Two Shakes the S10

[Rex Schimmer]

My son and racing partner, Duke, works at Chuckle's Garage here i n Santa Rosa and they have been building a new small pickup for Bonneville. He designed and fabricated the cage. I have attached a pic that may give you some ideas on your cage.

Rex

[fissionspeed]

My son and racing partner, Duke, works at Chuckle's Garage here i n Santa Rosa and they have been building a new small pickup for Bonneville. He designed and fabricated the cage. I have attached a pic that may give you some ideas on your cage.

Rex

I saw the truck revealed on Instagram, quite a machine. 1/4 million dollars. Glad I'm not running F class.

[Rex Schimmer]

You are right that it is pretty impressive and the owner Scott is a great guy but I personally prefer projects like yours. Pretty much a one man deal and you have to watch the dollars. Lots of satisfaction when you do most of the work yourself. Keep it up and keep us posted.

Rex

[fissionspeed]

Some minor updates:

- Those no-name china fuel rails ended up biting me. The injector bores were way out of spec and I pushed an o-ring out, spraying fuel everywhere. Glad that didn't happen under power. Tried a few different styles and had to return them all, it appears no matter who sells cheap fuel rails, they all come from the same factory. Ended up getting some holley rails which had the correct bore size.
- Torque converter and transmission are mated and ready to be bolted to the engine. I have my SFI blanket ready to install before it all goes in
- Motor mounts installed. The trans crossmember I got secondhand appears to be a factory error with the mount on upside down, so that will have to be modified

Major updates:

- finally finished narrowing the ford 8.8 and adding the ford 9" ends required for axle retention. I have a couple Quick performance axles, girdle cover, and drum brake kit on the way
- I got a TIG machine and was able to make my chromoly 4-link bars. With this done and the housing narrowed, I was able to put everything under the car and check my work on the whole rear suspension. Still need to add the diagonal link, but miraculously it appears I was able to keep everything relatively square. I'm pretty proud of that considering I didn't know how to weld when I started, and here in california the lines on the floor have a habit of moving 

Next steps:

- get shocks and springs (we'll have a roller at this point!)
- figure out how I want to cut the floor pan to get the engine and trans in the car
- get the engine and trans in the car
- add frame crossbrace and driveshaft safety loop
- get the roll cage in the car (currently sweating this. I'm pretty okay at welding on the bench but twisted up like a pretzel is yet to be seen)
- (everything else on the car)

I am beginning to see the light at the end of the tunnel. Need to hit it hard, only 127 days until el mirage tech inspection!

[Gary Freudenberger]

Spend a couple days drinking with your buds looking at the options

Sound approach, Stainless

[Stainless1]

Spend a couple days drinking with your buds looking at the options

Sound approach, Stainless

Gary, It usually works for me... beergineering at its best... the solutions will come....   

[fissionspeed]

Since this project started the technique has been employed several times to great effect!

Gary, It usually works for me... beergineering at its best... the solutions will come....   

[fissionspeed]

Update: We're in. RIP oil filter who bravely sacrificed his life in this process. The oil pan is a tight squeeze but it looks like we're good on steering clearance. The engine sits nice and high which will be good for the lowered stance but I reckon some of the floor is going to have to go. Once I get the frame leveled back out (some migration occurred during the persuasion of the drivetrain) I can get the cage started. I'm hoping to have that all tacked in this week. 88 days to go and a hell of a lot left to do.

[fissionspeed]

Seat installed, driveshaft tunnel installed. Ended up not having to do a trans tunnel, instead I lowered the engine 1 inch by modifying the motor mounts. So far it looks like everything is lining up well, but I will need a 2pc shaft due to how long the car is. Also restored an old racing wheel with some 3D printed parts while procrastinating on starting the cage.

[Gary Perkinson]

Hey...haven't checked in in over a year...great job! I hope you can pull all the little (and some big) crap together before August...keep us posted!  :clap

[Rex Schimmer]

I am not a fan of a two piece drive shaft, just double the number of potential problems. Why not go with a larger diameter shaft? I would think that a 4 inch dia shaft would work. The loads a drive shaft see are both torque and also the sine wave torque fluctuation that is a product of the U joint angle. If you can get the angle of the shaft fairly straight then the amplitude of the torque fluctuation is lower.

Rex

[Interested Observer]

While some driveshaft failures may be due to over-torquing, most high speed failures are due to uncontrolled resonant bending of the tubing, leading to buckling, generally at the midpoint.  This is unrelated to u-joint angularity but can be aggravated by that. 
Shorter unsupported lengths and increased bending stiffness (large diameter) raise the natural bending frequency of the tube and permit higher speeds.  The mass of the tube also enters into it?aluminum, composite? 

[Rex Schimmer]

This is a handy chart regarding critical speeds of shafts that differ in diameter, material, lengths and speeds. Note the composite shaft has the highest frequency due to the inherent high stiffness of carbon fiber. This chart is based upon the natural frequency in torsion of the shaft, which is dependent upon the "E" value of the material , the diameter of the shaft, the wall thickness if using tubing and the square root of the cube root of the length (?) Which explains why the frequency is not linear to the length.

Rex

[fissionspeed]

By my math I need to run about 7500 RPM to hit my goals at elmo (205) and bonneville (225) with a 3.08 and 2.73 gear respectively. Since I don't want to hang out at the critical speed RPM, I went with 20% factor of safety, so we'll say I need it to be capable of 9300 RPM. With a 68 inch length between my output yoke and my pinion, that diameter starts to get very close to my right leg. I figured it would just be simpler to eliminate the problem. The crossmember for the carrier bearing is already there anyway.

[Rex Schimmer]

Sounds like good logic, especially since the crossmember is already there. I like your thinking of going with a 20% cushion. Better safe than sorry.

Rex