Cobra IRS Delrin control arm bushings

[ac427cobra]

Comments on the bushings -
Having worked on a set of "Brand N" myself, and having seen the installation of those from Bruce & co. I can say that the units from Bruce are superior. While I don't have a massive amount of "bushing experience", Terry has done many, and made the following 2 statements:
"I've never installed a set of bushings that fit this well out of the box"
and
"There's not many performance parts I'd say this about, but I don't really see anywhere for improvement with these bushings"

IMO - anyone reading this looking for an all-out handling IRS and considering bushings - don't waste time and money on anything else. Yes these are a bit spendy, but they are no compromise units and well worth the investment.


Don

Don:

I quoted my favorite part of your post! epper: Thank you for the kind words. It is very nice to hear. Ken and I appreciate it very much.

I guess the 26 years I have had my business has helped. We take OEM parts and redesign them so they work! ;-) They are from a completely different industry, but the same principals apply.

Machining plastic, Delrin in particular, can be an art form. That's where Ken comes in. :-D Anybody can machine plastic, but knowing what you're doing when machining it, is the hard part. Ken knows what he's doing. :bowdown:

When I first discussed the design of the prototype parts with Ken he assured me he could hold very tight tolerances on the materials. The parts I received from him were spot on. That makes installation a breeze.

The price of this complete kit might sound like a lot of money. That is until you price the IRS kit from Maximum Motorsports. The Brand "N" kit might be less :nono: but let's not go there!? ;-)

Please recognize Delrin is a very durable yet expensive material. Labor rates in machine shops with modern equipment are no small part of the equation. Ken and I are not making a lot of money on these parts I can assure you. We are basically providing a service to fill the void in the marketplace. We will continue to offer these components as long as there is demand for them. We are striving to have the best kit available for the money with the best fitting and least amount of assembly hassles. I think we're close! :-D

We appreciate any and all comments. I will assist in any way I can. Unlike Brand "N" bushings where the communication stops upon payment. It's not like that buying our bushings. I'm a PM away!

Thank you again for the positive comments!

Bruce

:thumbsup: :coolman: :beer:

 

[johnny-longtors]

Nothing says quality like a banana riding a llama!

 

[Jimmysidecarr]

Nothing says quality like a banana riding a llama!

:lol: I almost woke the wifey up!!!

Great write up Don...

Very few doubts before ... ZERO now... Brand B for me.. hope to be ordering soon... most likely June.

:banana: oke: :bowdown:

 

[hatsharpener]

So, I finally got around to actually putting the cradle in the car -- yeah, it's taken me that long (I'm slow!). The front bushings went into the torque boxes (which were welded up prior to install) very snug. I did have an issue with the rear mounts for the cradle being about 1/8" off now. I just loosened the rear bracket and slid it forward a ways. I needed to apply a few love taps from the 3lb hammer to get the rear cradle bushings in place. Tightened everything up, installed the BF IRS brackets.

I also welded an 1/8" thick piece of sheet along the back of the rear bracket for extra support (about 3" long and 1.5" wide) between the cantilevered edge and the bracket. I'll throw up a picture after I get them off of the camera. It doesn't interfere with the removal or installation of the cradle and it should add a little more support to the bracket.

Are all IRS braces the same, or is there one that's better than others? I need to pick up one before the pumpkin goes back in.

 

[johnny-longtors]

Are all IRS braces the same, or is there one that's better than others? I need to pick up one before the pumpkin goes back in.

If you want to pay homage to the inventor you'll buy it from Billetflow. The Steeda unit has a couple more gussets, but it's been argued that they are superfluous. The Steeda unit is also "naked" as opposed to the BF units which are nicely powder coated.

 

[03'Darin]

I put the BF on mine. EXCELLANT quality and very stout!! One of the two spare IRS rears I have came with a diff brace on it. I don't know who's brace it is, but it's a cheap flimsy looking piece of junk yard steel.

Darin

 

[SGL]

I don't know who's brace it is, but it's a cheap flimsy looking piece of junk yard steel.

Darin

I don't know which one this may be but I can vouch for the "stoutness" of the steeda part. It's stout alright.

 

[SGL]

The Steeda unit is also "naked" as opposed to the BF units which are nicely powder coated.

I don't know about that. Mine came with what looks like a zinc-dichromate coating. That should withstand several hundred hours of salt spray exposure. I pulled the diff out recently and after two years of usage, the brace looks brand new.

 

[hatsharpener]

If you want to pay homage to the inventor you'll buy it from Billetflow. The Steeda unit has a couple more gussets, but it's been argued that they are superfluous. The Steeda unit is also "naked" as opposed to the BF units which are nicely powder coated.

Sorry, I wasn't referring to the IRS brace. Late-night type-o on my part. I was referring to the pinion support brace. My bad.

 

[hatsharpener]

Here's a picture of the bracket that was added.

 

[ac427cobra]

Lee:

Do you have something (like an angle also secured to the trunk floor?) on the other side (inside) of that bracket?

 

[hatsharpener]

Lee:

Do you have something (like an angle also secured to the trunk floor?) on the other side (inside) of that bracket?

For the bottom brace, no, we did not (I am not yet the proud owner of a welder, hence the we). We thought about it when we were doing that, but that would make the bracket more difficult to remove in the future. The thought was that that little brace would help preven some flexing.

I will have to remove the brackets in the future if I am ever going to remove those bolts holding the cradle in the rear. Apparently they don't like being torqued down to spec. I may do that anyways as I don't know if I really like the idea of having the rounded head bolt there and just don't worry about the extra 1/4-1/2" of clearance.

If you are talking about the top bracket (the Mathis bracket) with the 3 bolts, then yes. Those are from billetflow and they secure to the inside of the trunk with another piece of metal.

 

[ac427cobra]

I was referring to the upper portion. I'm not sure how much support that inner wheelhouse is giving you with that additional upper bracket without something backing it up on the other side?

I like what you've done with that lower brace you put on there.

:thumbsup: :coolman: :beer:

 

[LargeOrangeFont]

I was referring to the upper portion. I'm not sure how much support that inner wheelhouse is giving you with that additional upper bracket without something backing it up on the other side?

I like what you've done with that lower brace you put on there.

:thumbsup: :coolman: :beer:

Are you gaining anything from the lower brace piece when using the UHMW cradle bushings?

I was going to add a brace just like that after installing the UHMW bushings. After observing how solidly the UHMW bushings mount when you tighten the rear IRS bolt through the steel sleeve I reconsidered. I don't know if you gain any strength, but it can't hurt. I can definately see how such a brace would be an improvement when using urethane bushings.

Looks great!

Ashley

 

[ac427cobra]

Are you gaining anything from the lower brace piece when using the UHMW cradle bushings?

I was going to add a brace just like that after installing the UHMW bushings. After observing how solidly the UHMW bushings mount when you tighten the rear IRS bolt through the steel sleeve I reconsidered. I don't know if you gain any strength, but it can't hurt. I can definately see how such a brace would be an improvement when using urethane bushings.

Looks great!

Ashley

IMHO anything you can do to stiffen up that rear cantilevered mount will help. Regardless of what bushing is being used.

:thumbsup: :coolman: :beer:

 

[MidLifeC]

The cantilever bracket is pretty strong by itself. When I installed my 'new' IRS assembly the rear poly bushings hung up in the bracket. Lifting the IRS cradle with a jack lifted the rear of my car off a 2 post lift. The brackets did not budge, but my car was slowly tilting forward as we lifted the cradle. I had to unbolt my cantilever support from inside the trunk and spread the cantilever mount with a BF pry bar before the car dropped down on the cradle. <I never want to go through that again>.

 

[hatsharpener]

I was referring to the upper portion. I'm not sure how much support that inner wheelhouse is giving you with that additional upper bracket without something backing it up on the other side?

I like what you've done with that lower brace you put on there.

:thumbsup: :coolman: :beer:

Here's the back of the brace from inside of the trunk.

The cantilever bracket is pretty strong by itself. When I installed my 'new' IRS assembly the rear poly bushings hung up in the bracket. Lifting the IRS cradle with a jack lifted the rear of my car off a 2 post lift. The brackets did not budge, but my car was slowly tilting forward as we lifted the cradle.

I ended up going through the same thing only my car is on 4 jackstands.

 

[JorgeG]

well the uhmw bushings are in the cradle, and the cradle was lifted onto the mount!. Following the instructions made it easier than the first time i did it. took about an hour to align everthing. Ran out of daylight so hopefully tomorrow the bolts will be torqued.
thanks bruce

 

[93cobra#3326]

subscribing :beer:

 

[BlackBolt9]

I know there was discussion as to a different material to use for the front diff spacers. I talked with my material guy and he got me some G-11. Its a glass filled phenolic that is supposed to hold its mechanical strength at higher temperatures. It is also self extinguishing which is always a plus in those rare cases of fire. If someone is interested in trying this I have enough material to produce a couple sets if someone is interested in trying them. Let me know what you guys think.