FTBR delrin sub-frame bushings............mostly
The delrin bushings just required a few taps with a rubber mallet and a block of wood
The front crush sleeves were not as cooperative
Need a 1/2' threaded rod and some nuts, thick washers with lot's of anti-seize to draw the rest of the sleeve down.
The delrin bushings just required a few taps with a rubber mallet and a block of wood
The front crush sleeves were not as cooperative
Need a 1/2' threaded rod and some nuts, thick washers with lot's of anti-seize to draw the rest of the sleeve down.
Looks fantastic
10-4 I always prefer measuring twice and test fitting. Nice work!
How much heavier is the subframe?
My attention has turned to fitting the A-arm bushings and I've added something extra to improve the action of the A-arms. This is something I was considering but what pushed me over the edge was Bruce @ FTBR stating that the bushings may squeak on the powder coat. That's something I was not aware of plus the powder coat would eventually be worn away anyhow.
The solution was to add stainless steel thrust washers to each side of the delrin bushings shown here
These are MM delrin bushing that I faced off .060" to make room for the 3" OD 316 SS washers on the left
.125" was milled off the crush sleeve
You can see in this photo the mill removed much of the chamfer in the MM bushings. This increases the thrust bearing surface area and where it will do the most good :rockon:
When you drill for the grease fitting make sure you locate the hole in the gap between the ends of the bushing to ensure the grease can actually get distributed where it's needed. I have Prothane grease in a grease gun to lubricate the A-arms. The stuff is very stiff and won't "flow" like petroleum grease
Where you see silver in this photo shows the additional thrust bearing surface that has been achieved. This will take-up some of the lateral loads on the crush sleeve and help locate the wheel more accurately.
I'm a tad tight on one side of the front bushings and need to shave .010-.020" off to get the thrust washer to side between the bushing and the ear.
I think you guys should hound Bruce "incessantly" to offer this with his delrin A-arm bushingsoke:
The solution was to add stainless steel thrust washers to each side of the delrin bushings shown here
These are MM delrin bushing that I faced off .060" to make room for the 3" OD 316 SS washers on the left
.125" was milled off the crush sleeve
You can see in this photo the mill removed much of the chamfer in the MM bushings. This increases the thrust bearing surface area and where it will do the most good :rockon:
When you drill for the grease fitting make sure you locate the hole in the gap between the ends of the bushing to ensure the grease can actually get distributed where it's needed. I have Prothane grease in a grease gun to lubricate the A-arms. The stuff is very stiff and won't "flow" like petroleum grease
Where you see silver in this photo shows the additional thrust bearing surface that has been achieved. This will take-up some of the lateral loads on the crush sleeve and help locate the wheel more accurately.
I'm a tad tight on one side of the front bushings and need to shave .010-.020" off to get the thrust washer to side between the bushing and the ear.
I think you guys should hound Bruce "incessantly" to offer this with his delrin A-arm bushings
oke:
I would estimate about 10 lbs.
So did you wake up one day and was like "I feel like welding reenforcement tothe IRS, could be fun right?"
Looks good man!
Looks good man!
More like "the car demanded it!"
did I say how much I hate chassis work? :cuss:
The finished results are "fun"
Here is an update on my progress
I deepened the camber adjustment slot about .045 to accept the FTBR eccentric caster adjustment bolt which should allow up to 2 degrees of negative camber. And I milled the upper A-arm delrin bushings and crush sleeves to accept the stainless thrust washers. The bushings held in place using Goop glue to prevent them from turning in the bores and not on the crush sleeve.
Here is the upper A-arm installed in the sub-frame with the SS thrust washers. Now both the upper & lower A-arms are captured on 3 sides and not just on the crush sleeve.
I needed to expand and parallel the A-arm pivot ears slightly
Here is the lower diff support. Hard to see in this photo but there was a filler plate welded over an opening on the mounting bracket. This one escaped powder coat.......for now.
Eibach rear sway bar added to the mix
This photo shows the 6 point IRS sub-frame brackets for attaching the to the upper SRA control arm mounts.
Here is a neat trick that gets overlooked.
Aftermarket extended wheel stud lack the shoulder found of the OEM studs. I tapped a .562 OD x .500 ID SS tube to the flange which gets the disc to fit nice and snug on the hub and not rock back & forth on the studs. I don't think this is a real big deal but better to have it then "not"
Waiting to get the diff back from shimming and checking. I have the crew chief from BMR racing team go thru the whole diff. Here is Doug Robinson who is the main builder of their race cars. There is a centrifugal supercharged 426 hemi stuffed under the bonnet. I think this thing will do 250. When I need advice he's the guy I go to. His work is incredible! :rockon:
I deepened the camber adjustment slot about .045 to accept the FTBR eccentric caster adjustment bolt which should allow up to 2 degrees of negative camber. And I milled the upper A-arm delrin bushings and crush sleeves to accept the stainless thrust washers. The bushings held in place using Goop glue to prevent them from turning in the bores and not on the crush sleeve.
Here is the upper A-arm installed in the sub-frame with the SS thrust washers. Now both the upper & lower A-arms are captured on 3 sides and not just on the crush sleeve.
I needed to expand and parallel the A-arm pivot ears slightly
Here is the lower diff support. Hard to see in this photo but there was a filler plate welded over an opening on the mounting bracket. This one escaped powder coat.......for now.
Eibach rear sway bar added to the mix
This photo shows the 6 point IRS sub-frame brackets for attaching the to the upper SRA control arm mounts.
Here is a neat trick that gets overlooked.
Aftermarket extended wheel stud lack the shoulder found of the OEM studs. I tapped a .562 OD x .500 ID SS tube to the flange which gets the disc to fit nice and snug on the hub and not rock back & forth on the studs. I don't think this is a real big deal but better to have it then "not"
Waiting to get the diff back from shimming and checking. I have the crew chief from BMR racing team go thru the whole diff. Here is Doug Robinson who is the main builder of their race cars. There is a centrifugal supercharged 426 hemi stuffed under the bonnet. I think this thing will do 250. When I need advice he's the guy I go to. His work is incredible! :rockon:
I have been reading this since it started and I have to ask why? Is there something i missed that the stock irs cradle is not strong enough? Did you ever get to test the themostat?
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