Scotts build thread

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

Amen Brother! Tell it all!
I have one of those in my past. Regreted it. And still paying for it.
Damn GTs. Thanks to Fran, we can now have a GTR.

Thank you Fran.
Mike
 
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)

ASM Material Data Sheet

Thanks for the input Howard. Yes, I looked at the comparable strengths to steel, and 7075 was the closest. I have seen alot of testing done in compressive and tension with various weights, and seeing as there is a spring to "cushion" the movement, I have seen stresses come in at only 150-175% of its static loads. So if there is 900# on each pushrod in static, then it should only see roughly 1400# or so in compression. That was my calculation in choosing the material. Also read that the 7075 has a fatigue rate very close to steel.
Now, as Fran mentioned, the higher spring rates can raise this compression "shock" hitting rumble strips and potholes. Now if the shock bottoms out, that compressive load can seriously spike. 200-400% of static load. While failure is never good, I lastly thought that most likely a failure would turn into a bend, not a break. Still not good, but it would not be nearly as uncontrollable as say loosing a wheel and more comparable to getting a flat.

So, all of that was what I based my decision on. Is it right? Who knows, Hahaa. I did see that you made new upper control arms, which is really my next step if I ultimately do not feel comfortable running the hex pushrods in the end and go back to steel. My reason for doing it was to gain a touch more clearance off of the control arm to get more droop out of the rear as I was only getting 1.75" from ride height, which is fine for racing, but i would be pulling tires up in lots of places including my driveway approach.

So it was more about that than making a flashy part. the hex bairily gave me any more droop even with it being slightly thinner (when spun to the correct angle) so I am still looking for options before clearancing the control arm itself. Any ideas anyone?

I also had the old style bellcranks that were causing abit of ruckus too. Ordered the new style from Fran and now atleast the coilover body does not bind. Ultimately though, I need to make it so I have full suspension travel based on the travel of the shock. Won't be able to sleep at night unless I do. Hahaha.
 
And since i havn't gotten crap done on it in about 4 days, here is another pic of that great Ford GT!

th
 

Fran Hall RCR

GT40s Sponsor
Scott
As a point of reference , and you know this already.
Your car is not a production car and as such it has quite a few differences over a production build

Your bell cranks are in a different location and also a different angle than production too
 
I'm thinking there will be a lot of droop in the back end of that GT in about twenty years from now, but right now it looks damn good :p
wonder if there's enough room for her and her two friends in that there car ?
 
No apologizes needed, I am pretty sure I started it with the pic, then the second pic. Hahaha. I am also sure, there will be more of them too!
 
Trying to load up on parts. Since my action has been lacking lately, I have scheduled about 3 weeks off work, and me and one of the guys working for me will hopefully belt it out pretty quick. 40hrx2 x3= 240hrs
Finally have a game plan down on body mods. Hard to explain in text, but Enzo style headlight design, center divider on rear to hang wing from, resculpted sides, and more behind the rear tire. The theme will be "gills".
The first cut is always the hardest. :laugh:
 
:thumbsup: I can't wait to follow the progress on this. It sounds like some very nice modifications are in store.
 
Thanks Troy. Oregon has been in some level of hell heat wave where 90-100 degrees has been the norm lately and my garage faces the afternoon sun. I think we have already topped the highest temp from last year in August. Oregonians aren't built for this and i hope it ends soon so I can get back to work. Getting close to spending the money on garage a/c. Atleast fg will set up super fast and once we take time off, we can get going early before the heat.

What are some of you guys doing in the form of garage cooling in AZ or CA or TX?
 

Scott

Lifetime Supporter
You should check out the Mitsubishi mini splits. I just installed one in my garage. They are ductless and very efficient. In addition to AC, they have a dehumidification feature (“dry mode”) that provides added moisture control without lowering the temperature of the room. In this mode the fan speed slows slightly so that the air can spend more time on the indoor coil therefore wringing out more moisture. Given my investment in tools and cars, this seemed like a great feature. If you add a heat pump, you can also get heat.
 
Thanks Scott. Those do look like a good option. I did call my hvac guy this afternoon and he is willing to do the whole house for a smoking deal, with garage registers too. Wonder what he could do cost wise on one of the mitsu units? It is 10pm here now and it is 89 inside of the house, garage the same! Normally don't need it here as we only get about a week in the 90's all summer. I am disliking, now we are into our second week of 90's. Supposed to be knocking on 100 for the next 10 days. ugh.
 
Temps have finally cooled off abit here to normal and a little time off work, so back to it. Spent a couple hours on the fuel system.
A holley black feeder pump, to the swirl pot, to a Holley 12-1200 pump, to the largest fuel filter (100 micron) I have ever seen! There is also a 30 micron sock type insert in the fuel cell. Should get the job done. Surprised it fit with relatively easy bends of the hoses. I will also be installing a check ball/roll over vent to the tank. Will get to it once I cut in the sending unit.



 
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