Race Car Tech Discuss anything related to road racing and auto X.

My panhard bar snapped at Lime Rock today!

Thread Tools
 
Search this Thread
 
Old Oct 30, 2004 | 06:21 PM
  #1  
Ben 84 RX-7's Avatar
Thread Starter
Full Member
Tenured Member 05 Years
 
Joined: Oct 2003
Posts: 136
Likes: 0
From: NY
My panhard bar snapped at Lime Rock today!

I started my turn in at Big Bend (turn 1)...and BAM! The panhard bar snapped in two. Off into the dirt I went (without any contact luckily!) Is this a fairly common failure?

Ben
Reply
Old Oct 30, 2004 | 07:07 PM
  #2  
grafddrx7's Avatar
Full Member
Tenured Member 05 Years
 
Joined: May 2003
Posts: 77
Likes: 0
From: Bowling Green, Ohio
Don't know alot about first-gens, I'm just glad to hear you didn't wad your car up and that you're allright!!!

There's a guy around here who runs in ITA, and has a company called G-Force engineering that does some suspension stuff for first-gens, so he might be able to help...

Just found his ad in Sportscar magazine... Sells a "GT Panhard" deal, so maybe this is something worth looking into.

Website is gforceengineering.net...

I believe his name is Jim Cusco, and he's in Findlay, Ohio, about 45 minutes from Toledo, if that helps...

Good luck, and keep it outta the kitty litter!!!
Reply
Old Oct 30, 2004 | 07:15 PM
  #3  
Ben 84 RX-7's Avatar
Thread Starter
Full Member
Tenured Member 05 Years
 
Joined: Oct 2003
Posts: 136
Likes: 0
From: NY
Thanks! I'll check it out!
Reply
Old Oct 31, 2004 | 06:20 AM
  #4  
cpa7man's Avatar
Racing is life!
iTrader: (2)
 
Joined: Jan 2003
Posts: 2,173
Likes: 0
From: Grapevine, TX
Originally Posted by grafddrx7
Don't know alot about first-gens, I'm just glad to hear you didn't wad your car up and that you're allright!!!

There's a guy around here who runs in ITA, and has a company called G-Force engineering that does some suspension stuff for first-gens, so he might be able to help...

Just found his ad in Sportscar magazine... Sells a "GT Panhard" deal, so maybe this is something worth looking into.

Website is gforceengineering.net...

I believe his name is Jim Cusco, and he's in Findlay, Ohio, about 45 minutes from Toledo, if that helps...

Good luck, and keep it outta the kitty litter!!!
Jim Susco, yes very good products. Order his book and he will give you free suspension setup consultation.

I like that "wad your car up". Yea you were lucky. A first gen locked its rear end up and hit the wall at Texas Motor Speedway in qualifying yesterday. Good thing and bad that it was the new soft wall. If we hit it we buy it. Ouch!
Reply
Old Oct 31, 2004 | 04:01 PM
  #5  
grafddrx7's Avatar
Full Member
Tenured Member 05 Years
 
Joined: May 2003
Posts: 77
Likes: 0
From: Bowling Green, Ohio
Luckily, from what I remember about LRP, there's alot of run-off area at turn one, so if this was gonna happen, this was probably the best spot...
Reply
Old Oct 31, 2004 | 07:22 PM
  #6  
speedturn's Avatar
Rotary Enthusiast
Tenured Member 10 Years
iTrader: (1)
 
Joined: Jul 2004
Posts: 1,035
Likes: 2
From: Rocket City, Alabama
I use G-Force Engineering products on my 1979 IMSA GTU vintage racer, for about 5 years now. His stuff is well engineered, and since he is a trained suspension engineer (GM Institute) he really knows RX-7 suspension better than most racers do. Many top production car and IT car racers run his pieces.

http://www.gforceengineering.net/products.htm
Reply
Old Oct 31, 2004 | 07:26 PM
  #7  
Ben 84 RX-7's Avatar
Thread Starter
Full Member
Tenured Member 05 Years
 
Joined: Oct 2003
Posts: 136
Likes: 0
From: NY
What have you guys heard about the ISC panhard setup? Seems to be really similar to the G force one. Yes, Big Bend does have plenty of run off...the only corner at Lime Rock that does! I definitely dodged a bullet on that one!
Reply
Old Oct 31, 2004 | 11:07 PM
  #8  
cpa7man's Avatar
Racing is life!
iTrader: (2)
 
Joined: Jan 2003
Posts: 2,173
Likes: 0
From: Grapevine, TX
Originally Posted by Ben 84 RX-7
What have you guys heard about the ISC panhard setup? Seems to be really similar to the G force one. Yes, Big Bend does have plenty of run off...the only corner at Lime Rock that does! I definitely dodged a bullet on that one!
A lot of good racer use his stuff. ISC is a great place for Mazda racing parts. Mike is very helpful and they have a quick turnaround. I have ordered a few things from them. I think that the advanced shocks with the redesigned front struts and with all of the other gforceengineering stuff would be the hot ticket for first gen handling. Just expensive......how much faster would it be than the ISC setup? I would guess less than a second or two per lap.
Reply
Old Nov 1, 2004 | 07:01 AM
  #9  
Ben 84 RX-7's Avatar
Thread Starter
Full Member
Tenured Member 05 Years
 
Joined: Oct 2003
Posts: 136
Likes: 0
From: NY
Originally Posted by cpa7man
A lot of good racer use his stuff. ISC is a great place for Mazda racing parts. Mike is very helpful and they have a quick turnaround. I have ordered a few things from them. I think that the advanced shocks with the redesigned front struts and with all of the other gforceengineering stuff would be the hot ticket for first gen handling. Just expensive......how much faster would it be than the ISC setup? I would guess less than a second or two per lap.

Did I understand you right...you think the G Force panhard makes that much more difference than the ISC panhard?
Reply
Old Nov 1, 2004 | 07:10 AM
  #10  
cpa7man's Avatar
Racing is life!
iTrader: (2)
 
Joined: Jan 2003
Posts: 2,173
Likes: 0
From: Grapevine, TX
Originally Posted by Ben 84 RX-7
Did I understand you right...you think the G Force panhard makes that much more difference than the ISC panhard?
No, I think both are just about the same. But if I was going to go with the full setup I would go with Gforce. Susko offers a more complete higher end package. Like I said a lot of guys run the ISC stuff and love it. Also look at ground controll stuff.
Reply
Old Nov 1, 2004 | 07:47 AM
  #11  
Ben 84 RX-7's Avatar
Thread Starter
Full Member
Tenured Member 05 Years
 
Joined: Oct 2003
Posts: 136
Likes: 0
From: NY
Gotcha...Thanks for the input!
Reply
Old Nov 1, 2004 | 08:29 AM
  #12  
speedturn's Avatar
Rotary Enthusiast
Tenured Member 10 Years
iTrader: (1)
 
Joined: Jul 2004
Posts: 1,035
Likes: 2
From: Rocket City, Alabama
Exactly which part snapped on your old panhard rod?
What brand was your old panhard rod?

Inquiring minds want to know
Reply
Old Nov 1, 2004 | 08:35 AM
  #13  
Re-Speed.com's Avatar
Banned. I got OWNED!!!
iTrader: (3)
 
Joined: Nov 2001
Posts: 2,483
Likes: 1
From: London, Ontario
Yes, Give us the details.

-billy
Reply
Old Nov 1, 2004 | 10:39 AM
  #14  
Ben 84 RX-7's Avatar
Thread Starter
Full Member
Tenured Member 05 Years
 
Joined: Oct 2003
Posts: 136
Likes: 0
From: NY
My father has a ground control panhard bar on his car that I took to a fabrication shop and had them make one like it...apparantly the shop isn't that good! It only had 4 races on it. The bar makes a bend and goes under the rear end. There is a brace welded onto it at the bend. It snapped right after the brace ends. I guess you get what you pay for!
Reply
Old Nov 1, 2004 | 10:48 AM
  #15  
DriveFast7's Avatar
Blood, Sweat and Rotors
Tenured Member 20 Years
iTrader: (1)
 
Joined: Aug 2001
Posts: 3,742
Likes: 1
From: California
Ouch! I have the Ground Control panhard and it came with a gussett on the bend, facing front of car. We welded a larger, wider gusset same spot, on the bend, but facing rear of car. Have 10 weekends of hot lapping on that car including some with slicks. Hasn't had a problem.
Reply
Old Nov 1, 2004 | 11:38 AM
  #16  
cpa7man's Avatar
Racing is life!
iTrader: (2)
 
Joined: Jan 2003
Posts: 2,173
Likes: 0
From: Grapevine, TX
FWIW - The ep first gen I just bought has Ground Control pan hard and 3rd link on it. This class runs slicks and the Ground Control parts have been on this car for at least a dozen races. Very durable to chime in on what Brad said. I'm going to keep what I have and add GForce's turn in spacers and other pieces as the budget permits.
Reply
Old Nov 1, 2004 | 12:26 PM
  #17  
Ben 84 RX-7's Avatar
Thread Starter
Full Member
Tenured Member 05 Years
 
Joined: Oct 2003
Posts: 136
Likes: 0
From: NY
Originally Posted by cpa7man
FWIW - The ep first gen I just bought has Ground Control pan hard and 3rd link on it. This class runs slicks and the Ground Control parts have been on this car for at least a dozen races. Very durable to chime in on what Brad said. I'm going to keep what I have and add GForce's turn in spacers and other pieces as the budget permits.

Absolutely...keep in mind guys, my bar was NOT a Ground Control bar! It was a Ground Control REPRO that I had a shop make. Stupidly, I didn't ask the guy at the shop what thickness he used for tubing etc. I couldn't find a Ground Control bar since they stopped making them, so I had one made. I will never do that again!

If I had an actual Ground Control bar, I would use it in a hearbeat.
Reply
Old Nov 1, 2004 | 10:50 PM
  #18  
'85 GSL 302's Avatar
Senior Member
Tenured Member 05 Years
 
Joined: Apr 2003
Posts: 479
Likes: 0
From: SC
It's rare, but it's been known to happen. I was doing F&C for a NASA race and an IT7 had the same thing happen. He finished the last 3 laps of the race dragging the bar. I think they "meat balled" him one the second lap but he finished anyway.

I don't think it's an issue of the parts being faulty. I think it's more allong the lines of once you start modifing things, you're eventually going to have something break. I wouldn't worry about it in the future, but I'd certainly pay attention to the part that failed and make it stronger next time.

Rob
Reply
Old Nov 2, 2004 | 08:17 AM
  #19  
Re-Speed.com's Avatar
Banned. I got OWNED!!!
iTrader: (3)
 
Joined: Nov 2001
Posts: 2,483
Likes: 1
From: London, Ontario
Originally Posted by '85 GSL 302
I don't think it's an issue of the parts being faulty. I think it's more allong the lines of once you start modifing things, you're eventually going to have something break. I wouldn't worry about it in the future, but I'd certainly pay attention to the part that failed and make it stronger next time.
I would second that. Race car parts break! If you had it made out of 4 inch diameter steel rod it would not have broken, but it would weigh a ton. designing race car parts is always a compromise. No reason to give up on it.

You say it broke at the point where the gusset stopped. That will be a weak spot on the part for two reasons. 1) The welding at that point would have made the part brittle. 2) The part is ridged until the point where the gusset stops then it is just bar again. So there would be allot of stress on the part at that point.

Since the part is toast at this point this is what I would do. 1) Measure the wall thickness of the material. 2) Call and ask the shop what material they made it from. Ask if it was a welded seam tube or a DOM. If it is mild steel or 4100 series material, and if it was tig or mig welded.

Take the above information and make an assessment as to what went wrong. Adjust for your assessment and remake the part.

If you would like, Bring the information back here and I can help you. - Or - Send the part to me and I will make you one.

-billy
Reply
Old Nov 2, 2004 | 08:40 AM
  #20  
Full Member
Tenured Member 10 Years
iTrader: (1)
 
Joined: May 2003
Posts: 198
Likes: 0
From: St. Simons, GA
Just a quick thought, but I have never seen a GC panhard. We run a G-Force panhard that to the best of my knowledge, goes behind the axle pumpkin, not under. This provides for a straight panhard rod, which is a lot stronger than a bent rod. Good for two reasons, more ground clearance, and able to adjust the panhard height to adjust rear roll center. I know that GC makes great stuff, we run a front setup from them, but think that going under the axle is not the best setup. Maybe there is another reason for this, as I realize that Jay and the folks at GC are very knowledgeable. just another .02.

Travis
Reply
Old Nov 2, 2004 | 09:33 AM
  #21  
DamonB's Avatar
Lives on the Forum
Tenured Member 15 Years
 
Joined: Feb 2001
Posts: 9,617
Likes: 8
From: Dallas
Originally Posted by '85 GSL 302
I don't think it's an issue of the parts being faulty. I think it's more allong the lines of once you start modifing things, you're eventually going to have something break.
I disagree with that. Sure racing stressing things immensely, but the part should be designed to fill the job. A part failure isn't a failure of the part itself, it usually lies somewhere else. It could be the failure of the engineer who designed it. When it was designed properly and fails its the fault of the guy who welded it up. When it was designed and welded up properly and fails it's the fault of a bad batch of material. When it was designed and welded up properly, the material was good and the part still fails it's the fault of the user not inspecting the part. It's VERY rare for something to instantly and catastrophically fail. The part will always exhibit some sort of failure mode before hand but you have to make the effort to look.

Inspection is one of the most important things in racing and it's the one that is most often overlooked.
Reply
Old Nov 2, 2004 | 09:40 AM
  #22  
Rx7carl's Avatar
Airflow is my life
Tenured Member 10 Years
 
Joined: Aug 2002
Posts: 6,736
Likes: 2
From: Orlando, Fl
I run a g-force panhard and have gotten close up with the ISC piece. I love the gforce one, very well engineered. The ISC piece is comparable, but a bit overbuilt IMO. More like the way a guy like me would build it, not being an engineer. Mikes a good and helpful guy, so is Jim SUSKO. I've seen pics of the GC bar and Im not impressed.


Here here Damon! I inspect the car after every session.
Reply
Old Nov 3, 2004 | 01:27 PM
  #23  
Speed Raycer's Avatar
Senior Member
Tenured Member 05 Years
 
Joined: Jan 2002
Posts: 350
Likes: 0
From: Missouri
I'm running a G-Force bar on mine. The only problems I've had with it was the brace bar bending and the body mount weld breaking. The brace wasn't the original bar supplied by Susco and the body mount seems a little bit under engineered, but it works fine.

I've got some pics of an ISC bar I installed on a customers car.

www.izzyscustomcages.com/projects.html


Last edited by Speed Raycer; Nov 3, 2004 at 01:30 PM.
Reply
Old Nov 3, 2004 | 07:30 PM
  #24  
Ben 84 RX-7's Avatar
Thread Starter
Full Member
Tenured Member 05 Years
 
Joined: Oct 2003
Posts: 136
Likes: 0
From: NY
Thanks for the links! Scott, I wish your shop wasn't so far from NY!
Reply
Old Nov 4, 2004 | 08:03 AM
  #25  
Rx7carl's Avatar
Airflow is my life
Tenured Member 10 Years
 
Joined: Aug 2002
Posts: 6,736
Likes: 2
From: Orlando, Fl
I really want one of his cages in my car. I still may bite the bullet and do it.
Reply



All times are GMT -5. The time now is 12:15 PM.