http://ls1tech.com/forums/suspension-brakes/1461797-indepedent-rear-suspension-irs-4th-gen.html

Hello to all Members,

I want to introduce myself and my company to you. Since I've been a member for over a year, I think everything is in place to do an intro.

I have a small company, JH Engineering, that manufactures brake kits for the venerable Jag IRS along with other services. jheengineering.com

With the exit of Mike Bontoft at C.W.I., it left a definite void for the Jag IRS enthusiast. I don't/won't ever claim to be on a level with Mike. He probably wouldn't remember me...I bought a couple of IRSs from him back in the late '70s when he had his shop in Costa Mesa, CA. to start my courtship with the Jag.

All I want to say and do is to provide the Jag enthusiast some great brake products that have been CAD designed and CNC manufactured.

I am open and covet any and all input you can give me...after all, it is for your benefit as well as mine.

Looking forward to hearing from all of you Jag guys out there.

Thank you,

Jim

http://www.clubcobra.com/forums/club-cobra-introduction-forum-introduce-yourself/134144-jag-irss.html#post1356717

Keep up the good work. So you did move the resevoirs off the pedal assy?

Ralphy

A magnetic base you can turn on and off.

Ralphy

Is it a multi-link design? If so, you better be pretty talented at replicating all the datum points. It would be fairly involved.

By the way, welcome aboard!

Ralphy

But aluminum does flex as you said, that's my point. And it does not fatigue as much as common thought, if made right. If it can stand the rigors of Moto X's constant pounding and a wing flexing millions of times?

By Tyrell, "Nearly all of the machine work was done on two planes, X and Y. I didnt see any compounded curves anywhere on it. Kind of like the the aluminum work supporting the quick change in the 68 vette. All done on two planes and as simple as CNC milling gets."

Where have you seen a CNC "profile" parts? Maybe custom wheel manufactures? That would require many hours with little value.

Question: What is a defect?
Answer: Anything that adds cost that adds no value!

If the guy spent countless hours massaging a practical part you can't see anyhow. Trying to turn it into a show piece/ Gold Bricking? He would have to way up the price. Eliminating buyers and not selling much of anything. This market is limited anyhow.

Ralphy

tyrellracing wrote:

In the over view I do admit the billet LCA's look sweet. I think they look lonely with out upper control arms of the same quality... LOL

Something to say about 2 coilovers for looks. Wonder if someone makes a superlight dual setup?

Ralphy
 

Cool!
Ralphy
 

Digz, I just saw your post. I agree 800 psi actually sounds pretty high at the rears. Remember this larger pistons at the caliper equal more braking force and more travel at the pedal. A larger piston on the master cylinder equals less force, meaning you'll have to push harder to stop. But less travel. It pushes more fluid decreasing travel but you have to push harder.

Typicall MC's for Cobra guys are 3/4", some even use 5/8".

Guys that track their cars use a porportioning valve like the one below. It's a six position lever so you can fine tune the rears for those really hairy turns and remove locking of the rears. Set up so you can change while driving. As the Wilwood rep said, you want to stop a car with the rears as much as possible. So you limit upsetting the front end. However the fronts do most the work.


The propotion valve adjuster sets where it kicks in. Before this point it flows 100%. Once it reaches it's set point it halves any increases. So say it's set at 500 psi, once you reach 500 if you pdal what would be 600. You'll get 550 psi.

Here's where someone charted the valve The intersect point is where the proportioning valve is set to kick down line pressure. Line pressure increases at 50% from that point.


I know your talking using a booster but all this still applies. As Digz said it's only an assist.

Ralphy

tyrellracing wrote:

Pretty to look at. However it looks to me like they weakened the design by putting the shock bolt through the center of the control arm. Thats the highest stressed area in that type of control arm. The design is all ready weakened by their choice to use aluminum.. The load path begins there and should have been the last place to drill a 1/2 inch hole. To have placed ears above or below the arm would have been superior. Ralphy posted a stock Jag LCA that cracked in half inches from the shock mount. The steel Jag control arms are pretty stout units.  Aluminum fatigues much faster than steel in high stress applications like Jag LCA's.  Pretty to look at, Poor design.Short service life.  

Well if you go to their web site. The design is used for racing applications, however? They also use only 1 coilover at the front. Which would increase the stress. So if your to go with double coilovers for the street?  Half the stress? Aluminums life varies dependent on what type used. One of lifes trade offs! I'm sure if you contacted them they would tell you what material they use and life expectancy.

The OEM Corvette C4 IRS is mostly aluminum! However not the same.

http://www.cobraracing.com/

What would concern me? If someone were to think they could use that LCA and not pin/control the upright above the halfshaft. Myself, I'll stick with steel.



Ralphy

Here is a guy in NY posting here. With a quick change in a retired show car. Using a double wishbone design. All custom built.

http://irsforum.boardhost.com/viewtopic.php?id=574



Ralphy

http://s350.photobucket.com/user/acmjg/media/MOV04917.mp4.html

Watts video.

Have fun, that's a lot of stuff to go thru.

Ralphy

Wow! Now here's a guy who's done some homework! Damn so many good questions. Let's start off with, welcome longhornss. Many of your answers are here. Try using the search feature first off.

Next, should the lca be level? According to many here, yes. Your next question I'm guessing refers to half shaft angle? When the lca is level the HS should be uppward at the wheel. Refrence univesal joints best angle, 3 degrees. Now let me add, Corvette C3 runs their HS's level app. Zero degrees.  And the lca downward out. Pinion, at parallel to trans but 3 degrees univesal angle front and rear matched. Radius rod should be inline to the inner pivot point of the lca.

Ralphy

Okay I checked into it. Use the search feature for UHMW and you will be richly rewarded.

And maybe Day can make a sale!

Ralphy

Field of thousands of classic car dreams for sale

http://www.foxnews.com/leisure/2014/02/28/field-thousands-classic-car-dreams-up-for-sale/

Ralphy