Scotts build thread

Finally today the phone stopped ringing and was able to get a couple hours in on car.
Parking brake lines finally mounted and cables inside car. My cables were not long enough so I had some other s.s. cable in the garage and tig welded some length on to them. After the weld I put heat shrink on the cables themselves to eliminate any chaffing to shifter cables and/or alum gas tank. Now, time to decide on handle location and then I gots some stops!





riv-nuts into alum and fastened bracket. Should be very solid. Shifter cables are tight as a guitar string right now, so will be remounting shifter. Looking at the later model chassis, I will be redoing some of the bars inside of the cockpit to make better mounting position for shifter and more room for center console and dash layout.

 
Jumped back into doing wiring today (yup, I jump around, what ever part is closest to me I grab, lol). Mostly just testing wire lengths and drilling some holes. Got battery cable going to front and hole cut for front harness and fastened in.
No pics today, but to keep it interesting, I will put this up for viewing pleasure! Yes, a picture of a GT Ford.

 
New rear pushrod, toe adjuster made. Still need to taper ends. L and R threaded. 7075 alum used, can now be polished, or anodized.

 
Quick hand polish on the new bars. Installed pic.



The wiring is going...............great. Shit everywhere.


Pics of simple remounting of tilt motor to not hit your toe on or hang too low.


 
So much for worrying about ME breaking the windshield, found this after removing the strategicly placed vinyl banner at top of windshield. Ugh.


 
I guess it took the pressure off of me breaking it myself, and put that pressure right back onto my wallet! Atleast it will be months before needing the new one.
 
You might be surprised, this varies state to state. Texas inspects the tint on a windshield and the condition of the wiper but not the windshield itself. The material or if it has cracks doesnt matter. If you are in NY or MA, your screwed. OR might let you slide
 
You might be surprised, this varies state to state. Texas inspects the tint on a windshield and the condition of the wiper but not the windshield itself. The material or if it has cracks doesnt matter. If you are in NY or MA, your screwed. OR might let you slide

I'm hedging my bets and trying to get my lexan one passed here soon for MN.

The way I look at it... if it's good enough for racing, hell it's just fine for the tame streets.
 

Howard Jones

Supporter
I have included a couple of links. Of note is the tensile strength values. 4041 CM steel is significantly stronger than 7075 T6 aluminum. 95Kish to about 83Kpsi. Shear modulus number differences between steel and aluminum are huge. 3900Ksi to about 11000Kis. Additionally I believe that CM tubing is structurally much more resistance to bending than hex solid alum shaft. It appears to me that you have reduced the strength of that push rod significantly maybe a LOT more, as it fatigues.

Watch the female shaft rod end thread wall very carefully for cracking and elongation. If it fails it will be at one end or the other. Most likely in one of the rod end to shaft interfaces. That's where all the stress risers are.

The push rod on the rear suspension is just about the most highly loaded suspension part on the car with the possible exception of the rear hub shafts.

I love all my SLC and GT40 friends and I would urge you to consider the consequences of experimenting with suspension parts. I am not a mechanical engineer but I have learned a few things mostly from trial and error. We all like to put our personal touches on our cars but sometimes it may not the best idea we ever had to mess with the "itwillkillyaparts" as I like to call them. The term comes from a certain set of handlebars that I "fixed" between moto's a very long time ago. My neck still hurts from that lesson.

Anyway here's the info.

AISI 4140 Alloy Steel (UNS G41400)

http://asm.matweb.com/search/SpecificMaterial.asp?bassnum=MA7075T6
 
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Howard Jones

Supporter
Scott I hope that you don't think I'm some kind of know it all internet board as# Ho#$. The alum piece will be OK, IF, and that's the real deal here, IF the Push rod ONLY is loaded in tension.

7075 and steel are near the same "strength" in tension. BUT if the rod is subjected to much, and I mean ANY lateral forces meaning shear forces, then they will reduce its combined resistance to failure by a lot very quickly.

It would take quite a bit of analysis and/or testing to determine if that rod is only loaded up and down. I suspect it will be loaded a bit in both X and Y directions. And that is the gamble.

I have had my stuff "reviewed" many times on this website. Some times publicly and other times via PM's. Thank god! and all my friends here. I think it serves us all well to air our inspirations publicly. Sort of a home builder pear review. That's the real value of GT40s.com.

Thanks again Ron!
 
Yeah Howard I like the way you think. I need to Peer at this Build for a while.

I know there is a fault there somewhere.

 
Don, if you find a fault in this inspired build, I believe you would have to be under the influence of unnatural things... :)

Mike
 

Fran Hall RCR

Moderator
GT40s Sponsor
I would feel well shaded if I was under those unnatural things...

I did mention my concern to Scott when he told me about the aluminum hex .

On the race cars we double wall the steel pushrods as they see serious loading with 1000-1300lb springs
 

Dr. David

Lifetime Supporter
The Ford GT has great performance, and the maintenance expenses are very reasonable....and it only costs you about $250K......seems lika a good investment.

The other unit has a performance index that can be highly variable and unpredictable......and the maintenance can be astronomical....Further, unless you have an iron-clad lease agreement, it can cost you half of everything that you own....and a big chunk of everything you will make for the rest of your life!

Just like the Concours d'Elegance: Look but don't touch!

Just my opinion,
David
 
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